diff --git a/boot.php b/boot.php
index ebdb58236..9b18361b0 100644
--- a/boot.php
+++ b/boot.php
@@ -179,63 +179,32 @@ define('CP_USERS_AND_GLOBAL',       2);
  * @}
  */
 
-/**
- * @name Network constants
- * @deprecated since version 3.6
- * @see Protocol
- *
- * Network and protocol family types
- * @{
- */
-define('NETWORK_DFRN'     , Protocol::DFRN);      // Friendica, Mistpark, other DFRN implementations
-define('NETWORK_ZOT'      , Protocol::ZOT);       // Zot! - Currently unsupported
-define('NETWORK_OSTATUS'  , Protocol::OSTATUS);   // GNU-social, Pleroma, Mastodon, other OStatus implementations
-define('NETWORK_FEED'     , Protocol::FEED);      // RSS/Atom feeds with no known "post/notify" protocol
-define('NETWORK_DIASPORA' , Protocol::DIASPORA);  // Diaspora
-define('NETWORK_MAIL'     , Protocol::MAIL);      // IMAP/POP
-define('NETWORK_FACEBOOK' , Protocol::FACEBOOK);  // Facebook API
-define('NETWORK_LINKEDIN' , Protocol::LINKEDIN);  // LinkedIn
-define('NETWORK_XMPP'     , Protocol::XMPP);      // XMPP - Currently unsupported
-define('NETWORK_MYSPACE'  , Protocol::MYSPACE);   // MySpace - Currently unsupported
-define('NETWORK_GPLUS'    , Protocol::GPLUS);     // Google+
-define('NETWORK_PUMPIO'   , Protocol::PUMPIO);    // pump.io
-define('NETWORK_TWITTER'  , Protocol::TWITTER);   // Twitter
-define('NETWORK_DIASPORA2', Protocol::DIASPORA2); // Diaspora connector
-define('NETWORK_STATUSNET', Protocol::STATUSNET); // Statusnet connector
-define('NETWORK_NEWS'     , Protocol::NEWS);      // Network News Transfer Protocol - Currently unsupported
-define('NETWORK_ICALENDAR', Protocol::ICALENDAR); // iCalendar - Currently unsupported
-define('NETWORK_PNUT'     , Protocol::PNUT);      // pnut.io - Currently unsupported
-define('NETWORK_PHANTOM'  , Protocol::PHANTOM);   // Place holder
-/**
- * @}
- */
-
 /**
  * These numbers are used in stored permissions
  * and existing allocations MUST NEVER BE CHANGED
  * OR RE-ASSIGNED! You may only add to them.
  */
 $netgroup_ids = [
-	NETWORK_DFRN     => (-1),
-	NETWORK_ZOT      => (-2),
-	NETWORK_OSTATUS  => (-3),
-	NETWORK_FEED     => (-4),
-	NETWORK_DIASPORA => (-5),
-	NETWORK_MAIL     => (-6),
-	NETWORK_FACEBOOK => (-8),
-	NETWORK_LINKEDIN => (-9),
-	NETWORK_XMPP     => (-10),
-	NETWORK_MYSPACE  => (-11),
-	NETWORK_GPLUS    => (-12),
-	NETWORK_PUMPIO   => (-13),
-	NETWORK_TWITTER  => (-14),
-	NETWORK_DIASPORA2 => (-15),
-	NETWORK_STATUSNET => (-16),
-	NETWORK_NEWS      => (-18),
-	NETWORK_ICALENDAR => (-19),
-	NETWORK_PNUT      => (-20),
+	Protocol::DFRN     => (-1),
+	Protocol::ZOT      => (-2),
+	Protocol::OSTATUS  => (-3),
+	Protocol::FEED     => (-4),
+	Protocol::DIASPORA => (-5),
+	Protocol::MAIL     => (-6),
+	Protocol::FACEBOOK => (-8),
+	Protocol::LINKEDIN => (-9),
+	Protocol::XMPP     => (-10),
+	Protocol::MYSPACE  => (-11),
+	Protocol::GPLUS    => (-12),
+	Protocol::PUMPIO   => (-13),
+	Protocol::TWITTER  => (-14),
+	Protocol::DIASPORA2 => (-15),
+	Protocol::STATUSNET => (-16),
+	Protocol::NEWS      => (-18),
+	Protocol::ICALENDAR => (-19),
+	Protocol::PNUT      => (-20),
 
-	NETWORK_PHANTOM  => (-127),
+	Protocol::PHANTOM  => (-127),
 ];
 
 /**
diff --git a/include/api.php b/include/api.php
index 4fbbc3777..9fe3cb4bd 100644
--- a/include/api.php
+++ b/include/api.php
@@ -692,7 +692,7 @@ function api_get_user(App $a, $contact_id = null)
 
 	if ($uinfo[0]['self']) {
 		if ($uinfo[0]['network'] == "") {
-			$uinfo[0]['network'] = NETWORK_DFRN;
+			$uinfo[0]['network'] = Protocol::DFRN;
 		}
 
 		$usr = DBA::selectFirst('user', ['default-location'], ['uid' => api_user()]);
@@ -4702,7 +4702,7 @@ function api_friendica_remoteauth()
 
 	$contact = DBA::selectFirst('contact', [], ['uid' => api_user(), 'nurl' => $c_url]);
 
-	if (!DBA::isResult($contact) || ($contact['network'] !== NETWORK_DFRN)) {
+	if (!DBA::isResult($contact) || ($contact['network'] !== Protocol::DFRN)) {
 		throw new BadRequestException("Unknown contact");
 	}
 
diff --git a/include/conversation.php b/include/conversation.php
index 6aaf67a6e..3ceccf36a 100644
--- a/include/conversation.php
+++ b/include/conversation.php
@@ -11,6 +11,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -542,7 +543,7 @@ function conversation(App $a, array $items, $mode, $update, $preview = false, $o
 		if ($mode === 'community') {
 			$writable = true;
 		} else {
-			$writable = ($items[0]['uid'] == 0) && in_array($items[0]['network'], [NETWORK_OSTATUS, NETWORK_DIASPORA, NETWORK_DFRN]);
+			$writable = ($items[0]['uid'] == 0) && in_array($items[0]['network'], [Protocol::OSTATUS, Protocol::DIASPORA, Protocol::DFRN]);
 		}
 
 		if (!local_user()) {
@@ -575,7 +576,7 @@ function conversation(App $a, array $items, $mode, $update, $preview = false, $o
 				$sparkle     = '';
 
 				// prevent private email from leaking.
-				if ($item['network'] === NETWORK_MAIL && local_user() != $item['uid']) {
+				if ($item['network'] === Protocol::MAIL && local_user() != $item['uid']) {
 					continue;
 				}
 
@@ -713,7 +714,7 @@ function conversation(App $a, array $items, $mode, $update, $preview = false, $o
 				builtin_activity_puller($item, $conv_responses);
 
 				// Only add what is visible
-				if ($item['network'] === NETWORK_MAIL && local_user() != $item['uid']) {
+				if ($item['network'] === Protocol::MAIL && local_user() != $item['uid']) {
 					continue;
 				}
 
@@ -793,7 +794,7 @@ function conversation_add_children(array $parents, $block_authors, $order, $uid)
 
 	foreach ($items as $index => $item) {
 		if ($item['uid'] == 0) {
-			$items[$index]['writable'] = in_array($item['network'], [NETWORK_OSTATUS, NETWORK_DIASPORA, NETWORK_DFRN]);
+			$items[$index]['writable'] = in_array($item['network'], [Protocol::OSTATUS, Protocol::DIASPORA, Protocol::DFRN]);
 		}
 	}
 
@@ -842,7 +843,7 @@ function item_photo_menu($item) {
 		$contact_url = 'contacts/' . $cid;
 		$posts_link = 'contacts/' . $cid . '/posts';
 
-		if (in_array($network, [NETWORK_DFRN, NETWORK_DIASPORA])) {
+		if (in_array($network, [Protocol::DFRN, Protocol::DIASPORA])) {
 			$pm_url = 'message/new/' . $cid;
 		}
 	}
@@ -858,12 +859,12 @@ function item_photo_menu($item) {
 			L10n::t('Send PM') => $pm_url
 		];
 
-		if ($network == NETWORK_DFRN) {
+		if ($network == Protocol::DFRN) {
 			$menu[L10n::t("Poke")] = $poke_link;
 		}
 
 		if ((($cid == 0) || ($rel == Contact::FOLLOWER)) &&
-			in_array($item['network'], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_DIASPORA])) {
+			in_array($item['network'], [Protocol::DFRN, Protocol::OSTATUS, Protocol::DIASPORA])) {
 			$menu[L10n::t('Connect/Follow')] = 'follow?url=' . urlencode($item['author-link']);
 		}
 	} else {
diff --git a/include/items.php b/include/items.php
index 34d6132f0..7045a2953 100644
--- a/include/items.php
+++ b/include/items.php
@@ -9,6 +9,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Item;
@@ -240,7 +241,7 @@ function add_page_info_to_body($body, $texturl = false, $no_photos = false)
  */
 function consume_feed($xml, array $importer, array $contact, &$hub, $datedir = 0, $pass = 0)
 {
-	if ($contact['network'] === NETWORK_OSTATUS) {
+	if ($contact['network'] === Protocol::OSTATUS) {
 		if ($pass < 2) {
 			// Test - remove before flight
 			//$tempfile = tempnam(get_temppath(), "ostatus2");
@@ -252,7 +253,7 @@ function consume_feed($xml, array $importer, array $contact, &$hub, $datedir = 0
 		return;
 	}
 
-	if ($contact['network'] === NETWORK_FEED) {
+	if ($contact['network'] === Protocol::FEED) {
 		if ($pass < 2) {
 			logger("Consume feeds", LOGGER_DEBUG);
 			Feed::import($xml, $importer, $contact, $hub);
@@ -261,7 +262,7 @@ function consume_feed($xml, array $importer, array $contact, &$hub, $datedir = 0
 		return;
 	}
 
-	if ($contact['network'] === NETWORK_DFRN) {
+	if ($contact['network'] === Protocol::DFRN) {
 		logger("Consume DFRN messages", LOGGER_DEBUG);
 
 		$r = q("SELECT `contact`.*, `contact`.`uid` AS `importer_uid`,
@@ -301,7 +302,7 @@ function subscribe_to_hub($url, array $importer, array $contact, $hubmode = 'sub
 	 * through the direct Diaspora protocol. If we try and use
 	 * the feed, we'll get duplicates. So don't.
 	 */
-	if ((!DBA::isResult($r)) || $contact['network'] === NETWORK_DIASPORA) {
+	if ((!DBA::isResult($r)) || $contact['network'] === Protocol::DIASPORA) {
 		return;
 	}
 
diff --git a/include/text.php b/include/text.php
index 7c8632643..a9a11f76f 100644
--- a/include/text.php
+++ b/include/text.php
@@ -12,6 +12,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -755,9 +756,9 @@ function contact_block() {
 				AND NOT `pending` AND NOT `hidden` AND NOT `archive`
 				AND `network` IN ('%s', '%s', '%s')",
 			intval($a->profile['uid']),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_OSTATUS),
-			DBA::escape(NETWORK_DIASPORA)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::OSTATUS),
+			DBA::escape(Protocol::DIASPORA)
 	);
 	if (DBA::isResult($r)) {
 		$total = intval($r[0]['total']);
@@ -773,9 +774,9 @@ function contact_block() {
 					AND `network` IN ('%s', '%s', '%s')
 				ORDER BY RAND() LIMIT %d",
 				intval($a->profile['uid']),
-				DBA::escape(NETWORK_DFRN),
-				DBA::escape(NETWORK_OSTATUS),
-				DBA::escape(NETWORK_DIASPORA),
+				DBA::escape(Protocol::DFRN),
+				DBA::escape(Protocol::OSTATUS),
+				DBA::escape(Protocol::DIASPORA),
 				intval($shown)
 		);
 		if (DBA::isResult($r)) {
@@ -1039,7 +1040,7 @@ function redir_private_images($a, &$item)
 				continue;
 			}
 
-			if ((local_user() == $item['uid']) && ($item['private'] == 1) && ($item['contact-id'] != $a->contact['id']) && ($item['network'] == NETWORK_DFRN)) {
+			if ((local_user() == $item['uid']) && ($item['private'] == 1) && ($item['contact-id'] != $a->contact['id']) && ($item['network'] == Protocol::DFRN)) {
 				$img_url = 'redir?f=1&quiet=1&url=' . urlencode($mtch[1]) . '&conurl=' . urlencode($item['author-link']);
 				$item['body'] = str_replace($mtch[0], '[img]' . $img_url . '[/img]', $item['body']);
 			}
diff --git a/mod/acl.php b/mod/acl.php
index 29e53394b..f9589598d 100644
--- a/mod/acl.php
+++ b/mod/acl.php
@@ -6,6 +6,7 @@ use Friendica\App;
 use Friendica\Content\Widget;
 use Friendica\Core\ACL;
 use Friendica\Core\Addon;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Item;
@@ -84,8 +85,8 @@ function acl_content(App $a)
 				AND `success_update` >= `failure_update`
 				AND `network` IN ('%s', '%s') $sql_extra2",
 			intval(local_user()),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA)
 		);
 		$contact_count = (int) $r[0]['c'];
 	} elseif ($type == 'a') {
@@ -143,8 +144,8 @@ function acl_content(App $a)
 				$sql_extra2
 				ORDER BY `name` ASC ",
 			intval(local_user()),
-			DBA::escape(NETWORK_OSTATUS),
-			DBA::escape(NETWORK_STATUSNET)
+			DBA::escape(Protocol::OSTATUS),
+			DBA::escape(Protocol::STATUSNET)
 		);
 	} elseif ($type == 'c') {
 		$r = q("SELECT `id`, `name`, `nick`, `micro`, `network`, `url`, `attag`, `addr`, `forum`, `prv` FROM `contact`
@@ -153,7 +154,7 @@ function acl_content(App $a)
 				$sql_extra2
 				ORDER BY `name` ASC ",
 			intval(local_user()),
-			DBA::escape(NETWORK_STATUSNET)
+			DBA::escape(Protocol::STATUSNET)
 		);
 	} elseif ($type == 'f') {
 		$r = q("SELECT `id`, `name`, `nick`, `micro`, `network`, `url`, `attag`, `addr`, `forum`, `prv` FROM `contact`
@@ -163,7 +164,7 @@ function acl_content(App $a)
 				$sql_extra2
 				ORDER BY `name` ASC ",
 			intval(local_user()),
-			DBA::escape(NETWORK_STATUSNET)
+			DBA::escape(Protocol::STATUSNET)
 		);
 	} elseif ($type == 'm') {
 		$r = q("SELECT `id`, `name`, `nick`, `micro`, `network`, `url`, `attag`, `addr` FROM `contact`
@@ -172,8 +173,8 @@ function acl_content(App $a)
 				$sql_extra2
 				ORDER BY `name` ASC ",
 			intval(local_user()),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA)
 		);
 	} elseif ($type == 'a') {
 		$r = q("SELECT `id`, `name`, `nick`, `micro`, `network`, `url`, `attag`, `addr`, `forum`, `prv` FROM `contact`
diff --git a/mod/contacts.php b/mod/contacts.php
index c5a43d4f2..9800dbdc1 100644
--- a/mod/contacts.php
+++ b/mod/contacts.php
@@ -10,6 +10,7 @@ use Friendica\Content\Text\BBCode;
 use Friendica\Content\Widget;
 use Friendica\Core\Addon;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -54,7 +55,7 @@ function contacts_init(App $a)
 
 		$a->data['contact'] = $contact;
 
-		if (($a->data['contact']['network'] != "") && ($a->data['contact']['network'] != NETWORK_DFRN)) {
+		if (($a->data['contact']['network'] != "") && ($a->data['contact']['network'] != Protocol::DFRN)) {
 			$networkname = format_network_name($a->data['contact']['network'], $a->data['contact']['url']);
 		} else {
 			$networkname = '';
@@ -248,7 +249,7 @@ function _contact_update($contact_id)
 
 	$uid = $contact["uid"];
 
-	if ($contact["network"] == NETWORK_OSTATUS) {
+	if ($contact["network"] == Protocol::OSTATUS) {
 		$result = Contact::createFromProbe($uid, $contact["url"], false, $contact["network"]);
 
 		if ($result['success']) {
@@ -272,7 +273,7 @@ function _contact_update_profile($contact_id)
 	$data = Probe::uri($contact["url"], "", 0, false);
 
 	// "Feed" or "Unknown" is mostly a sign of communication problems
-	if ((in_array($data["network"], [NETWORK_FEED, NETWORK_PHANTOM])) && ($data["network"] != $contact["network"])) {
+	if ((in_array($data["network"], [Protocol::FEED, Protocol::PHANTOM])) && ($data["network"] != $contact["network"])) {
 		return;
 	}
 
@@ -280,7 +281,7 @@ function _contact_update_profile($contact_id)
 		"poco", "network", "alias"];
 	$update = [];
 
-	if ($data["network"] == NETWORK_OSTATUS) {
+	if ($data["network"] == Protocol::OSTATUS) {
 		$result = Contact::createFromProbe($uid, $data["url"], false);
 
 		if ($result['success']) {
@@ -532,7 +533,7 @@ function contacts_content(App $a)
 				break;
 		}
 
-		if (!in_array($contact['network'], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_DIASPORA])) {
+		if (!in_array($contact['network'], [Protocol::DFRN, Protocol::OSTATUS, Protocol::DIASPORA])) {
 			$relation_text = "";
 		}
 
@@ -552,9 +553,9 @@ function contacts_content(App $a)
 		if ($contact['last-update'] > NULL_DATE) {
 			$last_update .= ' ' . (($contact['last-update'] <= $contact['success_update']) ? L10n::t("\x28Update was successful\x29") : L10n::t("\x28Update was not successful\x29"));
 		}
-		$lblsuggest = (($contact['network'] === NETWORK_DFRN) ? L10n::t('Suggest friends') : '');
+		$lblsuggest = (($contact['network'] === Protocol::DFRN) ? L10n::t('Suggest friends') : '');
 
-		$poll_enabled = in_array($contact['network'], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_FEED, NETWORK_MAIL]);
+		$poll_enabled = in_array($contact['network'], [Protocol::DFRN, Protocol::OSTATUS, Protocol::FEED, Protocol::MAIL]);
 
 		$nettype = L10n::t('Network type: %s', ContactSelector::networkToName($contact['network'], $contact["url"]));
 
@@ -564,7 +565,7 @@ function contacts_content(App $a)
 		$lost_contact = (($contact['archive'] && $contact['term-date'] > NULL_DATE && $contact['term-date'] < DateTimeFormat::utcNow()) ? L10n::t('Communications lost with this contact!') : '');
 
 		$fetch_further_information = null;
-		if ($contact['network'] == NETWORK_FEED) {
+		if ($contact['network'] == Protocol::FEED) {
 			$fetch_further_information = [
 				'fetch_further_information',
 				L10n::t('Fetch further information for feeds'),
@@ -579,19 +580,19 @@ function contacts_content(App $a)
 		}
 
 		$poll_interval = null;
-		if (in_array($contact['network'], [NETWORK_FEED, NETWORK_MAIL])) {
+		if (in_array($contact['network'], [Protocol::FEED, Protocol::MAIL])) {
 			$poll_interval = ContactSelector::pollInterval($contact['priority'], (!$poll_enabled));
 		}
 
 		$profile_select = null;
-		if ($contact['network'] == NETWORK_DFRN) {
-			$profile_select = ContactSelector::profileAssign($contact['profile-id'], (($contact['network'] !== NETWORK_DFRN) ? true : false));
+		if ($contact['network'] == Protocol::DFRN) {
+			$profile_select = ContactSelector::profileAssign($contact['profile-id'], (($contact['network'] !== Protocol::DFRN) ? true : false));
 		}
 
 		/// @todo Only show the following link with DFRN when the remote version supports it
 		$follow = '';
 		$follow_text = '';
-		if (in_array($contact['network'], [NETWORK_DIASPORA, NETWORK_OSTATUS, NETWORK_DFRN])) {
+		if (in_array($contact['network'], [Protocol::DIASPORA, Protocol::OSTATUS, Protocol::DFRN])) {
 			if ($contact['rel'] == Contact::FOLLOWER) {
 				$follow = System::baseUrl(true) . "/follow?url=" . urlencode($contact["url"]);
 				$follow_text = L10n::t("Connect/Follow");
@@ -637,7 +638,7 @@ function contacts_content(App $a)
 			'$contact_id' => $contact['id'],
 			'$block_text' => (($contact['blocked']) ? L10n::t('Unblock') : L10n::t('Block') ),
 			'$ignore_text' => (($contact['readonly']) ? L10n::t('Unignore') : L10n::t('Ignore') ),
-			'$insecure' => (($contact['network'] !== NETWORK_DFRN && $contact['network'] !== NETWORK_MAIL && $contact['network'] !== NETWORK_DIASPORA) ? $insecure : ''),
+			'$insecure' => (($contact['network'] !== Protocol::DFRN && $contact['network'] !== Protocol::MAIL && $contact['network'] !== Protocol::DIASPORA) ? $insecure : ''),
 			'$info' => $contact['info'],
 			'$cinfo' => ['info', '', $contact['info'], ''],
 			'$blocked' => (($contact['blocked']) ? L10n::t('Currently blocked') : ''),
@@ -991,11 +992,11 @@ function _contact_detail_for_template(array $rr)
  */
 function contact_actions($contact)
 {
-	$poll_enabled = in_array($contact['network'], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_FEED, NETWORK_MAIL]);
+	$poll_enabled = in_array($contact['network'], [Protocol::DFRN, Protocol::OSTATUS, Protocol::FEED, Protocol::MAIL]);
 	$contact_actions = [];
 
 	// Provide friend suggestion only for Friendica contacts
-	if ($contact['network'] === NETWORK_DFRN) {
+	if ($contact['network'] === Protocol::DFRN) {
 		$contact_actions['suggest'] = [
 			'label' => L10n::t('Suggest friends'),
 			'url'   => 'fsuggest/' . $contact['id'],
diff --git a/mod/crepair.php b/mod/crepair.php
index 309a356d5..37956421f 100644
--- a/mod/crepair.php
+++ b/mod/crepair.php
@@ -6,6 +6,7 @@
 use Friendica\App;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Profile;
@@ -122,17 +123,17 @@ function crepair_content(App $a)
 	// Disable remote self for everything except feeds.
 	// There is an issue when you repeat an item from maybe twitter and you got comments from friendica and twitter
 	// Problem is, you couldn't reply to both networks.
-	if (!in_array($contact['network'], [NETWORK_FEED, NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_TWITTER])) {
+	if (!in_array($contact['network'], [Protocol::FEED, Protocol::DFRN, Protocol::DIASPORA, Protocol::TWITTER])) {
 		$allow_remote_self = false;
 	}
 
-	if ($contact['network'] == NETWORK_FEED) {
+	if ($contact['network'] == Protocol::FEED) {
 		$remote_self_options = ['0' => L10n::t('No mirroring'), '1' => L10n::t('Mirror as forwarded posting'), '2' => L10n::t('Mirror as my own posting')];
 	} else {
 		$remote_self_options = ['0' => L10n::t('No mirroring'), '2' => L10n::t('Mirror as my own posting')];
 	}
 
-	$update_profile = in_array($contact['network'], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS]);
+	$update_profile = in_array($contact['network'], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS]);
 
 	$tab_str = contacts_tab($a, $contact['id'], 5);
 
diff --git a/mod/delegate.php b/mod/delegate.php
index d0fd78cec..ed4f85437 100644
--- a/mod/delegate.php
+++ b/mod/delegate.php
@@ -5,6 +5,7 @@
 
 use Friendica\App;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\User;
@@ -112,7 +113,7 @@ function delegate_content(App $a)
 		AND `network` = '%s' ",
 		DBA::escape(normalise_link(System::baseUrl())),
 		intval(local_user()),
-		DBA::escape(NETWORK_DFRN)
+		DBA::escape(Protocol::DFRN)
 	);
 	if (DBA::isResult($r)) {
 		$nicknames = [];
diff --git a/mod/dfrn_confirm.php b/mod/dfrn_confirm.php
index d8d742986..e2fbf1cdb 100644
--- a/mod/dfrn_confirm.php
+++ b/mod/dfrn_confirm.php
@@ -20,6 +20,7 @@
 use Friendica\App;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -136,13 +137,13 @@ function dfrn_confirm_post(App $a, $handsfree = null)
 		$dfrn_confirm = $contact['confirm'];
 		$aes_allow    = $contact['aes_allow'];
 
-		$network = ((strlen($contact['issued-id'])) ? NETWORK_DFRN : NETWORK_OSTATUS);
+		$network = ((strlen($contact['issued-id'])) ? Protocol::DFRN : Protocol::OSTATUS);
 
 		if ($contact['network']) {
 			$network = $contact['network'];
 		}
 
-		if ($network === NETWORK_DFRN) {
+		if ($network === Protocol::DFRN) {
 			/*
 			 * Generate a key pair for all further communications with this person.
 			 * We have a keypair for every contact, and a site key for unknown people.
@@ -304,7 +305,7 @@ function dfrn_confirm_post(App $a, $handsfree = null)
 
 		logger('dfrn_confirm: confirm - imported photos');
 
-		if ($network === NETWORK_DFRN) {
+		if ($network === Protocol::DFRN) {
 			$new_relation = Contact::FOLLOWER;
 			if (($relation == Contact::SHARING) || ($duplex)) {
 				$new_relation = Contact::FRIEND;
@@ -328,12 +329,12 @@ function dfrn_confirm_post(App $a, $handsfree = null)
 				DBA::escape(DateTimeFormat::utcNow()),
 				intval($duplex),
 				intval($hidden),
-				DBA::escape(NETWORK_DFRN),
+				DBA::escape(Protocol::DFRN),
 				intval($contact_id)
 			);
 		} else {
-			// $network !== NETWORK_DFRN
-			$network = defaults($contact, 'network', NETWORK_OSTATUS);
+			// $network !== Protocol::DFRN
+			$network = defaults($contact, 'network', Protocol::OSTATUS);
 
 			$arr = Probe::uri($contact['url']);
 
@@ -345,7 +346,7 @@ function dfrn_confirm_post(App $a, $handsfree = null)
 			$new_relation = $contact['rel'];
 			$writable = $contact['writable'];
 
-			if ($network === NETWORK_DIASPORA) {
+			if ($network === Protocol::DIASPORA) {
 				if ($duplex) {
 					$new_relation = Contact::FRIEND;
 				} else {
@@ -392,7 +393,7 @@ function dfrn_confirm_post(App $a, $handsfree = null)
 		// reload contact info
 		$contact = DBA::selectFirst('contact', [], ['id' => $contact_id]);
 		if ((isset($new_relation) && $new_relation == Contact::FRIEND)) {
-			if (DBA::isResult($contact) && ($contact['network'] === NETWORK_DIASPORA)) {
+			if (DBA::isResult($contact) && ($contact['network'] === Protocol::DIASPORA)) {
 				$ret = Diaspora::sendShare($user, $contact);
 				logger('share returns: ' . $ret);
 			}
@@ -573,7 +574,7 @@ function dfrn_confirm_post(App $a, $handsfree = null)
 			intval($duplex),
 			intval($forum),
 			intval($prv),
-			DBA::escape(NETWORK_DFRN),
+			DBA::escape(Protocol::DFRN),
 			intval($dfrn_record)
 		);
 		if (!DBA::isResult($r)) {	// indicates schema is messed up or total db failure
diff --git a/mod/dfrn_request.php b/mod/dfrn_request.php
index 484599f6f..25fe69066 100644
--- a/mod/dfrn_request.php
+++ b/mod/dfrn_request.php
@@ -15,6 +15,7 @@
 use Friendica\App;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -148,7 +149,7 @@ function dfrn_request_post(App $a)
 						$parms['dfrn-confirm'],
 						$parms['dfrn-notify'],
 						$parms['dfrn-poll'],
-						DBA::escape(NETWORK_DFRN),
+						DBA::escape(Protocol::DFRN),
 						intval($aes_allow),
 						intval($hidden),
 						intval($blocked),
@@ -287,18 +288,18 @@ function dfrn_request_post(App $a)
 			// Every time we detect the remote subscription we define this as OStatus.
 			// We do this even if it is not OStatus.
 			// we only need to pass this through another section of the code.
-			if ($network != NETWORK_DIASPORA) {
-				$network = NETWORK_OSTATUS;
+			if ($network != Protocol::DIASPORA) {
+				$network = Protocol::OSTATUS;
 			}
 
 			$url = substr($url, 5);
 		} else {
-			$network = NETWORK_DFRN;
+			$network = Protocol::DFRN;
 		}
 
 		logger('dfrn_request: url: ' . $url . ',network=' . $network, LOGGER_DEBUG);
 
-		if ($network === NETWORK_DFRN) {
+		if ($network === Protocol::DFRN) {
 			$ret = q("SELECT * FROM `contact` WHERE `uid` = %d AND `url` = '%s' AND `self` = 0 LIMIT 1",
 				intval($uid),
 				DBA::escape($url)
@@ -388,7 +389,7 @@ function dfrn_request_post(App $a)
 					$parms['dfrn-confirm'],
 					$parms['dfrn-notify'],
 					$parms['dfrn-poll'],
-					DBA::escape(NETWORK_DFRN),
+					DBA::escape(Protocol::DFRN),
 					intval($blocked),
 					intval($pending)
 				);
@@ -441,15 +442,15 @@ function dfrn_request_post(App $a)
 				. (($aes_allow) ? "&aes_allow=1" : "")
 			);
 			// NOTREACHED
-			// END $network === NETWORK_DFRN
-		} elseif (($network != NETWORK_PHANTOM) && ($url != "")) {
+			// END $network === Protocol::DFRN
+		} elseif (($network != Protocol::PHANTOM) && ($url != "")) {
 
 			/* Substitute our user's feed URL into $url template
 			 * Send the subscriber home to subscribe
 			 */
 			// Diaspora needs the uri in the format user@domain.tld
 			// Diaspora will support the remote subscription in a future version
-			if ($network == NETWORK_DIASPORA) {
+			if ($network == Protocol::DIASPORA) {
 				$uri = $nickname . '@' . $a->get_hostname();
 
 				if ($a->get_path()) {
@@ -464,7 +465,7 @@ function dfrn_request_post(App $a)
 			$url = str_replace('{uri}', $uri, $url);
 			goaway($url);
 			// NOTREACHED
-			// END $network != NETWORK_PHANTOM
+			// END $network != Protocol::PHANTOM
 		} else {
 			notice(L10n::t("Remote subscription can't be done for your network. Please subscribe directly on your system.") . EOL);
 			return;
diff --git a/mod/dirfind.php b/mod/dirfind.php
index 2d728f8e7..fd31b2cbf 100644
--- a/mod/dirfind.php
+++ b/mod/dirfind.php
@@ -8,6 +8,7 @@ use Friendica\Content\ContactSelector;
 use Friendica\Content\Widget;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -53,7 +54,7 @@ function dirfind_content(App $a, $prefix = "") {
 		if ((valid_email($search) && Network::isEmailDomainValid($search)) ||
 			(substr(normalise_link($search), 0, 7) == "http://")) {
 			$user_data = Probe::uri($search);
-			$discover_user = (in_array($user_data["network"], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_DIASPORA]));
+			$discover_user = (in_array($user_data["network"], [Protocol::DFRN, Protocol::OSTATUS, Protocol::DIASPORA]));
 		}
 	}
 
@@ -102,15 +103,15 @@ function dirfind_content(App $a, $prefix = "") {
 			$startrec = (($a->pager['page']) * $perpage) - $perpage;
 
 			if (Config::get('system','diaspora_enabled')) {
-				$diaspora = NETWORK_DIASPORA;
+				$diaspora = Protocol::DIASPORA;
 			} else {
-				$diaspora = NETWORK_DFRN;
+				$diaspora = Protocol::DFRN;
 			}
 
 			if (!Config::get('system','ostatus_disabled')) {
-				$ostatus = NETWORK_OSTATUS;
+				$ostatus = Protocol::OSTATUS;
 			} else {
-				$ostatus = NETWORK_DFRN;
+				$ostatus = Protocol::DFRN;
 			}
 
 			$search2 = "%".$search."%";
@@ -121,7 +122,7 @@ function dirfind_content(App $a, $prefix = "") {
 						((`last_contact` >= `last_failure`) OR (`updated` >= `last_failure`)) AND
 						(`url` LIKE '%s' OR `name` LIKE '%s' OR `location` LIKE '%s' OR
 						`addr` LIKE '%s' OR `about` LIKE '%s' OR `keywords` LIKE '%s') $extra_sql",
-					DBA::escape(NETWORK_DFRN), DBA::escape($ostatus), DBA::escape($diaspora),
+					DBA::escape(Protocol::DFRN), DBA::escape($ostatus), DBA::escape($diaspora),
 					DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)),
 					DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)));
 
@@ -133,7 +134,7 @@ function dirfind_content(App $a, $prefix = "") {
 						`addr` LIKE '%s' OR `about` LIKE '%s' OR `keywords` LIKE '%s') $extra_sql
 						GROUP BY `nurl`
 						ORDER BY `updated` DESC LIMIT %d, %d",
-					DBA::escape(NETWORK_DFRN), DBA::escape($ostatus), DBA::escape($diaspora),
+					DBA::escape(Protocol::DFRN), DBA::escape($ostatus), DBA::escape($diaspora),
 					DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)),
 					DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)), DBA::escape(escape_tags($search2)),
 					intval($startrec), intval($perpage));
diff --git a/mod/display.php b/mod/display.php
index d57b151bc..c30e22626 100644
--- a/mod/display.php
+++ b/mod/display.php
@@ -94,7 +94,7 @@ function display_init(App $a)
 			if (DBA::isResult($profile)) {
 				$profiledata = $profile;
 			}
-			$profiledata["network"] = NETWORK_DFRN;
+			$profiledata["network"] = Protocol::DFRN;
 		} else {
 			$profiledata = [];
 		}
@@ -177,10 +177,10 @@ function display_fetchauthor($a, $item)
 	$profiledata["photo"] = System::removedBaseUrl($profiledata["photo"]);
 
 	if (local_user()) {
-		if (in_array($profiledata["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])) {
+		if (in_array($profiledata["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])) {
 			$profiledata["remoteconnect"] = System::baseUrl()."/follow?url=".urlencode($profiledata["url"]);
 		}
-	} elseif ($profiledata["network"] == NETWORK_DFRN) {
+	} elseif ($profiledata["network"] == Protocol::DFRN) {
 		$connect = str_replace("/profile/", "/dfrn_request/", $profiledata["url"]);
 		$profiledata["remoteconnect"] = $connect;
 	}
diff --git a/mod/fetch.php b/mod/fetch.php
index 36f9eef70..35455e282 100644
--- a/mod/fetch.php
+++ b/mod/fetch.php
@@ -5,6 +5,7 @@ This file is part of the Diaspora protocol. It is used for fetching single publi
 
 use Friendica\App;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Protocol\Diaspora;
 use Friendica\Model\Item;
@@ -25,10 +26,10 @@ function fetch_init(App $a)
 	// Fetch the item
 	$fields = ['uid', 'title', 'body', 'guid', 'contact-id', 'private', 'created', 'app', 'location', 'coord', 'network',
 		'event-id', 'resource-id', 'author-link', 'owner-link', 'attach'];
-	$condition = ['wall' => true, 'private' => false, 'guid' => $guid, 'network' => [NETWORK_DFRN, NETWORK_DIASPORA]];
+	$condition = ['wall' => true, 'private' => false, 'guid' => $guid, 'network' => [Protocol::DFRN, Protocol::DIASPORA]];
 	$item = Item::selectFirst($fields, $condition);
 	if (!DBA::isResult($item)) {
-		$condition = ['guid' => $guid, 'network' => [NETWORK_DFRN, NETWORK_DIASPORA]];
+		$condition = ['guid' => $guid, 'network' => [Protocol::DFRN, Protocol::DIASPORA]];
 		$item = Item::selectFirst(['author-link'], $condition);
 		if (DBA::isResult($item)) {
 			$parts = parse_url($item["author-link"]);
diff --git a/mod/follow.php b/mod/follow.php
index 15a5b2f40..ef2325ad0 100644
--- a/mod/follow.php
+++ b/mod/follow.php
@@ -5,6 +5,7 @@
 use Friendica\App;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Model\Contact;
 use Friendica\Model\Profile;
@@ -66,8 +67,8 @@ function follow_content(App $a)
 	$r = q("SELECT `pending` FROM `contact` WHERE `uid` = %d AND ((`rel` != %d) OR (`network` = '%s')) AND
 		(`nurl` = '%s' OR `alias` = '%s' OR `alias` = '%s') AND
 		`network` != '%s' LIMIT 1",
-		intval(local_user()), DBA::escape(Contact::FOLLOWER), DBA::escape(NETWORK_DFRN), DBA::escape(normalise_link($url)),
-		DBA::escape(normalise_link($url)), DBA::escape($url), DBA::escape(NETWORK_STATUSNET));
+		intval(local_user()), DBA::escape(Contact::FOLLOWER), DBA::escape(Protocol::DFRN), DBA::escape(normalise_link($url)),
+		DBA::escape(normalise_link($url)), DBA::escape($url), DBA::escape(Protocol::STATUSNET));
 
 	if ($r) {
 		if ($r[0]['pending']) {
@@ -80,32 +81,32 @@ function follow_content(App $a)
 
 	$ret = Probe::uri($url);
 
-	if (($ret['network'] == NETWORK_DIASPORA) && !Config::get('system', 'diaspora_enabled')) {
+	if (($ret['network'] == Protocol::DIASPORA) && !Config::get('system', 'diaspora_enabled')) {
 		notice(L10n::t("Diaspora support isn't enabled. Contact can't be added."));
 		$submit = '';
 		//goaway($_SESSION['return_url']);
 		// NOTREACHED
 	}
 
-	if (($ret['network'] == NETWORK_OSTATUS) && Config::get('system', 'ostatus_disabled')) {
+	if (($ret['network'] == Protocol::OSTATUS) && Config::get('system', 'ostatus_disabled')) {
 		notice(L10n::t("OStatus support is disabled. Contact can't be added."));
 		$submit = '';
 		//goaway($_SESSION['return_url']);
 		// NOTREACHED
 	}
 
-	if ($ret['network'] == NETWORK_PHANTOM) {
+	if ($ret['network'] == Protocol::PHANTOM) {
 		notice(L10n::t("The network type couldn't be detected. Contact can't be added."));
 		$submit = '';
 		//goaway($_SESSION['return_url']);
 		// NOTREACHED
 	}
 
-	if ($ret['network'] == NETWORK_MAIL) {
+	if ($ret['network'] == Protocol::MAIL) {
 		$ret['url'] = $ret['addr'];
 	}
 
-	if (($ret['network'] === NETWORK_DFRN) && !DBA::isResult($r)) {
+	if (($ret['network'] === Protocol::DFRN) && !DBA::isResult($r)) {
 		$request = $ret['request'];
 		$tpl = get_markup_template('dfrn_request.tpl');
 	} else {
@@ -136,7 +137,7 @@ function follow_content(App $a)
 		$gcontact_id = $r[0]['id'];
 	}
 
-	if ($ret['network'] === NETWORK_DIASPORA) {
+	if ($ret['network'] === Protocol::DIASPORA) {
 		$r[0]['location'] = '';
 		$r[0]['about'] = '';
 	}
diff --git a/mod/item.php b/mod/item.php
index 685a16143..125606d27 100644
--- a/mod/item.php
+++ b/mod/item.php
@@ -21,6 +21,7 @@ use Friendica\Content\Text\HTML;
 use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -158,7 +159,7 @@ function item_post(App $a) {
 	}
 
 	// Allow commenting if it is an answer to a public post
-	$allow_comment = local_user() && ($profile_uid == 0) && $parent && in_array($parent_item['network'], [NETWORK_OSTATUS, NETWORK_DIASPORA, NETWORK_DFRN]);
+	$allow_comment = local_user() && ($profile_uid == 0) && $parent && in_array($parent_item['network'], [Protocol::OSTATUS, Protocol::DIASPORA, Protocol::DFRN]);
 
 	// Now check that valid personal details have been provided
 	if (!can_write_wall($profile_uid) && !$allow_comment) {
@@ -238,7 +239,7 @@ function item_post(App $a) {
 		$verb              =      notags(trim(defaults($_REQUEST, 'verb'    , '')));
 		$emailcc           =      notags(trim(defaults($_REQUEST, 'emailcc' , '')));
 		$body              = escape_tags(trim(defaults($_REQUEST, 'body'    , '')));
-		$network           =      notags(trim(defaults($_REQUEST, 'network' , NETWORK_DFRN)));
+		$network           =      notags(trim(defaults($_REQUEST, 'network' , Protocol::DFRN)));
 		$guid              =      System::createGUID(32);
 
 		$postopts = defaults($_REQUEST, 'postopts', '');
@@ -253,8 +254,8 @@ function item_post(App $a) {
 
 		if ($parent_item) {
 			// for non native networks use the network of the original post as network of the item
-			if (($parent_item['network'] != NETWORK_DIASPORA)
-				&& ($parent_item['network'] != NETWORK_OSTATUS)
+			if (($parent_item['network'] != Protocol::DIASPORA)
+				&& ($parent_item['network'] != Protocol::OSTATUS)
 				&& ($network == "")) {
 				$network = $parent_item['network'];
 			}
@@ -344,14 +345,14 @@ function item_post(App $a) {
 
 	// Add a tag if the parent contact is from OStatus (This will notify them during delivery)
 	if ($parent) {
-		if ($thr_parent_contact['network'] == NETWORK_OSTATUS) {
+		if ($thr_parent_contact['network'] == Protocol::OSTATUS) {
 			$contact = '@[url=' . $thr_parent_contact['url'] . ']' . $thr_parent_contact['nick'] . '[/url]';
 			if (!stripos(implode($tags), '[url=' . $thr_parent_contact['url'] . ']')) {
 				$tags[] = $contact;
 			}
 		}
 
-		if ($parent_contact['network'] == NETWORK_OSTATUS) {
+		if ($parent_contact['network'] == Protocol::OSTATUS) {
 			$contact = '@[url=' . $parent_contact['url'] . ']' . $parent_contact['nick'] . '[/url]';
 			if (!stripos(implode($tags), '[url=' . $parent_contact['url'] . ']')) {
 				$tags[] = $contact;
@@ -559,7 +560,7 @@ function item_post(App $a) {
 	}
 
 	if ($network == "") {
-		$network = NETWORK_DFRN;
+		$network = Protocol::DFRN;
 	}
 
 	$gravity = ($parent ? GRAVITY_COMMENT : GRAVITY_PARENT);
@@ -674,7 +675,7 @@ function item_post(App $a) {
 		// doesn't have an ID.
 		$datarray["id"] = -1;
 		$datarray["item_id"] = -1;
-		$datarray["author-network"] = NETWORK_DFRN;
+		$datarray["author-network"] = Protocol::DFRN;
 
 		$o = conversation($a,[array_merge($contact_record,$datarray)],'search', false, true);
 		logger('preview: ' . $o);
@@ -1021,8 +1022,8 @@ function handle_tag(App $a, &$body, &$inform, &$str_tags, $profile_uid, $tag, $n
 			$alias   = $contact["alias"];
 			$newname = $contact["nick"];
 
-			if (($newname == "") || (($contact["network"] != NETWORK_OSTATUS) && ($contact["network"] != NETWORK_TWITTER)
-				&& ($contact["network"] != NETWORK_STATUSNET))) {
+			if (($newname == "") || (($contact["network"] != Protocol::OSTATUS) && ($contact["network"] != Protocol::TWITTER)
+				&& ($contact["network"] != Protocol::STATUSNET))) {
 				$newname = $contact["name"];
 			}
 		}
diff --git a/mod/network.php b/mod/network.php
index 4609674fc..49f9c7cb1 100644
--- a/mod/network.php
+++ b/mod/network.php
@@ -14,6 +14,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -664,7 +665,7 @@ function networkThreadedView(App $a, $update, $parent)
 				'id' => 'network',
 			]) . $o;
 
-			if ($contact['network'] === NETWORK_OSTATUS && $contact['writable'] && !PConfig::get(local_user(),'system','nowarn_insecure')) {
+			if ($contact['network'] === Protocol::OSTATUS && $contact['writable'] && !PConfig::get(local_user(),'system','nowarn_insecure')) {
 				notice(L10n::t('Private messages to this person are at risk of public disclosure.') . EOL);
 			}
 		} else {
@@ -805,7 +806,7 @@ function networkThreadedView(App $a, $update, $parent)
 	}
 
 	// Only show it when unfiltered (no groups, no networks, ...)
-	if (in_array($nets, ['', NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS]) && (strlen($sql_extra . $sql_extra2 . $sql_extra3) == 0)) {
+	if (in_array($nets, ['', Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS]) && (strlen($sql_extra . $sql_extra2 . $sql_extra3) == 0)) {
 		if (DBA::isResult($r)) {
 			$top_limit = current($r)['order_date'];
 			$bottom_limit = end($r)['order_date'];
diff --git a/mod/noscrape.php b/mod/noscrape.php
index a948bee4f..3a8abe229 100644
--- a/mod/noscrape.php
+++ b/mod/noscrape.php
@@ -4,6 +4,7 @@
  */
 
 use Friendica\App;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -62,9 +63,9 @@ function noscrape_init(App $a)
 		$r = q("SELECT COUNT(*) AS `total` FROM `contact` WHERE `uid` = %d AND `self` = 0 AND `blocked` = 0 and `pending` = 0 AND `hidden` = 0 AND `archive` = 0
 				AND `network` IN ('%s', '%s', '%s', '')",
 			intval($a->profile['uid']),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_OSTATUS)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::OSTATUS)
 		);
 		if (DBA::isResult($r)) {
 			$json_info["contacts"] = intval($r[0]['total']);
diff --git a/mod/notifications.php b/mod/notifications.php
index e906f9385..52521b017 100644
--- a/mod/notifications.php
+++ b/mod/notifications.php
@@ -9,6 +9,7 @@ use Friendica\Content\ContactSelector;
 use Friendica\Content\Nav;
 use Friendica\Core\L10n;
 use Friendica\Core\NotificationsManager;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 
@@ -181,8 +182,8 @@ function notifications_content(App $a)
 
 				// Normal connection requests
 				default:
-					$friend_selected = (($it['network'] !== NETWORK_OSTATUS) ? ' checked="checked" ' : ' disabled ');
-					$fan_selected = (($it['network'] === NETWORK_OSTATUS) ? ' checked="checked" disabled ' : '');
+					$friend_selected = (($it['network'] !== Protocol::OSTATUS) ? ' checked="checked" ' : ' disabled ');
+					$fan_selected = (($it['network'] === Protocol::OSTATUS) ? ' checked="checked" disabled ' : '');
 					$dfrn_tpl = get_markup_template('netfriend.tpl');
 
 					$knowyou   = '';
@@ -192,8 +193,8 @@ function notifications_content(App $a)
 					$helptext2 = '';
 					$helptext3 = '';
 
-					if ($it['network'] === NETWORK_DFRN || $it['network'] === NETWORK_DIASPORA) {
-						if ($it['network'] === NETWORK_DFRN) {
+					if ($it['network'] === Protocol::DFRN || $it['network'] === Protocol::DIASPORA) {
+						if ($it['network'] === Protocol::DFRN) {
 							$lbl_knowyou = L10n::t('Claims to be known to you: ');
 							$knowyou = (($it['knowyou']) ? L10n::t('yes') : L10n::t('no'));
 							$helptext = L10n::t('Shall your connection be bidirectional or not?');
@@ -215,7 +216,7 @@ function notifications_content(App $a)
 						'$approve_as2' => $helptext2,
 						'$approve_as3' => $helptext3,
 						'$as_friend' => L10n::t('Friend'),
-						'$as_fan' => (($it['network'] == NETWORK_DIASPORA) ? L10n::t('Sharer') : L10n::t('Subscriber'))
+						'$as_fan' => (($it['network'] == Protocol::DIASPORA) ? L10n::t('Sharer') : L10n::t('Subscriber'))
 					]);
 
 					$header = $it["name"];
@@ -226,7 +227,7 @@ function notifications_content(App $a)
 
 					$header .= " (".ContactSelector::networkToName($it['network'], $it['url']).")";
 
-					if ($it['network'] != NETWORK_DIASPORA) {
+					if ($it['network'] != Protocol::DIASPORA) {
 						$discard = L10n::t('Discard');
 					} else {
 						$discard = '';
diff --git a/mod/ostatus_subscribe.php b/mod/ostatus_subscribe.php
index e8ba144a1..987f31699 100644
--- a/mod/ostatus_subscribe.php
+++ b/mod/ostatus_subscribe.php
@@ -5,6 +5,7 @@
 use Friendica\App;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Model\Contact;
 use Friendica\Network\Probe;
@@ -72,8 +73,8 @@ function ostatus_subscribe_content(App $a) {
 	$o .= "<p>".$counter."/".$total.": ".$url;
 
 	$data = Probe::uri($url);
-	if ($data["network"] == NETWORK_OSTATUS) {
-		$result = Contact::createFromProbe($uid, $url, true, NETWORK_OSTATUS);
+	if ($data["network"] == Protocol::OSTATUS) {
+		$result = Contact::createFromProbe($uid, $url, true, Protocol::OSTATUS);
 		if ($result["success"]) {
 			$o .= " - ".L10n::t("success");
 		} else {
diff --git a/mod/poco.php b/mod/poco.php
index a2f038d08..a16495326 100644
--- a/mod/poco.php
+++ b/mod/poco.php
@@ -8,6 +8,7 @@ use Friendica\App;
 use Friendica\Content\Text\BBCode;
 use Friendica\Core\Cache;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Protocol\PortableContact;
@@ -89,9 +90,9 @@ function poco_init(App $a) {
 	if ($global) {
 		$contacts = q("SELECT count(*) AS `total` FROM `gcontact` WHERE `updated` >= '%s' AND `updated` >= `last_failure` AND NOT `hide` AND `network` IN ('%s', '%s', '%s')",
 			DBA::escape($update_limit),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_OSTATUS)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::OSTATUS)
 		);
 	} elseif ($system_mode) {
 		$contacts = q("SELECT count(*) AS `total` FROM `contact` WHERE `self` = 1
@@ -101,10 +102,10 @@ function poco_init(App $a) {
 			AND (`success_update` >= `failure_update` OR `last-item` >= `failure_update`)
 			AND `network` IN ('%s', '%s', '%s', '%s') $sql_extra",
 			intval($user['uid']),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_OSTATUS),
-			DBA::escape(NETWORK_STATUSNET)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::OSTATUS),
+			DBA::escape(Protocol::STATUSNET)
 		);
 	}
 	if (DBA::isResult($contacts)) {
@@ -124,9 +125,9 @@ function poco_init(App $a) {
 		$contacts = q("SELECT * FROM `gcontact` WHERE `updated` > '%s' AND NOT `hide` AND `network` IN ('%s', '%s', '%s') AND `updated` > `last_failure`
 			ORDER BY `updated` DESC LIMIT %d, %d",
 			DBA::escape($update_limit),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_OSTATUS),
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::OSTATUS),
 			intval($startIndex),
 			intval($itemsPerPage)
 		);
@@ -148,10 +149,10 @@ function poco_init(App $a) {
 			AND (`success_update` >= `failure_update` OR `last-item` >= `failure_update`)
 			AND `network` IN ('%s', '%s', '%s', '%s') $sql_extra LIMIT %d, %d",
 			intval($user['uid']),
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_OSTATUS),
-			DBA::escape(NETWORK_STATUSNET),
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::OSTATUS),
+			DBA::escape(Protocol::STATUSNET),
 			intval($startIndex),
 			intval($itemsPerPage)
 		);
@@ -257,7 +258,7 @@ function poco_init(App $a) {
 				}
 
 				// Non connected persons can only see the keywords of a Diaspora account
-				if ($contact['network'] == NETWORK_DIASPORA) {
+				if ($contact['network'] == Protocol::DIASPORA) {
 					$contact['location'] = "";
 					$about = "";
 					$contact['gender'] = "";
@@ -284,7 +285,7 @@ function poco_init(App $a) {
 				}
 				if ($fields_ret['urls']) {
 					$entry['urls'] = [['value' => $contact['url'], 'type' => 'profile']];
-					if ($contact['addr'] && ($contact['network'] !== NETWORK_MAIL)) {
+					if ($contact['addr'] && ($contact['network'] !== Protocol::MAIL)) {
 						$entry['urls'][] = ['value' => 'acct:' . $contact['addr'], 'type' => 'webfinger'];
 					}
 				}
@@ -314,11 +315,11 @@ function poco_init(App $a) {
 				}
 				if ($fields_ret['network']) {
 					$entry['network'] = $contact['network'];
-					if ($entry['network'] == NETWORK_STATUSNET) {
-						$entry['network'] = NETWORK_OSTATUS;
+					if ($entry['network'] == Protocol::STATUSNET) {
+						$entry['network'] = Protocol::OSTATUS;
 					}
 					if (($entry['network'] == "") && ($contact['self'])) {
-						$entry['network'] = NETWORK_DFRN;
+						$entry['network'] = Protocol::DFRN;
 					}
 				}
 				if ($fields_ret['tags']) {
diff --git a/mod/profperm.php b/mod/profperm.php
index 6ad922b59..4ee933e6c 100644
--- a/mod/profperm.php
+++ b/mod/profperm.php
@@ -6,6 +6,7 @@ use Friendica\App;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Profile;
 
@@ -30,7 +31,7 @@ function profperm_content(App $a) {
 	}
 
 
-	if($a->argc < 2) {
+	if ($a->argc < 2) {
 		notice(L10n::t('Invalid profile identifier.') . EOL );
 		return;
 	}
@@ -47,16 +48,18 @@ function profperm_content(App $a) {
 	if(($a->argc > 2) && intval($a->argv[1]) && intval($a->argv[2])) {
 		$r = q("SELECT `id` FROM `contact` WHERE `blocked` = 0 AND `pending` = 0 AND `self` = 0
 			AND `network` = '%s' AND `id` = %d AND `uid` = %d LIMIT 1",
-			DBA::escape(NETWORK_DFRN),
+			DBA::escape(Protocol::DFRN),
 			intval($a->argv[2]),
 			intval(local_user())
 		);
-		if (DBA::isResult($r))
+
+		if (DBA::isResult($r)) {
 			$change = intval($a->argv[2]);
+		}
 	}
 
 
-	if(($a->argc > 1) && (intval($a->argv[1]))) {
+	if (($a->argc > 1) && (intval($a->argv[1]))) {
 		$r = q("SELECT * FROM `profile` WHERE `id` = %d AND `uid` = %d AND `is-default` = 0 LIMIT 1",
 			intval($a->argv[1]),
 			intval(local_user())
@@ -144,7 +147,7 @@ function profperm_content(App $a) {
 		$r = q("SELECT * FROM `contact` WHERE `uid` = %d AND `blocked` = 0 and `pending` = 0 and `self` = 0
 			AND `network` = '%s' ORDER BY `name` ASC",
 			intval(local_user()),
-			DBA::escape(NETWORK_DFRN)
+			DBA::escape(Protocol::DFRN)
 		);
 
 		if (DBA::isResult($r)) {
diff --git a/mod/pubsub.php b/mod/pubsub.php
index ef97bb7f7..bc284a4eb 100644
--- a/mod/pubsub.php
+++ b/mod/pubsub.php
@@ -1,6 +1,7 @@
 <?php
 
 use Friendica\App;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Protocol\OStatus;
@@ -114,14 +115,14 @@ function pubsub_post(App $a)
 		}
 	}
 
-	if (!in_array($contact['rel'], [Contact::SHARING, Contact::FRIEND]) && ($contact['network'] != NETWORK_FEED)) {
+	if (!in_array($contact['rel'], [Contact::SHARING, Contact::FRIEND]) && ($contact['network'] != Protocol::FEED)) {
 		logger('Contact ' . $contact['id'] . ' is not expected to share with us - ignored.');
 		hub_post_return();
 	}
 
 	// We import feeds from OStatus, Friendica and ATOM/RSS.
 	/// @todo Check if Friendica posts really arrive here - otherwise we can discard some stuff
-	if (!in_array($contact['network'], [NETWORK_OSTATUS, NETWORK_DFRN, NETWORK_FEED])) {
+	if (!in_array($contact['network'], [Protocol::OSTATUS, Protocol::DFRN, Protocol::FEED])) {
 		hub_post_return();
 	}
 
@@ -130,7 +131,7 @@ function pubsub_post(App $a)
 	consume_feed($xml, $importer, $contact, $feedhub);
 
 	// do it a second time for DFRN so that any children find their parents.
-	if ($contact['network'] === NETWORK_DFRN) {
+	if ($contact['network'] === Protocol::DFRN) {
 		consume_feed($xml, $importer, $contact, $feedhub);
 	}
 
diff --git a/mod/redir.php b/mod/redir.php
index 0272ff1c8..727b70d66 100644
--- a/mod/redir.php
+++ b/mod/redir.php
@@ -2,6 +2,7 @@
 
 use Friendica\App;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -31,7 +32,7 @@ function redir_init(App $a) {
 
 		$contact_url = $contact['url'];
 
-		if ($contact['network'] !== NETWORK_DFRN // Authentication isn't supported for non DFRN contacts.
+		if ($contact['network'] !== Protocol::DFRN // Authentication isn't supported for non DFRN contacts.
 			|| (!local_user() && !remote_user()) // Visitors (not logged in or not remotes) can't authenticate.
 			|| (!empty($a->contact['id']) && $a->contact['id'] == $cid)) // Local user is already authenticated.
 		{
diff --git a/mod/repair_ostatus.php b/mod/repair_ostatus.php
index 7531ad35c..a1695127e 100644
--- a/mod/repair_ostatus.php
+++ b/mod/repair_ostatus.php
@@ -5,6 +5,7 @@
 
 use Friendica\App;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -28,7 +29,7 @@ function repair_ostatus_content(App $a) {
         $r = q("SELECT COUNT(*) AS `total` FROM `contact` WHERE
                 `uid` = %d AND `network` = '%s' AND `rel` IN (%d, %d)",
                 intval($uid),
-                DBA::escape(NETWORK_OSTATUS),
+                DBA::escape(Protocol::OSTATUS),
                 intval(Contact::FRIEND),
                 intval(Contact::SHARING));
 
@@ -42,7 +43,7 @@ function repair_ostatus_content(App $a) {
 		ORDER BY `url`
 		LIMIT %d, 1",
                 intval($uid),
-                DBA::escape(NETWORK_OSTATUS),
+                DBA::escape(Protocol::OSTATUS),
                 intval(Contact::FRIEND),
                 intval(Contact::SHARING), $counter++);
 
diff --git a/mod/salmon.php b/mod/salmon.php
index d1f9cf9a3..8bdfdefee 100644
--- a/mod/salmon.php
+++ b/mod/salmon.php
@@ -4,6 +4,7 @@
  */
 use Friendica\App;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -145,8 +146,8 @@ function salmon_post(App $a, $xml = '') {
 	$r = q("SELECT * FROM `contact` WHERE `network` IN ('%s', '%s')
 						AND (`nurl` = '%s' OR `alias` = '%s' OR `alias` = '%s')
 						AND `uid` = %d LIMIT 1",
-		DBA::escape(NETWORK_OSTATUS),
-		DBA::escape(NETWORK_DFRN),
+		DBA::escape(Protocol::OSTATUS),
+		DBA::escape(Protocol::DFRN),
 		DBA::escape(normalise_link($author_link)),
 		DBA::escape($author_link),
 		DBA::escape(normalise_link($author_link)),
@@ -159,7 +160,7 @@ function salmon_post(App $a, $xml = '') {
 			if($result['success']) {
 				$r = q("SELECT * FROM `contact` WHERE `network` = '%s' AND ( `url` = '%s' OR `alias` = '%s')
 					AND `uid` = %d LIMIT 1",
-					DBA::escape(NETWORK_OSTATUS),
+					DBA::escape(Protocol::OSTATUS),
 					DBA::escape($author_link),
 					DBA::escape($author_link),
 					intval($importer['uid'])
diff --git a/mod/unfollow.php b/mod/unfollow.php
index f4e4316d6..5c00726e2 100644
--- a/mod/unfollow.php
+++ b/mod/unfollow.php
@@ -5,6 +5,7 @@
 
 use Friendica\App;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -28,13 +29,13 @@ function unfollow_post(App $a)
 
 	$condition = ["`uid` = ? AND `rel` = ? AND (`nurl` = ? OR `alias` = ? OR `alias` = ?) AND `network` != ?",
 			$uid, Contact::FRIEND, normalise_link($url),
-			normalise_link($url), $url, NETWORK_STATUSNET];
+			normalise_link($url), $url, Protocol::STATUSNET];
 	$contact = DBA::selectFirst('contact', [], $condition);
 
 	if (!DBA::isResult($contact)) {
 		notice(L10n::t("Contact wasn't found or can't be unfollowed."));
 	} else {
-		if (in_array($contact['network'], [NETWORK_OSTATUS, NETWORK_DIASPORA, NETWORK_DFRN])) {
+		if (in_array($contact['network'], [Protocol::OSTATUS, Protocol::DIASPORA, Protocol::DFRN])) {
 			$r = q("SELECT `contact`.*, `user`.* FROM `contact` INNER JOIN `user` ON `contact`.`uid` = `user`.`uid`
 				WHERE `user`.`uid` = %d AND `contact`.`self` LIMIT 1",
 				intval($uid)
@@ -67,7 +68,8 @@ function unfollow_content(App $a)
 
 	$condition = ["`uid` = ? AND `rel` = ? AND (`nurl` = ? OR `alias` = ? OR `alias` = ?) AND `network` != ?",
 			local_user(), Contact::FRIEND, normalise_link($url),
-			normalise_link($url), $url, NETWORK_STATUSNET];
+			normalise_link($url), $url, Protocol::STATUSNET];
+
 	$contact = DBA::selectFirst('contact', ['url', 'network', 'addr', 'name'], $condition);
 
 	if (!DBA::isResult($contact)) {
@@ -76,7 +78,7 @@ function unfollow_content(App $a)
 		// NOTREACHED
 	}
 
-	if (!in_array($contact['network'], [NETWORK_DIASPORA, NETWORK_OSTATUS, NETWORK_DFRN])) {
+	if (!in_array($contact['network'], [Protocol::DIASPORA, Protocol::OSTATUS, Protocol::DFRN])) {
 		notice(L10n::t("Unfollowing is currently not supported by your network.").EOL);
 		$submit = "";
 		// NOTREACHED
diff --git a/mod/viewcontacts.php b/mod/viewcontacts.php
index 3b3579ce7..9219f49d9 100644
--- a/mod/viewcontacts.php
+++ b/mod/viewcontacts.php
@@ -7,6 +7,7 @@ use Friendica\Content\ContactSelector;
 use Friendica\Content\Nav;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Profile;
@@ -65,9 +66,9 @@ function viewcontacts_content(App $a)
 			AND NOT `hidden` AND NOT `archive`
 			AND `network` IN ('%s', '%s', '%s')",
 		intval($a->profile['uid']),
-		DBA::escape(NETWORK_DFRN),
-		DBA::escape(NETWORK_DIASPORA),
-		DBA::escape(NETWORK_OSTATUS)
+		DBA::escape(Protocol::DFRN),
+		DBA::escape(Protocol::DIASPORA),
+		DBA::escape(Protocol::OSTATUS)
 	);
 	if (DBA::isResult($r)) {
 		$a->set_pager_total($r[0]['total']);
@@ -79,9 +80,9 @@ function viewcontacts_content(App $a)
 			AND `network` IN ('%s', '%s', '%s')
 		ORDER BY `name` ASC LIMIT %d, %d",
 		intval($a->profile['uid']),
-		DBA::escape(NETWORK_DFRN),
-		DBA::escape(NETWORK_DIASPORA),
-		DBA::escape(NETWORK_OSTATUS),
+		DBA::escape(Protocol::DFRN),
+		DBA::escape(Protocol::DIASPORA),
+		DBA::escape(Protocol::OSTATUS),
 		intval($a->pager['start']),
 		intval($a->pager['itemspage'])
 	);
diff --git a/src/Content/ContactSelector.php b/src/Content/ContactSelector.php
index 07eeda423..d5efecb80 100644
--- a/src/Content/ContactSelector.php
+++ b/src/Content/ContactSelector.php
@@ -6,6 +6,7 @@ namespace Friendica\Content;
 
 use Friendica\Core\Addon;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 
 /**
@@ -74,21 +75,21 @@ class ContactSelector
 	public static function networkToName($s, $profile = "")
 	{
 		$nets = [
-			NETWORK_DFRN     => L10n::t('Friendica'),
-			NETWORK_OSTATUS  => L10n::t('OStatus'),
-			NETWORK_FEED     => L10n::t('RSS/Atom'),
-			NETWORK_MAIL     => L10n::t('Email'),
-			NETWORK_DIASPORA => L10n::t('Diaspora'),
-			NETWORK_ZOT      => L10n::t('Zot!'),
-			NETWORK_LINKEDIN => L10n::t('LinkedIn'),
-			NETWORK_XMPP     => L10n::t('XMPP/IM'),
-			NETWORK_MYSPACE  => L10n::t('MySpace'),
-			NETWORK_GPLUS    => L10n::t('Google+'),
-			NETWORK_PUMPIO   => L10n::t('pump.io'),
-			NETWORK_TWITTER  => L10n::t('Twitter'),
-			NETWORK_DIASPORA2 => L10n::t('Diaspora Connector'),
-			NETWORK_STATUSNET => L10n::t('GNU Social Connector'),
-			NETWORK_PNUT      => L10n::t('pnut')
+			Protocol::DFRN      => L10n::t('Friendica'),
+			Protocol::OSTATUS   => L10n::t('OStatus'),
+			Protocol::FEED      => L10n::t('RSS/Atom'),
+			Protocol::MAIL      => L10n::t('Email'),
+			Protocol::DIASPORA  => L10n::t('Diaspora'),
+			Protocol::ZOT       => L10n::t('Zot!'),
+			Protocol::LINKEDIN  => L10n::t('LinkedIn'),
+			Protocol::XMPP      => L10n::t('XMPP/IM'),
+			Protocol::MYSPACE   => L10n::t('MySpace'),
+			Protocol::GPLUS     => L10n::t('Google+'),
+			Protocol::PUMPIO    => L10n::t('pump.io'),
+			Protocol::TWITTER   => L10n::t('Twitter'),
+			Protocol::DIASPORA2 => L10n::t('Diaspora Connector'),
+			Protocol::STATUSNET => L10n::t('GNU Social Connector'),
+			Protocol::PNUT      => L10n::t('pnut'),
 		];
 
 		Addon::callHooks('network_to_name', $nets);
@@ -98,7 +99,7 @@ class ContactSelector
 
 		$networkname = str_replace($search, $replace, $s);
 
-		if ((in_array($s, [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])) && ($profile != "")) {
+		if ((in_array($s, [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])) && ($profile != "")) {
 			$r = DBA::fetchFirst("SELECT `gserver`.`platform` FROM `gcontact`
 					INNER JOIN `gserver` ON `gserver`.`nurl` = `gcontact`.`server_url`
 					WHERE `gcontact`.`nurl` = ? AND `platform` != ''", normalise_link($profile));
diff --git a/src/Content/Widget.php b/src/Content/Widget.php
index a46ccc62e..9662e9271 100644
--- a/src/Content/Widget.php
+++ b/src/Content/Widget.php
@@ -10,6 +10,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -83,27 +84,27 @@ class Widget
 		$networks = ['face', 'apdn'];
 
 		if (!Addon::isEnabled("statusnet")) {
-			$networks[] = NETWORK_STATUSNET;
+			$networks[] = Protocol::STATUSNET;
 		}
 
 		if (!Addon::isEnabled("pumpio")) {
-			$networks[] = NETWORK_PUMPIO;
+			$networks[] = Protocol::PUMPIO;
 		}
 
 		if (!Addon::isEnabled("twitter")) {
-			$networks[] = NETWORK_TWITTER;
+			$networks[] = Protocol::TWITTER;
 		}
 
 		if (Config::get("system", "ostatus_disabled")) {
-			$networks[] = NETWORK_OSTATUS;
+			$networks[] = Protocol::OSTATUS;
 		}
 
 		if (!Config::get("system", "diaspora_enabled")) {
-			$networks[] = NETWORK_DIASPORA;
+			$networks[] = Protocol::DIASPORA;
 		}
 
 		if (!Addon::isEnabled("pnut")) {
-			$networks[] = NETWORK_PNUT;
+			$networks[] = Protocol::PNUT;
 		}
 
 		if (!sizeof($networks)) {
diff --git a/src/Core/ACL.php b/src/Core/ACL.php
index 11af99af6..0b996bfe9 100644
--- a/src/Core/ACL.php
+++ b/src/Core/ACL.php
@@ -8,6 +8,7 @@ namespace Friendica\Core;
 
 use Friendica\BaseObject;
 use Friendica\Content\Feature;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\GContact;
@@ -46,18 +47,21 @@ class ACL extends BaseObject
 
 		switch (defaults($options, 'networks', Protocol::PHANTOM)) {
 			case 'DFRN_ONLY':
-				$networks = [NETWORK_DFRN];
+				$networks = [Protocol::DFRN];
 				break;
+
 			case 'PRIVATE':
-				$networks = [NETWORK_DFRN, NETWORK_MAIL, NETWORK_DIASPORA];
+				$networks = [Protocol::DFRN, Protocol::MAIL, Protocol::DIASPORA];
 				break;
+
 			case 'TWO_WAY':
 				if (!empty($a->user['prvnets'])) {
-					$networks = [NETWORK_DFRN, NETWORK_MAIL, NETWORK_DIASPORA];
+					$networks = [Protocol::DFRN, Protocol::MAIL, Protocol::DIASPORA];
 				} else {
-					$networks = [NETWORK_DFRN, NETWORK_MAIL, NETWORK_DIASPORA, NETWORK_OSTATUS];
+					$networks = [Protocol::DFRN, Protocol::MAIL, Protocol::DIASPORA, Protocol::OSTATUS];
 				}
 				break;
+
 			default: /// @TODO Maybe log this call?
 				break;
 		}
@@ -148,7 +152,7 @@ class ACL extends BaseObject
 		// When used for private messages, we limit correspondence to mutual DFRN/Friendica friends and the selector
 		// to one recipient. By default our selector allows multiple selects amongst all contacts.
 		$sql_extra = sprintf(" AND `rel` = %d ", intval(Contact::FRIEND));
-		$sql_extra .= sprintf(" AND `network` IN ('%s' , '%s') ", NETWORK_DFRN, NETWORK_DIASPORA);
+		$sql_extra .= sprintf(" AND `network` IN ('%s' , '%s') ", Protocol::DFRN, Protocol::DIASPORA);
 
 		$tabindex_attr = !empty($tabindex) ? ' tabindex="' . intval($tabindex) . '"' : '';
 
diff --git a/src/Core/NotificationsManager.php b/src/Core/NotificationsManager.php
index 55effc14a..734e4eb03 100644
--- a/src/Core/NotificationsManager.php
+++ b/src/Core/NotificationsManager.php
@@ -9,6 +9,7 @@ namespace Friendica\Core;
 use Friendica\BaseObject;
 use Friendica\Content\Text\BBCode;
 use Friendica\Content\Text\HTML;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Item;
@@ -235,7 +236,7 @@ class NotificationsManager extends BaseObject
 				}
 
 				// For feed items we use the user's contact, since the avatar is mostly self choosen.
-				if (!empty($it['network']) && $it['network'] == NETWORK_FEED) {
+				if (!empty($it['network']) && $it['network'] == Protocol::FEED) {
 					$it['author-avatar'] = $it['contact-avatar'];
 				}
 
@@ -639,14 +640,14 @@ class NotificationsManager extends BaseObject
 				$it = $this->getMissingIntroData($it);
 
 				// Don't show these data until you are connected. Diaspora is doing the same.
-				if ($it['gnetwork'] === NETWORK_DIASPORA) {
+				if ($it['gnetwork'] === Protocol::DIASPORA) {
 					$it['glocation'] = "";
 					$it['gabout'] = "";
 					$it['ggender'] = "";
 				}
 				$intro = [
-					'label' => (($it['network'] !== NETWORK_OSTATUS) ? 'friend_request' : 'follower'),
-					'notify_type' => (($it['network'] !== NETWORK_OSTATUS) ? L10n::t('Friend/Connect Request') : L10n::t('New Follower')),
+					'label' => (($it['network'] !== Protocol::OSTATUS) ? 'friend_request' : 'follower'),
+					'notify_type' => (($it['network'] !== Protocol::OSTATUS) ? L10n::t('Friend/Connect Request') : L10n::t('New Follower')),
 					'dfrn_id' => $it['issued-id'],
 					'uid' => $_SESSION['uid'],
 					'intro_id' => $it['intro_id'],
diff --git a/src/Core/UserImport.php b/src/Core/UserImport.php
index efd4bd2f8..e62084049 100644
--- a/src/Core/UserImport.php
+++ b/src/Core/UserImport.php
@@ -5,6 +5,7 @@
 namespace Friendica\Core;
 
 use Friendica\App;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Photo;
 use Friendica\Object\Image;
@@ -182,12 +183,12 @@ class UserImport
 				$contact["avatar-date"] = NULL_DATE;
 
 				switch ($contact['network']) {
-					case NETWORK_DFRN:
-					case NETWORK_DIASPORA:
+					case Protocol::DFRN:
+					case Protocol::DIASPORA:
 						//  send relocate message (below)
 						break;
-					case NETWORK_FEED:
-					case NETWORK_MAIL:
+					case Protocol::FEED:
+					case Protocol::MAIL:
 						// Nothing to do
 						break;
 					default:
diff --git a/src/Database/PostUpdate.php b/src/Database/PostUpdate.php
index b7c69668e..09e940b14 100644
--- a/src/Database/PostUpdate.php
+++ b/src/Database/PostUpdate.php
@@ -5,6 +5,7 @@
 namespace Friendica\Database;
 
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Model\Contact;
 use Friendica\Model\Item;
 use Friendica\Model\ItemURI;
@@ -81,7 +82,7 @@ class PostUpdate
 
 		$r = q($query1.$query2.$query3."  ORDER BY `item`.`id` LIMIT 1",
 			intval($start_id), intval($end_id),
-			DBA::escape(NETWORK_DFRN), DBA::escape(NETWORK_DIASPORA), DBA::escape(NETWORK_OSTATUS));
+			DBA::escape(Protocol::DFRN), DBA::escape(Protocol::DIASPORA), DBA::escape(Protocol::OSTATUS));
 		if (!$r) {
 			Config::set("system", "post_update_version", 1194);
 			logger("Update is done", LOGGER_DEBUG);
@@ -95,7 +96,7 @@ class PostUpdate
 
 		$r = q($query1.$query2.$query3."  ORDER BY `item`.`id` LIMIT 1000,1",
 			intval($start_id), intval($end_id),
-			DBA::escape(NETWORK_DFRN), DBA::escape(NETWORK_DIASPORA), DBA::escape(NETWORK_OSTATUS));
+			DBA::escape(Protocol::DFRN), DBA::escape(Protocol::DIASPORA), DBA::escape(Protocol::OSTATUS));
 		if ($r) {
 			$pos_id = $r[0]["id"];
 		} else {
@@ -105,7 +106,7 @@ class PostUpdate
 
 		q("UPDATE `item` ".$query2." SET `item`.`global` = 1 ".$query3,
 			intval($start_id), intval($pos_id),
-			DBA::escape(NETWORK_DFRN), DBA::escape(NETWORK_DIASPORA), DBA::escape(NETWORK_OSTATUS));
+			DBA::escape(Protocol::DFRN), DBA::escape(Protocol::DIASPORA), DBA::escape(Protocol::OSTATUS));
 
 		logger("Done", LOGGER_DEBUG);
 	}
diff --git a/src/Model/Contact.php b/src/Model/Contact.php
index 095bad37c..39a0ba718 100644
--- a/src/Model/Contact.php
+++ b/src/Model/Contact.php
@@ -9,6 +9,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -146,7 +147,7 @@ class Contact extends BaseObject
 				AND `contact`.`notify` != ""',
 				$gid,
 				local_user(),
-				NETWORK_OSTATUS
+				Protocol::OSTATUS
 			);
 			$return = $contacts['count'];
 		}
@@ -334,7 +335,7 @@ class Contact extends BaseObject
 	 */
 	public static function terminateFriendship(array $user, array $contact)
 	{
-		if (in_array($contact['network'], [NETWORK_OSTATUS, NETWORK_DFRN])) {
+		if (in_array($contact['network'], [Protocol::OSTATUS, Protocol::DFRN])) {
 			// create an unfollow slap
 			$item = [];
 			$item['verb'] = NAMESPACE_OSTATUS . "/unfollow";
@@ -349,7 +350,7 @@ class Contact extends BaseObject
 			if (!empty($contact['notify'])) {
 				Salmon::slapper($user, $contact['notify'], $slap);
 			}
-		} elseif ($contact['network'] == NETWORK_DIASPORA) {
+		} elseif ($contact['network'] == Protocol::DIASPORA) {
 			Diaspora::sendUnshare($user, $contact);
 		}
 	}
@@ -508,7 +509,7 @@ class Contact extends BaseObject
 			// If there is more than one entry we filter out the connector networks
 			if (count($r) > 1) {
 				foreach ($r as $id => $result) {
-					if ($result["network"] == NETWORK_STATUSNET) {
+					if ($result["network"] == Protocol::STATUSNET) {
 						unset($r[$id]);
 					}
 				}
@@ -562,13 +563,13 @@ class Contact extends BaseObject
 		}
 
 		if ((empty($profile["addr"]) || empty($profile["name"])) && (defaults($profile, "gid", 0) != 0)
-			&& in_array($profile["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])
+			&& in_array($profile["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])
 		) {
 			Worker::add(PRIORITY_LOW, "UpdateGContact", $profile["gid"]);
 		}
 
 		// Show contact details of Diaspora contacts only if connected
-		if ((defaults($profile, "cid", 0) == 0) && (defaults($profile, "network", "") == NETWORK_DIASPORA)) {
+		if ((defaults($profile, "cid", 0) == 0) && (defaults($profile, "network", "") == Protocol::DIASPORA)) {
 			$profile["location"] = "";
 			$profile["about"] = "";
 			$profile["gender"] = "";
@@ -687,7 +688,7 @@ class Contact extends BaseObject
 		}
 
 		$sparkle = false;
-		if (($contact['network'] === NETWORK_DFRN) && !$contact['self']) {
+		if (($contact['network'] === Protocol::DFRN) && !$contact['self']) {
 			$sparkle = true;
 			$profile_link = System::baseUrl() . '/redir/' . $contact['id'];
 		} else {
@@ -704,11 +705,11 @@ class Contact extends BaseObject
 			$profile_link = $profile_link . '?url=profile';
 		}
 
-		if (in_array($contact['network'], [NETWORK_DFRN, NETWORK_DIASPORA]) && !$contact['self']) {
+		if (in_array($contact['network'], [Protocol::DFRN, Protocol::DIASPORA]) && !$contact['self']) {
 			$pm_url = System::baseUrl() . '/message/new/' . $contact['id'];
 		}
 
-		if (($contact['network'] == NETWORK_DFRN) && !$contact['self']) {
+		if (($contact['network'] == Protocol::DFRN) && !$contact['self']) {
 			$poke_link = System::baseUrl() . '/poke/?f=&c=' . $contact['id'];
 		}
 
@@ -869,7 +870,7 @@ class Contact extends BaseObject
 		}
 
 		// Last try in gcontact for unsupported networks
-		if (!in_array($data["network"], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_DIASPORA, NETWORK_PUMPIO, NETWORK_MAIL, NETWORK_FEED])) {
+		if (!in_array($data["network"], [Protocol::DFRN, Protocol::OSTATUS, Protocol::DIASPORA, Protocol::PUMPIO, Protocol::MAIL, Protocol::FEED])) {
 			if ($uid != 0) {
 				return 0;
 			}
@@ -1108,7 +1109,7 @@ class Contact extends BaseObject
 			return '';
 		}
 
-		if (in_array($r[0]["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, ""])) {
+		if (in_array($r[0]["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, ""])) {
 			$sql = "(`item`.`uid` = 0 OR (`item`.`uid` = ? AND NOT `item`.`global`))";
 		} else {
 			$sql = "`item`.`uid` = ?";
@@ -1400,7 +1401,7 @@ class Contact extends BaseObject
 			);
 		}
 
-		if (($ret['network'] === NETWORK_DFRN) && !DBA::isResult($r)) {
+		if (($ret['network'] === Protocol::DFRN) && !DBA::isResult($r)) {
 			if ($interactive) {
 				if (strlen($a->urlpath)) {
 					$myaddr = bin2hex(System::baseUrl() . '/profile/' . $a->user['nickname']);
@@ -1412,14 +1413,14 @@ class Contact extends BaseObject
 
 				// NOTREACHED
 			}
-		} elseif (Config::get('system', 'dfrn_only') && ($ret['network'] != NETWORK_DFRN)) {
+		} elseif (Config::get('system', 'dfrn_only') && ($ret['network'] != Protocol::DFRN)) {
 			$result['message'] = L10n::t('This site is not configured to allow communications with other networks.') . EOL;
 			$result['message'] != L10n::t('No compatible communication protocols or feeds were discovered.') . EOL;
 			return $result;
 		}
 
 		// This extra param just confuses things, remove it
-		if ($ret['network'] === NETWORK_DIASPORA) {
+		if ($ret['network'] === Protocol::DIASPORA) {
 			$ret['url'] = str_replace('?absolute=true', '', $ret['url']);
 		}
 
@@ -1443,7 +1444,7 @@ class Contact extends BaseObject
 			return $result;
 		}
 
-		if ($ret['network'] === NETWORK_OSTATUS && Config::get('system', 'ostatus_disabled')) {
+		if ($ret['network'] === Protocol::OSTATUS && Config::get('system', 'ostatus_disabled')) {
 			$result['message'] .= L10n::t('The profile address specified belongs to a network which has been disabled on this site.') . EOL;
 			$ret['notify'] = '';
 		}
@@ -1452,13 +1453,13 @@ class Contact extends BaseObject
 			$result['message'] .= L10n::t('Limited profile. This person will be unable to receive direct/personal notifications from you.') . EOL;
 		}
 
-		$writeable = ((($ret['network'] === NETWORK_OSTATUS) && ($ret['notify'])) ? 1 : 0);
+		$writeable = ((($ret['network'] === Protocol::OSTATUS) && ($ret['notify'])) ? 1 : 0);
 
-		$subhub = (($ret['network'] === NETWORK_OSTATUS) ? true : false);
+		$subhub = (($ret['network'] === Protocol::OSTATUS) ? true : false);
 
-		$hidden = (($ret['network'] === NETWORK_MAIL) ? 1 : 0);
+		$hidden = (($ret['network'] === Protocol::MAIL) ? 1 : 0);
 
-		if (in_array($ret['network'], [NETWORK_MAIL, NETWORK_DIASPORA])) {
+		if (in_array($ret['network'], [Protocol::MAIL, Protocol::DIASPORA])) {
 			$writeable = 1;
 		}
 
@@ -1469,7 +1470,7 @@ class Contact extends BaseObject
 			$fields = ['rel' => $new_relation, 'subhub' => $subhub, 'readonly' => false];
 			DBA::update('contact', $fields, ['id' => $r[0]['id']]);
 		} else {
-			$new_relation = ((in_array($ret['network'], [NETWORK_MAIL])) ? self::FRIEND : self::SHARING);
+			$new_relation = ((in_array($ret['network'], [Protocol::MAIL])) ? self::FRIEND : self::SHARING);
 
 			// create contact record
 			DBA::insert('contact', [
@@ -1522,7 +1523,7 @@ class Contact extends BaseObject
 		);
 
 		if (DBA::isResult($r)) {
-			if (in_array($contact['network'], [NETWORK_OSTATUS, NETWORK_DFRN])) {
+			if (in_array($contact['network'], [Protocol::OSTATUS, Protocol::DFRN])) {
 				// create a follow slap
 				$item = [];
 				$item['verb'] = ACTIVITY_FOLLOW;
@@ -1536,7 +1537,7 @@ class Contact extends BaseObject
 				if (!empty($contact['notify'])) {
 					Salmon::slapper($r[0], $contact['notify'], $slap);
 				}
-			} elseif ($contact['network'] == NETWORK_DIASPORA) {
+			} elseif ($contact['network'] == Protocol::DIASPORA) {
 				$ret = Diaspora::sendShare($a->user, $contact);
 				logger('share returns: ' . $ret);
 			}
@@ -1817,7 +1818,7 @@ class Contact extends BaseObject
 	 */
 	public static function magicLinkbyContact($contact, $url = '')
 	{
-		if ($contact['network'] != NETWORK_DFRN) {
+		if ($contact['network'] != Protocol::DFRN) {
 			return $url ?: $contact['url']; // Equivalent to ($url != '') ? $url : $contact['url'];
 		}
 
diff --git a/src/Model/Conversation.php b/src/Model/Conversation.php
index cb32c0f20..29ec4771d 100644
--- a/src/Model/Conversation.php
+++ b/src/Model/Conversation.php
@@ -5,6 +5,7 @@
 
 namespace Friendica\Model;
 
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Util\DateTimeFormat;
 
@@ -32,8 +33,8 @@ class Conversation
 	 */
 	public static function insert(array $arr)
 	{
-		if (in_array(defaults($arr, 'network', NETWORK_PHANTOM),
-				[NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, NETWORK_TWITTER]) && !empty($arr['uri'])) {
+		if (in_array(defaults($arr, 'network', Protocol::PHANTOM),
+				[Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, Protocol::TWITTER]) && !empty($arr['uri'])) {
 			$conversation = ['item-uri' => $arr['uri'], 'received' => DateTimeFormat::utcNow()];
 
 			if (isset($arr['parent-uri']) && ($arr['parent-uri'] != $arr['uri'])) {
diff --git a/src/Model/GContact.php b/src/Model/GContact.php
index 94a2c1140..eb93c55ce 100644
--- a/src/Model/GContact.php
+++ b/src/Model/GContact.php
@@ -8,6 +8,7 @@ namespace Friendica\Model;
 
 use Exception;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -39,15 +40,15 @@ class GContact
 
 		// check supported networks
 		if (Config::get('system', 'diaspora_enabled')) {
-			$diaspora = NETWORK_DIASPORA;
+			$diaspora = Protocol::DIASPORA;
 		} else {
-			$diaspora = NETWORK_DFRN;
+			$diaspora = Protocol::DFRN;
 		}
 
 		if (!Config::get('system', 'ostatus_disabled')) {
-			$ostatus = NETWORK_OSTATUS;
+			$ostatus = Protocol::OSTATUS;
 		} else {
-			$ostatus = NETWORK_DFRN;
+			$ostatus = Protocol::DFRN;
 		}
 
 		// check if we search only communities or every contact
@@ -64,7 +65,7 @@ class GContact
 				((`last_contact` >= `last_failure`) OR (`updated` >= `last_failure`)) AND
 				(`addr` LIKE ? OR `name` LIKE ? OR `nick` LIKE ?) $extra_sql
 				GROUP BY `nurl` ORDER BY `nurl` DESC LIMIT 1000",
-			NETWORK_DFRN, $ostatus, $diaspora, $search, $search, $search
+			Protocol::DFRN, $ostatus, $diaspora, $search, $search, $search
 		);
 
 		$gcontacts = [];
@@ -156,13 +157,13 @@ class GContact
 		}
 
 		// Don't store the statusnet connector as network
-		// We can't simply set this to NETWORK_OSTATUS since the connector could have fetched posts from friendica as well
-		if ($gcontact['network'] == NETWORK_STATUSNET) {
+		// We can't simply set this to Protocol::OSTATUS since the connector could have fetched posts from friendica as well
+		if ($gcontact['network'] == Protocol::STATUSNET) {
 			$gcontact['network'] = "";
 		}
 
 		// Assure that there are no parameter fragments in the profile url
-		if (in_array($gcontact['network'], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, ""])) {
+		if (in_array($gcontact['network'], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, ""])) {
 			$gcontact['url'] = self::cleanContactUrl($gcontact['url']);
 		}
 
@@ -177,18 +178,18 @@ class GContact
 			$r = q(
 				"SELECT `network` FROM `contact` WHERE `uid` = 0 AND `nurl` = '%s' AND `network` != '' AND `network` != '%s' LIMIT 1",
 				DBA::escape(normalise_link($gcontact['url'])),
-				DBA::escape(NETWORK_STATUSNET)
+				DBA::escape(Protocol::STATUSNET)
 			);
 			if (DBA::isResult($r)) {
 				$gcontact['network'] = $r[0]["network"];
 			}
 
-			if (($gcontact['network'] == "") || ($gcontact['network'] == NETWORK_OSTATUS)) {
+			if (($gcontact['network'] == "") || ($gcontact['network'] == Protocol::OSTATUS)) {
 				$r = q(
 					"SELECT `network`, `url` FROM `contact` WHERE `uid` = 0 AND `alias` IN ('%s', '%s') AND `network` != '' AND `network` != '%s' LIMIT 1",
 					DBA::escape($gcontact['url']),
 					DBA::escape(normalise_link($gcontact['url'])),
-					DBA::escape(NETWORK_STATUSNET)
+					DBA::escape(Protocol::STATUSNET)
 				);
 				if (DBA::isResult($r)) {
 					$gcontact['network'] = $r[0]["network"];
@@ -205,7 +206,7 @@ class GContact
 		);
 
 		if (DBA::isResult($x)) {
-			if (!isset($gcontact['network']) && ($x[0]["network"] != NETWORK_STATUSNET)) {
+			if (!isset($gcontact['network']) && ($x[0]["network"] != Protocol::STATUSNET)) {
 				$gcontact['network'] = $x[0]["network"];
 			}
 			if ($gcontact['updated'] <= NULL_DATE) {
@@ -224,7 +225,7 @@ class GContact
 		) {
 			$data = Probe::uri($gcontact['url']);
 
-			if ($data["network"] == NETWORK_PHANTOM) {
+			if ($data["network"] == Protocol::PHANTOM) {
 				throw new Exception('Probing for URL '.$gcontact['url'].' failed');
 			}
 
@@ -234,7 +235,7 @@ class GContact
 
 			$gcontact = array_merge($gcontact, $data);
 
-			if ($alternate && ($gcontact['network'] == NETWORK_OSTATUS)) {
+			if ($alternate && ($gcontact['network'] == Protocol::OSTATUS)) {
 				// Delete the old entry - if it exists
 				if (DBA::exists('gcontact', ['nurl' => normalise_link($orig_profile)])) {
 					DBA::delete('gcontact', ['nurl' => normalise_link($orig_profile)]);
@@ -246,7 +247,7 @@ class GContact
 			throw new Exception('No name and photo for URL '.$gcontact['url']);
 		}
 
-		if (!in_array($gcontact['network'], [NETWORK_DFRN, NETWORK_OSTATUS, NETWORK_DIASPORA])) {
+		if (!in_array($gcontact['network'], [Protocol::DFRN, Protocol::OSTATUS, Protocol::DIASPORA])) {
 			throw new Exception('No federated network ('.$gcontact['network'].') detected for URL '.$gcontact['url']);
 		}
 
@@ -460,14 +461,14 @@ class GContact
 		//	return $list;
 		//}
 
-		$network = [NETWORK_DFRN];
+		$network = [Protocol::DFRN];
 
 		if (Config::get('system', 'diaspora_enabled')) {
-			$network[] = NETWORK_DIASPORA;
+			$network[] = Protocol::DIASPORA;
 		}
 
 		if (!Config::get('system', 'ostatus_disabled')) {
-			$network[] = NETWORK_OSTATUS;
+			$network[] = Protocol::OSTATUS;
 		}
 
 		$sql_network = implode("', '", $network);
@@ -580,8 +581,8 @@ class GContact
 		// Query your contacts from Friendica and Redmatrix/Hubzilla for their contacts
 		$r = q(
 			"SELECT DISTINCT(`poco`) AS `poco` FROM `contact` WHERE `network` IN ('%s', '%s')",
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA)
 		);
 
 		if (DBA::isResult($r)) {
@@ -634,9 +635,9 @@ class GContact
 	 */
 	public static function fixAlternateContactAddress(&$contact)
 	{
-		if (($contact["network"] == NETWORK_OSTATUS) && PortableContact::alternateOStatusUrl($contact["url"])) {
+		if (($contact["network"] == Protocol::OSTATUS) && PortableContact::alternateOStatusUrl($contact["url"])) {
 			$data = Probe::uri($contact["url"]);
-			if ($contact["network"] == NETWORK_OSTATUS) {
+			if ($contact["network"] == Protocol::OSTATUS) {
 				logger("Fix primary url from ".$contact["url"]." to ".$data["url"]." - Called by: ".System::callstack(), LOGGER_DEBUG);
 				$contact["url"] = $data["url"];
 				$contact["addr"] = $data["addr"];
@@ -665,13 +666,13 @@ class GContact
 			return false;
 		}
 
-		if (in_array($contact["network"], [NETWORK_PHANTOM])) {
+		if (in_array($contact["network"], [Protocol::PHANTOM])) {
 			logger("Invalid network for contact url ".$contact["url"]." - Called by: ".System::callstack(), LOGGER_DEBUG);
 			return false;
 		}
 
-		if ($contact["network"] == NETWORK_STATUSNET) {
-			$contact["network"] = NETWORK_OSTATUS;
+		if ($contact["network"] == Protocol::STATUSNET) {
+			$contact["network"] = Protocol::OSTATUS;
 		}
 
 		// All new contacts are hidden by default
@@ -683,7 +684,7 @@ class GContact
 		self::fixAlternateContactAddress($contact);
 
 		// Remove unwanted parts from the contact url (e.g. "?zrl=...")
-		if (in_array($contact["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])) {
+		if (in_array($contact["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])) {
 			$contact["url"] = self::cleanContactUrl($contact["url"]);
 		}
 
@@ -697,7 +698,7 @@ class GContact
 			$gcontact_id = $r[0]["id"];
 
 			// Update every 90 days
-			if (in_array($r[0]["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, ""])) {
+			if (in_array($r[0]["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, ""])) {
 				$last_failure_str = $r[0]["last_failure"];
 				$last_failure = strtotime($r[0]["last_failure"]);
 				$last_contact_str = $r[0]["last_contact"];
@@ -735,7 +736,7 @@ class GContact
 			if (DBA::isResult($r)) {
 				$gcontact_id = $r[0]["id"];
 
-				$doprobing = in_array($r[0]["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, ""]);
+				$doprobing = in_array($r[0]["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, ""]);
 			}
 		}
 		DBA::unlock();
@@ -810,8 +811,8 @@ class GContact
 
 		$fields["hide"] = $public_contact[0]["hide"];
 
-		if ($contact["network"] == NETWORK_STATUSNET) {
-			$contact["network"] = NETWORK_OSTATUS;
+		if ($contact["network"] == Protocol::STATUSNET) {
+			$contact["network"] = Protocol::OSTATUS;
 		}
 
 		// Replace alternate OStatus user format with the primary one
@@ -821,13 +822,13 @@ class GContact
 			$contact["updated"] = DateTimeFormat::utcNow();
 		}
 
-		if ($contact["network"] == NETWORK_TWITTER) {
+		if ($contact["network"] == Protocol::TWITTER) {
 			$contact["server_url"] = 'http://twitter.com';
 		}
 
 		if ($contact["server_url"] == "") {
 			$data = Probe::uri($contact["url"]);
-			if ($data["network"] != NETWORK_PHANTOM) {
+			if ($data["network"] != Protocol::PHANTOM) {
 				$contact["server_url"] = $data['baseurl'];
 			}
 		} else {
@@ -923,7 +924,7 @@ class GContact
 	{
 		$data = Probe::uri($url);
 
-		if (in_array($data["network"], [NETWORK_PHANTOM])) {
+		if (in_array($data["network"], [Protocol::PHANTOM])) {
 			logger("Invalid network for contact url ".$data["url"]." - Called by: ".System::callstack(), LOGGER_DEBUG);
 			return;
 		}
@@ -972,7 +973,7 @@ class GContact
 				"hide" => ($r[0]["hidewall"] || !$r[0]["net-publish"]),
 				"nick" => $r[0]["nickname"], "addr" => $addr,
 				"connect" => $addr, "server_url" => System::baseUrl(),
-				"generation" => 1, "network" => NETWORK_DFRN];
+				"generation" => 1, "network" => Protocol::DFRN];
 
 		self::update($gcontact);
 	}
@@ -1028,7 +1029,7 @@ class GContact
 						"name" => $user->fullname,
 						"addr" => $user->nickname."@".$hostname,
 						"nick" => $user->nickname,
-						"network" => NETWORK_OSTATUS,
+						"network" => Protocol::OSTATUS,
 						"photo" => System::baseUrl()."/images/person-175.jpg"];
 
 				if (isset($user->bio)) {
@@ -1052,7 +1053,7 @@ class GContact
 
 		$r = q(
 			"SELECT `nurl`, `url` FROM `gserver` WHERE `last_contact` >= `last_failure` AND `network` = '%s' AND `last_poco_query` < '%s' ORDER BY RAND() LIMIT 5",
-			DBA::escape(NETWORK_OSTATUS),
+			DBA::escape(Protocol::OSTATUS),
 			DBA::escape($last_update)
 		);
 
@@ -1076,7 +1077,7 @@ class GContact
 					AND `last_contact` >= `last_failure`
 					AND `updated` > UTC_TIMESTAMP - INTERVAL 1 MONTH
 				ORDER BY rand() LIMIT 1",
-			DBA::escape(NETWORK_DFRN)
+			DBA::escape(Protocol::DFRN)
 		);
 
 		if (DBA::isResult($r)) {
diff --git a/src/Model/Item.php b/src/Model/Item.php
index 3b491cbe8..e22af0e26 100644
--- a/src/Model/Item.php
+++ b/src/Model/Item.php
@@ -12,6 +12,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\Lock;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -175,7 +176,7 @@ class Item extends BaseObject
 
 		// We can always comment on posts from these networks
 		if (array_key_exists('writable', $row) &&
-			in_array($row['internal-network'], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])) {
+			in_array($row['internal-network'], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])) {
 			$row['writable'] = true;
 		}
 
@@ -1254,7 +1255,7 @@ class Item extends BaseObject
 		if ($notify) {
 			$item['wall'] = 1;
 			$item['origin'] = 1;
-			$item['network'] = NETWORK_DFRN;
+			$item['network'] = Protocol::DFRN;
 			$item['protocol'] = Conversation::PARCEL_DFRN;
 
 			if (is_int($notify)) {
@@ -1263,7 +1264,7 @@ class Item extends BaseObject
 				$priority = PRIORITY_HIGH;
 			}
 		} else {
-			$item['network'] = trim(defaults($item, 'network', NETWORK_PHANTOM));
+			$item['network'] = trim(defaults($item, 'network', Protocol::PHANTOM));
 		}
 
 		$item['guid'] = self::guid($item, $notify);
@@ -1296,7 +1297,7 @@ class Item extends BaseObject
 
 		// Converting the plink
 		/// @TODO Check if this is really still needed
-		if ($item['network'] == NETWORK_OSTATUS) {
+		if ($item['network'] == Protocol::OSTATUS) {
 			if (isset($item['plink'])) {
 				$item['plink'] = OStatus::convertHref($item['plink']);
 			} elseif (isset($item['uri'])) {
@@ -1343,10 +1344,10 @@ class Item extends BaseObject
 		 * We have to check several networks since Friendica posts could be repeated
 		 * via OStatus (maybe Diasporsa as well)
 		 */
-		if (in_array($item['network'], [NETWORK_DIASPORA, NETWORK_DFRN, NETWORK_OSTATUS, ""])) {
+		if (in_array($item['network'], [Protocol::DIASPORA, Protocol::DFRN, Protocol::OSTATUS, ""])) {
 			$condition = ["`uri` = ? AND `uid` = ? AND `network` IN (?, ?, ?)",
 				trim($item['uri']), $item['uid'],
-				NETWORK_DIASPORA, NETWORK_DFRN, NETWORK_OSTATUS];
+				Protocol::DIASPORA, Protocol::DFRN, Protocol::OSTATUS];
 			$existing = self::selectFirst(['id', 'network'], $condition);
 			if (DBA::isResult($existing)) {
 				// We only log the entries with a different user id than 0. Otherwise we would have too many false positives
@@ -1462,10 +1463,10 @@ class Item extends BaseObject
 		unset($item['owner-name']);
 		unset($item['owner-avatar']);
 
-		if ($item['network'] == NETWORK_PHANTOM) {
+		if ($item['network'] == Protocol::PHANTOM) {
 			logger('Missing network. Called by: '.System::callstack(), LOGGER_DEBUG);
 
-			$item['network'] = NETWORK_DFRN;
+			$item['network'] = Protocol::DFRN;
 			logger("Set network to " . $item["network"] . " for " . $item["uri"], LOGGER_DEBUG);
 		}
 
@@ -1588,14 +1589,14 @@ class Item extends BaseObject
 		$item['thr-parent-id'] = ItemURI::getIdByURI($item['thr-parent']);
 
 		$condition = ["`uri` = ? AND `network` IN (?, ?) AND `uid` = ?",
-			$item['uri'], $item['network'], NETWORK_DFRN, $item['uid']];
+			$item['uri'], $item['network'], Protocol::DFRN, $item['uid']];
 		if (self::exists($condition)) {
 			logger('duplicated item with the same uri found. '.print_r($item,true));
 			return 0;
 		}
 
 		// On Friendica and Diaspora the GUID is unique
-		if (in_array($item['network'], [NETWORK_DFRN, NETWORK_DIASPORA])) {
+		if (in_array($item['network'], [Protocol::DFRN, Protocol::DIASPORA])) {
 			$condition = ['guid' => $item['guid'], 'uid' => $item['uid']];
 			if (self::exists($condition)) {
 				logger('duplicated item with the same guid found. '.print_r($item,true));
@@ -2044,7 +2045,7 @@ class Item extends BaseObject
 
 		// Only distribute public items from native networks
 		$condition = ['id' => $itemid, 'uid' => 0,
-			'network' => [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, ""],
+			'network' => [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, ""],
 			'visible' => true, 'deleted' => false, 'moderated' => false, 'private' => false];
 		$item = self::selectFirst(self::ITEM_FIELDLIST, ['id' => $itemid]);
 		if (!DBA::isResult($item)) {
@@ -2166,7 +2167,7 @@ class Item extends BaseObject
 		}
 
 		// is it an entry from a connector? Only add an entry for natively connected networks
-		if (!in_array($item["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, ""])) {
+		if (!in_array($item["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, ""])) {
 			return;
 		}
 
@@ -2256,7 +2257,7 @@ class Item extends BaseObject
 
 		// If this was a comment to a Diaspora post we don't get our comment back.
 		// This means that we have to distribute the comment by ourselves.
-		if ($origin && self::exists(['id' => $parent, 'network' => NETWORK_DIASPORA])) {
+		if ($origin && self::exists(['id' => $parent, 'network' => Protocol::DIASPORA])) {
 			self::distribute($public_shadow);
 		}
 	}
@@ -2355,7 +2356,7 @@ class Item extends BaseObject
 		$update = (!$arr['private'] && ((defaults($arr, 'author-link', '') === defaults($arr, 'owner-link', '')) || ($arr["parent-uri"] === $arr["uri"])));
 
 		// Is it a forum? Then we don't care about the rules from above
-		if (!$update && ($arr["network"] == NETWORK_DFRN) && ($arr["parent-uri"] === $arr["uri"])) {
+		if (!$update && ($arr["network"] == Protocol::DFRN) && ($arr["parent-uri"] === $arr["uri"])) {
 			if (DBA::exists('contact', ['id' => $arr['contact-id'], 'forum' => true])) {
 				$update = true;
 			}
@@ -2594,7 +2595,7 @@ class Item extends BaseObject
 		}
 
 		// Prevent the forwarding of posts that are forwarded
-		if (!empty($datarray["extid"]) && ($datarray["extid"] == NETWORK_DFRN)) {
+		if (!empty($datarray["extid"]) && ($datarray["extid"] == Protocol::DFRN)) {
 			logger('Already forwarded', LOGGER_DEBUG);
 			return false;
 		}
@@ -2611,7 +2612,7 @@ class Item extends BaseObject
 			return false;
 		}
 
-		if (($contact['network'] != NETWORK_FEED) && $datarray['private']) {
+		if (($contact['network'] != Protocol::FEED) && $datarray['private']) {
 			logger('Not public', LOGGER_DEBUG);
 			return false;
 		}
@@ -2640,13 +2641,13 @@ class Item extends BaseObject
 				unset($datarray['author-id']);
 			}
 
-			if ($contact['network'] != NETWORK_FEED) {
+			if ($contact['network'] != Protocol::FEED) {
 				$datarray["guid"] = System::createGUID(32);
 				unset($datarray["plink"]);
 				$datarray["uri"] = self::newURI($contact['uid'], $datarray["guid"]);
 				$datarray["parent-uri"] = $datarray["uri"];
 				$datarray["thr-parent"] = $datarray["uri"];
-				$datarray["extid"] = NETWORK_DFRN;
+				$datarray["extid"] = Protocol::DFRN;
 				$urlpart = parse_url($datarray2['author-link']);
 				$datarray["app"] = $urlpart["host"];
 			} else {
@@ -2654,7 +2655,7 @@ class Item extends BaseObject
 			}
 		}
 
-		if ($contact['network'] != NETWORK_FEED) {
+		if ($contact['network'] != Protocol::FEED) {
 			// Store the original post
 			$result = self::insert($datarray2, false, false);
 			logger('remote-self post original item - Contact '.$contact['url'].' return '.$result.' Item '.print_r($datarray2, true), LOGGER_DEBUG);
@@ -3076,7 +3077,7 @@ class Item extends BaseObject
 			'contact-id'    => $item_contact_id,
 			'wall'          => $item['wall'],
 			'origin'        => 1,
-			'network'       => NETWORK_DFRN,
+			'network'       => Protocol::DFRN,
 			'gravity'       => GRAVITY_ACTIVITY,
 			'parent'        => $item['id'],
 			'parent-uri'    => $item['uri'],
diff --git a/src/Model/ItemContent.php b/src/Model/ItemContent.php
index 250400ef4..c51f471d8 100644
--- a/src/Model/ItemContent.php
+++ b/src/Model/ItemContent.php
@@ -9,6 +9,7 @@ namespace Friendica\Model;
 use Friendica\BaseObject;
 use Friendica\Content\Text;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 
 require_once 'boot.php';
 require_once 'include/items.php';
@@ -68,11 +69,13 @@ class ItemContent extends BaseObject
 		} else {// Try to guess the correct target network
 			switch ($htmlmode) {
 				case 8:
-					$abstract = Text\BBCode::getAbstract($item['body'], NETWORK_TWITTER);
+					$abstract = Text\BBCode::getAbstract($item['body'], Protocol::TWITTER);
 					break;
+
 				case 7:
-					$abstract = Text\BBCode::getAbstract($item['body'], NETWORK_STATUSNET);
+					$abstract = Text\BBCode::getAbstract($item['body'], Protocol::STATUSNET);
 					break;
+
 				default: // We don't know the exact target.
 					// We fetch an abstract since there is a posting limit.
 					if ($limit > 0) {
diff --git a/src/Model/Profile.php b/src/Model/Profile.php
index 0f99379bc..b6400a596 100644
--- a/src/Model/Profile.php
+++ b/src/Model/Profile.php
@@ -13,6 +13,7 @@ use Friendica\Core\Cache;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -136,7 +137,7 @@ class Profile
 		$a->profile_uid = $pdata['profile_uid'];
 
 		$a->profile['mobile-theme'] = PConfig::get($a->profile['profile_uid'], 'system', 'mobile_theme');
-		$a->profile['network'] = NETWORK_DFRN;
+		$a->profile['network'] = Protocol::DFRN;
 
 		$a->page['title'] = $a->profile['name'] . ' @ ' . Config::get('config', 'sitename');
 
@@ -280,7 +281,7 @@ class Profile
 
 		$profile['picdate'] = urlencode(defaults($profile, 'picdate', ''));
 
-		if (($profile['network'] != '') && ($profile['network'] != NETWORK_DFRN)) {
+		if (($profile['network'] != '') && ($profile['network'] != Protocol::DFRN)) {
 			$profile['network_name'] = format_network_name($profile['network'], $profile['url']);
 		} else {
 			$profile['network_name'] = '';
@@ -321,7 +322,7 @@ class Profile
 			}
 		}
 
-		if ($connect && ($profile['network'] != NETWORK_DFRN) && !isset($profile['remoteconnect'])) {
+		if ($connect && ($profile['network'] != Protocol::DFRN) && !isset($profile['remoteconnect'])) {
 			$connect = false;
 		}
 
@@ -330,7 +331,7 @@ class Profile
 			$remoteconnect = $profile['remoteconnect'];
 		}
 
-		if ($connect && ($profile['network'] == NETWORK_DFRN) && !isset($remoteconnect)) {
+		if ($connect && ($profile['network'] == Protocol::DFRN) && !isset($remoteconnect)) {
 			$subscribe_feed = L10n::t('Atom feed');
 		} else {
 			$subscribe_feed = false;
@@ -471,9 +472,9 @@ class Profile
 						AND NOT `hidden` AND NOT `archive`
 						AND `network` IN ('%s', '%s', '%s', '')",
 					intval($profile['uid']),
-					DBA::escape(NETWORK_DFRN),
-					DBA::escape(NETWORK_DIASPORA),
-					DBA::escape(NETWORK_OSTATUS)
+					DBA::escape(Protocol::DFRN),
+					DBA::escape(Protocol::DIASPORA),
+					DBA::escape(Protocol::OSTATUS)
 				);
 				if (DBA::isResult($r)) {
 					$contacts = intval($r[0]['total']);
@@ -1016,7 +1017,7 @@ class Profile
 				$urlparts = parse_url($my_url);
 
 				$result = Cache::get('gprobe:' . $urlparts['host']);
-				if ((!is_null($result)) && (in_array($result['network'], [NETWORK_FEED, NETWORK_PHANTOM]))) {
+				if ((!is_null($result)) && (in_array($result['network'], [Protocol::FEED, Protocol::PHANTOM]))) {
 					logger('DDoS attempt detected for ' . $urlparts['host'] . ' by ' . $_SERVER['REMOTE_ADDR'] . '. server data: ' . print_r($_SERVER, true), LOGGER_DEBUG);
 					return;
 				}
diff --git a/src/Model/User.php b/src/Model/User.php
index 96f207c4a..46ffc1384 100644
--- a/src/Model/User.php
+++ b/src/Model/User.php
@@ -11,6 +11,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -88,7 +89,7 @@ class User
 	{
 		$default_group = 0;
 
-		if ($network == NETWORK_OSTATUS) {
+		if ($network == Protocol::OSTATUS) {
 			$default_group = PConfig::get($uid, "ostatus", "default_group");
 		}
 
diff --git a/src/Network/Probe.php b/src/Network/Probe.php
index 75312fee9..49c27fb4f 100644
--- a/src/Network/Probe.php
+++ b/src/Network/Probe.php
@@ -12,6 +12,7 @@ namespace Friendica\Network;
 use DOMDocument;
 use Friendica\Core\Cache;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -362,20 +363,20 @@ class Probe
 		}
 
 		if (empty($data["network"])) {
-			$data["network"] = NETWORK_PHANTOM;
+			$data["network"] = Protocol::PHANTOM;
 		}
 
 		$data = self::rearrangeData($data);
 
 		// Only store into the cache if the value seems to be valid
-		if (!in_array($data['network'], [NETWORK_PHANTOM, NETWORK_MAIL])) {
+		if (!in_array($data['network'], [Protocol::PHANTOM, Protocol::MAIL])) {
 			Cache::set("Probe::uri:".$network.":".$uri, $data, CACHE_DAY);
 
 			/// @todo temporary fix - we need a real contact update function that updates only changing fields
 			/// The biggest problem is the avatar picture that could have a reduced image size.
 			/// It should only be updated if the existing picture isn't existing anymore.
 			/// We only update the contact when it is no probing for a specific network.
-			if (($data['network'] != NETWORK_FEED)
+			if (($data['network'] != Protocol::FEED)
 				&& ($network == "")
 				&& $data["name"]
 				&& $data["nick"]
@@ -568,7 +569,7 @@ class Probe
 			}
 
 			if ($host == 'twitter.com') {
-				return ["network" => NETWORK_TWITTER];
+				return ["network" => Protocol::TWITTER];
 			}
 			$lrdd = self::hostMeta($host);
 
@@ -599,7 +600,7 @@ class Probe
 				return self::mail($uri, $uid);
 			}
 
-			if ($network == NETWORK_MAIL) {
+			if ($network == Protocol::MAIL) {
 				return self::mail($uri, $uid);
 			}
 			// Remove "acct:" from the URI
@@ -609,7 +610,7 @@ class Probe
 			$nick = substr($uri, 0, strpos($uri, '@'));
 
 			if (strpos($uri, '@twitter.com')) {
-				return ["network" => NETWORK_TWITTER];
+				return ["network" => Protocol::TWITTER];
 			}
 			$lrdd = self::hostMeta($host);
 
@@ -670,19 +671,19 @@ class Probe
 
 		logger("Probing ".$uri, LOGGER_DEBUG);
 
-		if (in_array($network, ["", NETWORK_DFRN])) {
+		if (in_array($network, ["", Protocol::DFRN])) {
 			$result = self::dfrn($webfinger);
 		}
-		if ((!$result && ($network == "")) || ($network == NETWORK_DIASPORA)) {
+		if ((!$result && ($network == "")) || ($network == Protocol::DIASPORA)) {
 			$result = self::diaspora($webfinger);
 		}
-		if ((!$result && ($network == "")) || ($network == NETWORK_OSTATUS)) {
+		if ((!$result && ($network == "")) || ($network == Protocol::OSTATUS)) {
 			$result = self::ostatus($webfinger);
 		}
-		if ((!$result && ($network == "")) || ($network == NETWORK_PUMPIO)) {
+		if ((!$result && ($network == "")) || ($network == Protocol::PUMPIO)) {
 			$result = self::pumpio($webfinger, $addr);
 		}
-		if ((!$result && ($network == "")) || ($network == NETWORK_FEED)) {
+		if ((!$result && ($network == "")) || ($network == Protocol::FEED)) {
 			$result = self::feed($uri);
 		} else {
 			// We overwrite the detected nick with our try if the previois routines hadn't detected it.
@@ -697,7 +698,7 @@ class Probe
 		}
 
 		if (empty($result["network"])) {
-			$result["network"] = NETWORK_PHANTOM;
+			$result["network"] = Protocol::PHANTOM;
 		}
 
 		if (empty($result["url"])) {
@@ -960,7 +961,7 @@ class Probe
 		$data = [];
 		foreach ($webfinger["links"] as $link) {
 			if (($link["rel"] == NAMESPACE_DFRN) && ($link["href"] != "")) {
-				$data["network"] = NETWORK_DFRN;
+				$data["network"] = Protocol::DFRN;
 			} elseif (($link["rel"] == NAMESPACE_FEED) && ($link["href"] != "")) {
 				$data["poll"] = $link["href"];
 			} elseif (($link["rel"] == "http://webfinger.net/rel/profile-page") && ($link["type"] == "text/html") && ($link["href"] != "")) {
@@ -1215,7 +1216,7 @@ class Probe
 			&& isset($data["pubkey"])
 			&& ($hcard_url != "")
 		) {
-			$data["network"] = NETWORK_DIASPORA;
+			$data["network"] = Protocol::DIASPORA;
 
 			// The Diaspora handle must always be lowercase
 			if (!empty($data["addr"])) {
@@ -1302,7 +1303,7 @@ class Probe
 			&& isset($data["poll"])
 			&& isset($data["url"])
 		) {
-			$data["network"] = NETWORK_OSTATUS;
+			$data["network"] = Protocol::OSTATUS;
 		} else {
 			return false;
 		}
@@ -1446,7 +1447,7 @@ class Probe
 			// So we unset all data that isn't used at the moment
 			unset($data["dialback"]);
 
-			$data["network"] = NETWORK_PUMPIO;
+			$data["network"] = Protocol::PUMPIO;
 		} else {
 			return false;
 		}
@@ -1569,7 +1570,7 @@ class Probe
 			$data["baseurl"] = $data["url"];
 		}
 
-		$data["network"] = NETWORK_FEED;
+		$data["network"] = Protocol::FEED;
 
 		return $data;
 	}
@@ -1619,7 +1620,7 @@ class Probe
 
 		$data = [];
 		$data["addr"]    = $uri;
-		$data["network"] = NETWORK_MAIL;
+		$data["network"] = Protocol::MAIL;
 		$data["name"]    = substr($uri, 0, strpos($uri, '@'));
 		$data["nick"]    = $data["name"];
 		$data["photo"]   = Network::lookupAvatarByEmail($uri);
diff --git a/src/Object/Post.php b/src/Object/Post.php
index 05b21ebd4..038ca270d 100644
--- a/src/Object/Post.php
+++ b/src/Object/Post.php
@@ -11,6 +11,7 @@ use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Item;
@@ -84,14 +85,14 @@ class Post extends BaseObject
 		if (!empty($data['children'])) {
 			foreach ($data['children'] as $item) {
 				// Only add will be displayed
-				if ($item['network'] === NETWORK_MAIL && local_user() != $item['uid']) {
+				if ($item['network'] === Protocol::MAIL && local_user() != $item['uid']) {
 					continue;
 				} elseif (!visible_activity($item)) {
 					continue;
 				}
 
 				// You can always comment on Diaspora and OStatus items
-				if (in_array($item['network'], [NETWORK_OSTATUS, NETWORK_DIASPORA]) && (local_user() == $item['uid'])) {
+				if (in_array($item['network'], [Protocol::OSTATUS, Protocol::DIASPORA]) && (local_user() == $item['uid'])) {
 					$item['writable'] = true;
 				}
 
@@ -323,17 +324,17 @@ class Post extends BaseObject
 		$owner_name_e = $this->getOwnerName();
 
 		// Disable features that aren't available in several networks
-		if (!in_array($item["network"], [NETWORK_DFRN, NETWORK_DIASPORA]) && isset($buttons["dislike"])) {
+		if (!in_array($item["network"], [Protocol::DFRN, Protocol::DIASPORA]) && isset($buttons["dislike"])) {
 			unset($buttons["dislike"]);
 			$isevent = false;
 			$tagger = '';
 		}
 
-		if (($item["network"] == NETWORK_FEED) && isset($buttons["like"])) {
+		if (($item["network"] == Protocol::FEED) && isset($buttons["like"])) {
 			unset($buttons["like"]);
 		}
 
-		if (($item["network"] == NETWORK_MAIL) && isset($buttons["like"])) {
+		if (($item["network"] == Protocol::MAIL) && isset($buttons["like"])) {
 			unset($buttons["like"]);
 		}
 
@@ -489,7 +490,7 @@ class Post extends BaseObject
 		/*
 		 * Only add what will be displayed
 		 */
-		if ($item->getDataValue('network') === NETWORK_MAIL && local_user() != $item->getDataValue('uid')) {
+		if ($item->getDataValue('network') === Protocol::MAIL && local_user() != $item->getDataValue('uid')) {
 			return false;
 		} elseif (activity_match($item->getDataValue('verb'), ACTIVITY_LIKE) || activity_match($item->getDataValue('verb'), ACTIVITY_DISLIKE)) {
 			return false;
diff --git a/src/Object/Thread.php b/src/Object/Thread.php
index 799029a28..e396d6cbc 100644
--- a/src/Object/Thread.php
+++ b/src/Object/Thread.php
@@ -5,6 +5,7 @@
 namespace Friendica\Object;
 
 use Friendica\BaseObject;
+use Friendica\Core\Protocol;
 use Friendica\Object\Post;
 
 require_once 'boot.php';
@@ -143,7 +144,7 @@ class Thread extends BaseObject
 		/*
 		 * Only add will be displayed
 		 */
-		if ($item->getDataValue('network') === NETWORK_MAIL && local_user() != $item->getDataValue('uid')) {
+		if ($item->getDataValue('network') === Protocol::MAIL && local_user() != $item->getDataValue('uid')) {
 			logger('[WARN] Conversation::addThread : Thread is a mail ('. $item->getId() .').', LOGGER_DEBUG);
 			return false;
 		}
@@ -176,7 +177,7 @@ class Thread extends BaseObject
 		$i = 0;
 
 		foreach ($this->parents as $item) {
-			if ($item->getDataValue('network') === NETWORK_MAIL && local_user() != $item->getDataValue('uid')) {
+			if ($item->getDataValue('network') === Protocol::MAIL && local_user() != $item->getDataValue('uid')) {
 				continue;
 			}
 
diff --git a/src/Protocol/DFRN.php b/src/Protocol/DFRN.php
index 296949ddc..55d635d2e 100644
--- a/src/Protocol/DFRN.php
+++ b/src/Protocol/DFRN.php
@@ -17,6 +17,7 @@ use Friendica\Content\Text\HTML;
 use Friendica\Core\Addon;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -272,7 +273,7 @@ class DFRN
 
 		foreach ($items as $item) {
 			// prevent private email from leaking.
-			if ($item['network'] == NETWORK_MAIL) {
+			if ($item['network'] == Protocol::MAIL) {
 				continue;
 			}
 
@@ -1533,7 +1534,7 @@ class DFRN
 		$fields = ['id', 'uid', 'url', 'network', 'avatar-date', 'avatar', 'name-date', 'uri-date', 'addr',
 			'name', 'nick', 'about', 'location', 'keywords', 'xmpp', 'bdyear', 'bd', 'hidden', 'contact-type'];
 		$condition = ["`uid` = ? AND `nurl` = ? AND `network` != ?",
-			$importer["importer_uid"], normalise_link($author["link"]), NETWORK_STATUSNET];
+			$importer["importer_uid"], normalise_link($author["link"]), Protocol::STATUSNET];
 		$contact_old = DBA::selectFirst('contact', $fields, $condition);
 
 		if (DBA::isResult($contact_old)) {
@@ -2822,7 +2823,7 @@ class DFRN
 
 		$header = [];
 		$header["uid"] = $importer["importer_uid"];
-		$header["network"] = NETWORK_DFRN;
+		$header["network"] = Protocol::DFRN;
 		$header["wall"] = 0;
 		$header["origin"] = 0;
 		$header["contact-id"] = $importer["id"];
@@ -2956,7 +2957,7 @@ class DFRN
 			$r = q("SELECT * FROM contact WHERE nick = '%s'
 					AND network = '%s' AND uid = %d  AND url LIKE '%%%s%%' LIMIT 1",
 				DBA::escape($contact_nick),
-				DBA::escape(NETWORK_DFRN),
+				DBA::escape(Protocol::DFRN),
 				intval(local_user()),
 				DBA::escape($baseurl)
 			);
diff --git a/src/Protocol/Diaspora.php b/src/Protocol/Diaspora.php
index 5036aa357..40e2780f8 100644
--- a/src/Protocol/Diaspora.php
+++ b/src/Protocol/Diaspora.php
@@ -16,6 +16,7 @@ use Friendica\Core\Cache;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
@@ -176,7 +177,7 @@ class Diaspora
 	{
 		$fields = ['created' => DateTimeFormat::utcNow(),
 			'name' => 'relay', 'nick' => 'relay',
-			'url' => $server_url, 'network' => NETWORK_DIASPORA,
+			'url' => $server_url, 'network' => Protocol::DIASPORA,
 			'batch' => $server_url . '/receive/public',
 			'rel' => Contact::FOLLOWER, 'blocked' => false,
 			'pending' => false, 'writable' => true];
@@ -899,7 +900,7 @@ class Diaspora
 	{
 		$update = false;
 
-		$person = DBA::selectFirst('fcontact', [], ['network' => NETWORK_DIASPORA, 'addr' => $handle]);
+		$person = DBA::selectFirst('fcontact', [], ['network' => Protocol::DIASPORA, 'addr' => $handle]);
 		if (DBA::isResult($person)) {
 			logger("In cache " . print_r($person, true), LOGGER_DEBUG);
 
@@ -916,15 +917,15 @@ class Diaspora
 
 		if (!DBA::isResult($person) || $update) {
 			logger("create or refresh", LOGGER_DEBUG);
-			$r = Probe::uri($handle, NETWORK_DIASPORA);
+			$r = Probe::uri($handle, Protocol::DIASPORA);
 
 			// Note that Friendica contacts will return a "Diaspora person"
 			// if Diaspora connectivity is enabled on their server
-			if ($r && ($r["network"] === NETWORK_DIASPORA)) {
+			if ($r && ($r["network"] === Protocol::DIASPORA)) {
 				self::updateFContact($r);
 
 				// Fetch the updated or added contact
-				$person = DBA::selectFirst('fcontact', [], ['network' => NETWORK_DIASPORA, 'addr' => $handle]);
+				$person = DBA::selectFirst('fcontact', [], ['network' => Protocol::DIASPORA, 'addr' => $handle]);
 				if (!DBA::isResult($person)) {
 					$person = $r;
 				}
@@ -1017,7 +1018,7 @@ class Diaspora
 
 		$r = q(
 			"SELECT `url` FROM `fcontact` WHERE `url` != '' AND `network` = '%s' AND `guid` = '%s'",
-			DBA::escape(NETWORK_DIASPORA),
+			DBA::escape(Protocol::DIASPORA),
 			DBA::escape($fcontact_guid)
 		);
 
@@ -1419,7 +1420,7 @@ class Diaspora
 			$network = $contact["network"];
 		} else {
 			$cid = $def_contact["id"];
-			$network = NETWORK_DIASPORA;
+			$network = Protocol::DIASPORA;
 		}
 
 		return ["cid" => $cid, "network" => $network];
@@ -1459,7 +1460,7 @@ class Diaspora
 			}
 		}
 
-		if ($contact["network"] == NETWORK_DFRN) {
+		if ($contact["network"] == Protocol::DFRN) {
 			return str_replace("/profile/" . $contact["nick"] . "/", "/display/" . $guid, $contact["url"] . "/");
 		}
 
@@ -1509,7 +1510,7 @@ class Diaspora
 
 		// change the technical stuff in contact and gcontact
 		$data = Probe::uri($new_handle);
-		if ($data['network'] == NETWORK_PHANTOM) {
+		if ($data['network'] == Protocol::PHANTOM) {
 			logger('Account for '.$new_handle." couldn't be probed.");
 			return false;
 		}
@@ -2281,7 +2282,7 @@ class Diaspora
 
 		DBA::update('contact', $fields, ['id' => $contact['id']]);
 
-		$gcontact = ["url" => $contact["url"], "network" => NETWORK_DIASPORA, "generation" => 2,
+		$gcontact = ["url" => $contact["url"], "network" => Protocol::DIASPORA, "generation" => 2,
 					"photo" => $image_url, "name" => $name, "location" => $location,
 					"about" => $about, "birthday" => $birthday, "gender" => $gender,
 					"addr" => $author, "nick" => $nick, "keywords" => $keywords,
@@ -2392,7 +2393,7 @@ class Diaspora
 
 		$ret = self::personByHandle($author);
 
-		if (!$ret || ($ret["network"] != NETWORK_DIASPORA)) {
+		if (!$ret || ($ret["network"] != Protocol::DIASPORA)) {
 			logger("Cannot resolve diaspora handle ".$author." for ".$recipient);
 			return false;
 		}
@@ -2617,7 +2618,7 @@ class Diaspora
 
 		$datarray["uid"] = $importer["uid"];
 		$datarray["contact-id"] = $contact["id"];
-		$datarray["network"]  = NETWORK_DIASPORA;
+		$datarray["network"]  = Protocol::DIASPORA;
 
 		$datarray["author-link"] = $contact["url"];
 		$datarray["author-id"] = Contact::getIdForURL($contact["url"], 0);
@@ -2845,7 +2846,7 @@ class Diaspora
 
 		$datarray["uid"] = $importer["uid"];
 		$datarray["contact-id"] = $contact["id"];
-		$datarray["network"] = NETWORK_DIASPORA;
+		$datarray["network"] = Protocol::DIASPORA;
 
 		$datarray["author-link"] = $contact["url"];
 		$datarray["author-id"] = Contact::getIdForURL($contact["url"], 0);
@@ -3110,7 +3111,7 @@ class Diaspora
 			if (!$no_queue && ($contact['contact-type'] != Contact::ACCOUNT_TYPE_RELAY)) {
 				logger("queue message");
 				// queue message for redelivery
-				Queue::add($contact["id"], NETWORK_DIASPORA, $envelope, $public_batch, $guid);
+				Queue::add($contact["id"], Protocol::DIASPORA, $envelope, $public_batch, $guid);
 			}
 
 			// The message could not be delivered. We mark the contact as "dead"
@@ -3167,7 +3168,7 @@ class Diaspora
 		$envelope = self::buildMessage($msg, $owner, $contact, $owner['uprvkey'], $contact['pubkey'], $public_batch);
 
 		if ($spool) {
-			Queue::add($contact['id'], NETWORK_DIASPORA, $envelope, $public_batch, $guid);
+			Queue::add($contact['id'], Protocol::DIASPORA, $envelope, $public_batch, $guid);
 			return true;
 		} else {
 			$return_code = self::transmit($owner, $contact, $envelope, $public_batch, false, $guid);
@@ -3358,7 +3359,7 @@ class Diaspora
 		}
 
 		if (($guid != "") && $complete) {
-			$condition = ['guid' => $guid, 'network' => [NETWORK_DFRN, NETWORK_DIASPORA]];
+			$condition = ['guid' => $guid, 'network' => [Protocol::DFRN, Protocol::DIASPORA]];
 			$item = Item::selectFirst(['contact-id'], $condition);
 			if (DBA::isResult($item)) {
 				$ret= [];
@@ -4133,7 +4134,7 @@ class Diaspora
 			$recips = q(
 				"SELECT `id`,`name`,`network`,`pubkey`,`notify` FROM `contact` WHERE `network` = '%s'
 				AND `uid` = %d AND `rel` != %d",
-				DBA::escape(NETWORK_DIASPORA),
+				DBA::escape(Protocol::DIASPORA),
 				intval($uid),
 				intval(Contact::SHARING)
 			);
diff --git a/src/Protocol/Email.php b/src/Protocol/Email.php
index 0963feb0d..00122e2ea 100644
--- a/src/Protocol/Email.php
+++ b/src/Protocol/Email.php
@@ -5,6 +5,7 @@
 namespace Friendica\Protocol;
 
 use Friendica\Content\Text\HTML;
+use Friendica\Core\Protocol;
 
 /**
  * @brief Email class
@@ -308,7 +309,7 @@ class Email
 	}
 
 	/**
-	 * Function send is used by NETWORK_EMAIL and NETWORK_EMAIL2 code
+	 * Function send is used by Protocol::EMAIL and Protocol::EMAIL2 code
 	 * (not to notify the user, but to send items to email contacts)
 	 *
 	 * @param string $addr    address
diff --git a/src/Protocol/Feed.php b/src/Protocol/Feed.php
index 7bae9ef58..c9c750a83 100644
--- a/src/Protocol/Feed.php
+++ b/src/Protocol/Feed.php
@@ -9,6 +9,7 @@ namespace Friendica\Protocol;
 use DOMDocument;
 use DOMXPath;
 use Friendica\Content\Text\HTML;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Item;
@@ -187,7 +188,7 @@ class Feed {
 
 		$header = [];
 		$header["uid"] = $importer["uid"];
-		$header["network"] = NETWORK_FEED;
+		$header["network"] = Protocol::FEED;
 		$header["wall"] = 0;
 		$header["origin"] = 0;
 		$header["gravity"] = GRAVITY_PARENT;
@@ -244,7 +245,7 @@ class Feed {
 
 			if (!$simulate) {
 				$condition = ["`uid` = ? AND `uri` = ? AND `network` IN (?, ?)",
-					$importer["uid"], $item["uri"], NETWORK_FEED, NETWORK_DFRN];
+					$importer["uid"], $item["uri"], Protocol::FEED, Protocol::DFRN];
 				$previous = Item::selectFirst(['id'], $condition);
 				if (DBA::isResult($previous)) {
 					logger("Item with uri ".$item["uri"]." for user ".$importer["uid"]." already existed under id ".$previous["id"], LOGGER_DEBUG);
diff --git a/src/Protocol/OStatus.php b/src/Protocol/OStatus.php
index bab85515b..80c6edbe9 100644
--- a/src/Protocol/OStatus.php
+++ b/src/Protocol/OStatus.php
@@ -12,6 +12,7 @@ use Friendica\Core\Cache;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
 use Friendica\Core\Lock;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -75,7 +76,7 @@ class OStatus
 		$contact = null;
 		if ($aliaslink != '') {
 			$condition = ["`uid` = ? AND `alias` = ? AND `network` != ? AND `rel` IN (?, ?)",
-					$importer["uid"], $aliaslink, NETWORK_STATUSNET,
+					$importer["uid"], $aliaslink, Protocol::STATUSNET,
 					Contact::SHARING, Contact::FRIEND];
 			$contact = DBA::selectFirst('contact', [], $condition);
 		}
@@ -87,13 +88,13 @@ class OStatus
 
 			$condition = ["`uid` = ? AND `nurl` IN (?, ?) AND `network` != ? AND `rel` IN (?, ?)",
 					$importer["uid"], normalise_link($author["author-link"]), normalise_link($aliaslink),
-					NETWORK_STATUSNET, Contact::SHARING, Contact::FRIEND];
+					Protocol::STATUSNET, Contact::SHARING, Contact::FRIEND];
 			$contact = DBA::selectFirst('contact', [], $condition);
 		}
 
 		if (!DBA::isResult($contact) && ($addr != '')) {
 			$condition = ["`uid` = ? AND `addr` = ? AND `network` != ? AND `rel` IN (?, ?)",
-					$importer["uid"], $addr, NETWORK_STATUSNET,
+					$importer["uid"], $addr, Protocol::STATUSNET,
 					Contact::SHARING, Contact::FRIEND];
 			$contact = DBA::selectFirst('contact', [], $condition);
 		}
@@ -135,7 +136,7 @@ class OStatus
 		$author["owner-id"] = $author["author-id"];
 
 		// Only update the contacts if it is an OStatus contact
-		if (DBA::isResult($contact) && ($contact['id'] > 0) && !$onlyfetch && ($contact["network"] == NETWORK_OSTATUS)) {
+		if (DBA::isResult($contact) && ($contact['id'] > 0) && !$onlyfetch && ($contact["network"] == Protocol::OSTATUS)) {
 
 			// Update contact data
 			$current = $contact;
@@ -345,7 +346,7 @@ class OStatus
 
 		$header = [];
 		$header["uid"] = $importer["uid"];
-		$header["network"] = NETWORK_OSTATUS;
+		$header["network"] = Protocol::OSTATUS;
 		$header["wall"] = 0;
 		$header["origin"] = 0;
 		$header["gravity"] = GRAVITY_COMMENT;
@@ -799,7 +800,7 @@ class OStatus
 			$conv_data = [];
 
 			$conv_data['protocol'] = Conversation::PARCEL_SPLIT_CONVERSATION;
-			$conv_data['network'] = NETWORK_OSTATUS;
+			$conv_data['network'] = Protocol::OSTATUS;
 			$conv_data['uri'] = XML::getFirstNodeValue($xpath, 'atom:id/text()', $entry);
 
 			$inreplyto = $xpath->query('thr:in-reply-to', $entry);
@@ -1647,7 +1648,7 @@ class OStatus
 		$title = self::entryHeader($doc, $entry, $owner, $item, $toplevel);
 
 		$condition = ['uid' => $owner["uid"], 'guid' => $repeated_guid, 'private' => false,
-			'network' => [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS]];
+			'network' => [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS]];
 		$repeated_item = Item::selectFirst([], $condition);
 		if (!DBA::isResult($repeated_item)) {
 			return false;
@@ -1745,7 +1746,7 @@ class OStatus
 		$object = $doc->createElement("activity:object");
 		XML::addElement($doc, $object, "activity:object-type", ACTIVITY_OBJ_PERSON);
 
-		if ($contact['network'] == NETWORK_PHANTOM) {
+		if ($contact['network'] == Protocol::PHANTOM) {
 			XML::addElement($doc, $object, "id", $contact['url']);
 			return $object;
 		}
@@ -2161,7 +2162,7 @@ class OStatus
 
 		$condition = ["`uid` = ? AND `created` > ? AND NOT `deleted`
 			AND NOT `private` AND `visible` AND `wall` AND `parent-network` IN (?, ?)",
-			$owner["uid"], $check_date, NETWORK_OSTATUS, NETWORK_DFRN];
+			$owner["uid"], $check_date, Protocol::OSTATUS, Protocol::DFRN];
 
 		if ($filter === 'comments') {
 			$condition[0] .= " AND `object-type` = ? ";
diff --git a/src/Protocol/PortableContact.php b/src/Protocol/PortableContact.php
index a94affd04..1c44947f5 100644
--- a/src/Protocol/PortableContact.php
+++ b/src/Protocol/PortableContact.php
@@ -14,6 +14,7 @@ use DOMXPath;
 use Exception;
 use Friendica\Content\Text\HTML;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
 use Friendica\Model\GContact;
@@ -228,7 +229,7 @@ class PortableContact
 			$friendica = preg_replace("=(https?://)(.*)/profile/(.*)=ism", "$1$2", $profile);
 			if ($friendica != $profile) {
 				$server_url = $friendica;
-				$network = NETWORK_DFRN;
+				$network = Protocol::DFRN;
 			}
 		}
 
@@ -236,7 +237,7 @@ class PortableContact
 			$diaspora = preg_replace("=(https?://)(.*)/u/(.*)=ism", "$1$2", $profile);
 			if ($diaspora != $profile) {
 				$server_url = $diaspora;
-				$network = NETWORK_DIASPORA;
+				$network = Protocol::DIASPORA;
 			}
 		}
 
@@ -244,7 +245,7 @@ class PortableContact
 			$red = preg_replace("=(https?://)(.*)/channel/(.*)=ism", "$1$2", $profile);
 			if ($red != $profile) {
 				$server_url = $red;
-				$network = NETWORK_DIASPORA;
+				$network = Protocol::DIASPORA;
 			}
 		}
 
@@ -253,7 +254,7 @@ class PortableContact
 			$mastodon = preg_replace("=(https?://)(.*)/users/(.*)=ism", "$1$2", $profile);
 			if ($mastodon != $profile) {
 				$server_url = $mastodon;
-				$network = NETWORK_OSTATUS;
+				$network = Protocol::OSTATUS;
 			}
 		}
 
@@ -262,7 +263,7 @@ class PortableContact
 			$ostatus = preg_replace("=(https?://)(.*)/user/(.*)=ism", "$1$2", $profile);
 			if ($ostatus != $profile) {
 				$server_url = $ostatus;
-				$network = NETWORK_OSTATUS;
+				$network = Protocol::OSTATUS;
 			}
 		}
 
@@ -271,7 +272,7 @@ class PortableContact
 			$base = preg_replace("=(https?://)(.*?)/(.*)=ism", "$1$2", $profile);
 			if ($base != $profile) {
 				$server_url = $base;
-				$network = NETWORK_PHANTOM;
+				$network = Protocol::PHANTOM;
 			}
 		}
 
@@ -332,7 +333,7 @@ class PortableContact
 			$server_url = normalise_link(self::detectServer($profile));
 		}
 
-		if (!in_array($gcontacts[0]["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_FEED, NETWORK_OSTATUS, ""])) {
+		if (!in_array($gcontacts[0]["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::FEED, Protocol::OSTATUS, ""])) {
 			logger("Profile ".$profile.": Network type ".$gcontacts[0]["network"]." can't be checked", LOGGER_DEBUG);
 			return false;
 		}
@@ -350,7 +351,7 @@ class PortableContact
 			$contact['server_url'] = $server_url;
 		}
 
-		if (in_array($gcontacts[0]["network"], ["", NETWORK_FEED])) {
+		if (in_array($gcontacts[0]["network"], ["", Protocol::FEED])) {
 			$server = q(
 				"SELECT `network` FROM `gserver` WHERE `nurl` = '%s' AND `network` != ''",
 				DBA::escape(normalise_link($server_url))
@@ -445,7 +446,7 @@ class PortableContact
 
 		// Is the profile link the alternate OStatus link notation? (http://domain.tld/user/4711)
 		// Then check the other link and delete this one
-		if (($data["network"] == NETWORK_OSTATUS) && self::alternateOStatusUrl($profile)
+		if (($data["network"] == Protocol::OSTATUS) && self::alternateOStatusUrl($profile)
 			&& (normalise_link($profile) == normalise_link($data["alias"]))
 			&& (normalise_link($profile) != normalise_link($data["url"]))
 		) {
@@ -469,7 +470,7 @@ class PortableContact
 			return false;
 		}
 
-		if (($data["poll"] == "") || (in_array($data["network"], [NETWORK_FEED, NETWORK_PHANTOM]))) {
+		if (($data["poll"] == "") || (in_array($data["network"], [Protocol::FEED, Protocol::PHANTOM]))) {
 			$fields = ['last_failure' => DateTimeFormat::utcNow()];
 			DBA::update('gcontact', $fields, ['nurl' => normalise_link($profile)]);
 
@@ -629,7 +630,7 @@ class PortableContact
 			if ($url['type'] == 'zot') {
 				$server = [];
 				$server["platform"] = 'Hubzilla';
-				$server["network"] = NETWORK_DIASPORA;
+				$server["network"] = Protocol::DIASPORA;
 				return $server;
 			}
 		}
@@ -757,13 +758,13 @@ class PortableContact
 		}
 
 		if ($gnusocial) {
-			$server['network'] = NETWORK_OSTATUS;
+			$server['network'] = Protocol::OSTATUS;
 		}
 		if ($diaspora) {
-			$server['network'] = NETWORK_DIASPORA;
+			$server['network'] = Protocol::DIASPORA;
 		}
 		if ($friendica) {
-			$server['network'] = NETWORK_DFRN;
+			$server['network'] = Protocol::DFRN;
 		}
 
 		if (!$server) {
@@ -838,11 +839,11 @@ class PortableContact
 		}
 
 		if ($gnusocial) {
-			$server['network'] = NETWORK_OSTATUS;
+			$server['network'] = Protocol::OSTATUS;
 		} elseif ($diaspora) {
-			$server['network'] = NETWORK_DIASPORA;
+			$server['network'] = Protocol::DIASPORA;
 		} elseif ($friendica) {
-			$server['network'] = NETWORK_DFRN;
+			$server['network'] = Protocol::DFRN;
 		}
 
 		if (empty($server)) {
@@ -883,7 +884,7 @@ class PortableContact
 						$server = [];
 						$server["platform"] = $version_part[0];
 						$server["version"] = $version_part[1];
-						$server["network"] = NETWORK_DFRN;
+						$server["network"] = Protocol::DFRN;
 					}
 				}
 			}
@@ -903,7 +904,7 @@ class PortableContact
 					$server = [];
 					$server["platform"] = $attr['content'];
 					$server["version"] = "";
-					$server["network"] = NETWORK_DIASPORA;
+					$server["network"] = Protocol::DIASPORA;
 				}
 			}
 		}
@@ -1106,14 +1107,14 @@ class PortableContact
 							$platform = "Diaspora";
 							$version = trim(str_replace("X-Diaspora-Version:", "", $line));
 							$version = trim(str_replace("x-diaspora-version:", "", $version));
-							$network = NETWORK_DIASPORA;
+							$network = Protocol::DIASPORA;
 							$versionparts = explode("-", $version);
 							$version = $versionparts[0];
 						}
 
 						if (stristr($line, 'Server: Mastodon')) {
 							$platform = "Mastodon";
-							$network = NETWORK_OSTATUS;
+							$network = Protocol::OSTATUS;
 						}
 					}
 				}
@@ -1132,7 +1133,7 @@ class PortableContact
 				// Remove junk that some GNU Social servers return
 				$version = str_replace(chr(239).chr(187).chr(191), "", $serverret["body"]);
 				$version = trim($version, '"');
-				$network = NETWORK_OSTATUS;
+				$network = Protocol::OSTATUS;
 			}
 
 			// Test for GNU Social
@@ -1144,7 +1145,7 @@ class PortableContact
 				// Remove junk that some GNU Social servers return
 				$version = str_replace(chr(239) . chr(187) . chr(191), "", $serverret["body"]);
 				$version = trim($version, '"');
-				$network = NETWORK_OSTATUS;
+				$network = Protocol::OSTATUS;
 			}
 
 			// Test for Mastodon
@@ -1159,7 +1160,7 @@ class PortableContact
 					$version = $data['version'];
 					$site_name = $data['title'];
 					$info = $data['description'];
-					$network = NETWORK_OSTATUS;
+					$network = Protocol::OSTATUS;
 				}
 
 				if (!empty($data['stats']['user_count'])) {
@@ -1183,7 +1184,7 @@ class PortableContact
 				if (isset($data['url'])) {
 					$platform = $data['platform'];
 					$version = $data['version'];
-					$network = NETWORK_DIASPORA;
+					$network = Protocol::DIASPORA;
 				}
 
 				if (!empty($data['site_name'])) {
@@ -1221,19 +1222,19 @@ class PortableContact
 						if (isset($data['site']['platform'])) {
 							$platform = $data['site']['platform']['PLATFORM_NAME'];
 							$version = $data['site']['platform']['STD_VERSION'];
-							$network = NETWORK_DIASPORA;
+							$network = Protocol::DIASPORA;
 						}
 
 						if (isset($data['site']['BlaBlaNet'])) {
 							$platform = $data['site']['BlaBlaNet']['PLATFORM_NAME'];
 							$version = $data['site']['BlaBlaNet']['STD_VERSION'];
-							$network = NETWORK_DIASPORA;
+							$network = Protocol::DIASPORA;
 						}
 
 						if (isset($data['site']['hubzilla'])) {
 							$platform = $data['site']['hubzilla']['PLATFORM_NAME'];
 							$version = $data['site']['hubzilla']['RED_VERSION'];
-							$network = NETWORK_DIASPORA;
+							$network = Protocol::DIASPORA;
 						}
 
 						if (isset($data['site']['redmatrix'])) {
@@ -1244,13 +1245,13 @@ class PortableContact
 							}
 
 							$version = $data['site']['redmatrix']['RED_VERSION'];
-							$network = NETWORK_DIASPORA;
+							$network = Protocol::DIASPORA;
 						}
 
 						if (isset($data['site']['friendica'])) {
 							$platform = $data['site']['friendica']['FRIENDICA_PLATFORM'];
 							$version = $data['site']['friendica']['FRIENDICA_VERSION'];
-							$network = NETWORK_DFRN;
+							$network = Protocol::DFRN;
 						}
 
 						$site_name = $data['site']['name'];
@@ -1306,7 +1307,7 @@ class PortableContact
 				}
 
 				if ($platform == "Diaspora") {
-					$network = NETWORK_DIASPORA;
+					$network = Protocol::DIASPORA;
 				}
 
 				if (!empty($data['registrations_open']) && $data['registrations_open']) {
@@ -1348,7 +1349,7 @@ class PortableContact
 
 		// Check for noscrape
 		// Friendica servers could be detected as OStatus servers
-		if (!$failure && in_array($network, [NETWORK_DFRN, NETWORK_OSTATUS])) {
+		if (!$failure && in_array($network, [Protocol::DFRN, Protocol::OSTATUS])) {
 			$serverret = Network::curl($server_url . "/friendica/json");
 
 			if (!$serverret["success"]) {
@@ -1359,7 +1360,7 @@ class PortableContact
 				$data = json_decode($serverret["body"], true);
 
 				if (isset($data['version'])) {
-					$network = NETWORK_DFRN;
+					$network = Protocol::DFRN;
 
 					if (!empty($data['no_scrape_url'])) {
 						$noscrape = $data['no_scrape_url'];
@@ -1423,7 +1424,7 @@ class PortableContact
 			DBA::insert('gserver', $fields);
 		}
 
-		if (!$failure && in_array($fields['network'], [NETWORK_DFRN, NETWORK_DIASPORA])) {
+		if (!$failure && in_array($fields['network'], [Protocol::DFRN, Protocol::DIASPORA])) {
 			self::discoverRelay($server_url);
 		}
 
@@ -1485,7 +1486,7 @@ class PortableContact
 		$fields = [];
 		if (isset($data['protocols'])) {
 			if (isset($data['protocols']['diaspora'])) {
-				$fields['network'] = NETWORK_DIASPORA;
+				$fields['network'] = Protocol::DIASPORA;
 
 				if (isset($data['protocols']['diaspora']['receive'])) {
 					$fields['batch'] = $data['protocols']['diaspora']['receive'];
@@ -1495,7 +1496,7 @@ class PortableContact
 			}
 
 			if (isset($data['protocols']['dfrn'])) {
-				$fields['network'] = NETWORK_DFRN;
+				$fields['network'] = Protocol::DFRN;
 
 				if (isset($data['protocols']['dfrn']['receive'])) {
 					$fields['batch'] = $data['protocols']['dfrn']['receive'];
@@ -1518,9 +1519,9 @@ class PortableContact
 			WHERE `network` IN ('%s', '%s', '%s') AND `last_contact` > `last_failure`
 			ORDER BY `last_contact`
 			LIMIT 1000",
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_OSTATUS)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::OSTATUS)
 		);
 
 		if (!DBA::isResult($r)) {
diff --git a/src/Worker/Cron.php b/src/Worker/Cron.php
index edd3e22ef..61077ae73 100644
--- a/src/Worker/Cron.php
+++ b/src/Worker/Cron.php
@@ -7,6 +7,7 @@ namespace Friendica\Worker;
 use Friendica\BaseObject;
 use Friendica\Core\Addon;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -188,11 +189,11 @@ class Cron
 					AND `contact`.`network` IN ('%s', '%s', '%s', '%s', '%s') $sql_extra
 					AND NOT `contact`.`self` AND NOT `contact`.`blocked`
 				WHERE NOT `user`.`account_expired` AND NOT `user`.`account_removed` $abandon_sql",
-			DBA::escape(NETWORK_DFRN),
-			DBA::escape(NETWORK_OSTATUS),
-			DBA::escape(NETWORK_DIASPORA),
-			DBA::escape(NETWORK_FEED),
-			DBA::escape(NETWORK_MAIL)
+			DBA::escape(Protocol::DFRN),
+			DBA::escape(Protocol::OSTATUS),
+			DBA::escape(Protocol::DIASPORA),
+			DBA::escape(Protocol::FEED),
+			DBA::escape(Protocol::MAIL)
 		);
 
 		if (!DBA::isResult($contacts)) {
@@ -206,11 +207,11 @@ class Cron
 			}
 
 			// Friendica and OStatus are checked once a day
-			if (in_array($contact['network'], [NETWORK_DFRN, NETWORK_OSTATUS])) {
+			if (in_array($contact['network'], [Protocol::DFRN, Protocol::OSTATUS])) {
 				$contact['priority'] = 2;
 			}
 
-			if ($contact['subhub'] && in_array($contact['network'], [NETWORK_DFRN, NETWORK_OSTATUS])) {
+			if ($contact['subhub'] && in_array($contact['network'], [Protocol::DFRN, Protocol::OSTATUS])) {
 				/*
 				 * We should be getting everything via a hub. But just to be sure, let's check once a day.
 				 * (You can make this more or less frequent if desired by setting 'pushpoll_frequency' appropriately)
@@ -222,7 +223,7 @@ class Cron
 			}
 
 			// Check Diaspora contacts or followers once a week
-			if (($contact["network"] == NETWORK_DIASPORA) || ($contact["rel"] == Contact::FOLLOWER)) {
+			if (($contact["network"] == Protocol::DIASPORA) || ($contact["rel"] == Contact::FOLLOWER)) {
 				$contact['priority'] = 4;
 			}
 
@@ -277,7 +278,7 @@ class Cron
 				}
 			}
 
-			if (($contact['network'] == NETWORK_FEED) && ($contact['priority'] <= 3)) {
+			if (($contact['network'] == Protocol::FEED) && ($contact['priority'] <= 3)) {
 				$priority = PRIORITY_MEDIUM;
 			} elseif ($contact['archive']) {
 				$priority = PRIORITY_NEGLIGIBLE;
diff --git a/src/Worker/CronJobs.php b/src/Worker/CronJobs.php
index 19e6fbaf7..a3916ad97 100644
--- a/src/Worker/CronJobs.php
+++ b/src/Worker/CronJobs.php
@@ -8,6 +8,7 @@ use Friendica\App;
 use Friendica\BaseObject;
 use Friendica\Core\Cache;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Database\PostUpdate;
 use Friendica\Model\Contact;
@@ -231,12 +232,12 @@ class CronJobs
 
 		$r = q("SELECT `id`, `url` FROM `contact`
 			WHERE `network` = '%s' AND (`batch` = '' OR `notify` = '' OR `poll` = '' OR pubkey = '')
-				ORDER BY RAND() LIMIT 50", DBA::escape(NETWORK_DIASPORA));
+				ORDER BY RAND() LIMIT 50", DBA::escape(Protocol::DIASPORA));
 		if (!DBA::isResult($r)) {
 			return;
 		}
 
-		foreach ($r AS $contact) {
+		foreach ($r as $contact) {
 			// Quit the loop after 3 minutes
 			if (time() > ($starttime + 180)) {
 				return;
@@ -247,7 +248,7 @@ class CronJobs
 			}
 
 			$data = Probe::uri($contact["url"]);
-			if ($data["network"] != NETWORK_DIASPORA) {
+			if ($data["network"] != Protocol::DIASPORA) {
 				continue;
 			}
 
diff --git a/src/Worker/Delivery.php b/src/Worker/Delivery.php
index 32bcdfcc4..f47487015 100644
--- a/src/Worker/Delivery.php
+++ b/src/Worker/Delivery.php
@@ -7,6 +7,7 @@ namespace Friendica\Worker;
 use Friendica\BaseObject;
 use Friendica\Core\Config;
 use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
 use Friendica\Core\System;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -156,23 +157,23 @@ class Delivery extends BaseObject
 
 		// Transmit via Diaspora if the thread had started as Diaspora post
 		// This is done since the uri wouldn't match (Diaspora doesn't transmit it)
-		if (isset($parent) && ($parent['network'] == NETWORK_DIASPORA) && ($contact['network'] == NETWORK_DFRN)) {
-			$contact['network'] = NETWORK_DIASPORA;
+		if (isset($parent) && ($parent['network'] == Protocol::DIASPORA) && ($contact['network'] == Protocol::DFRN)) {
+			$contact['network'] = Protocol::DIASPORA;
 		}
 
 		logger("Delivering " . $cmd . " followup=$followup - via network " . $contact['network']);
 
 		switch ($contact['network']) {
 
-			case NETWORK_DFRN:
+			case Protocol::DFRN:
 				self::deliverDFRN($cmd, $contact, $owner, $items, $target_item, $public_message, $top_level, $followup);
 				break;
 
-			case NETWORK_DIASPORA:
+			case Protocol::DIASPORA:
 				self::deliverDiaspora($cmd, $contact, $owner, $items, $target_item, $public_message, $top_level, $followup);
 				break;
 
-			case NETWORK_OSTATUS:
+			case Protocol::OSTATUS:
 				// Do not send to otatus if we are not configured to send to public networks
 				if ($owner['prvnets']) {
 					break;
@@ -185,7 +186,7 @@ class Delivery extends BaseObject
 				// This is done in "notifier.php" (See "url_recipients" and "push_notify")
 				break;
 
-			case NETWORK_MAIL:
+			case Protocol::MAIL:
 				self::deliverMail($cmd, $contact, $owner, $target_item);
 				break;
 
@@ -316,7 +317,7 @@ class Delivery extends BaseObject
 
 		if ($deliver_status < 0) {
 			logger('Delivery failed: queuing message ' . $target_item["guid"] );
-			Queue::add($contact['id'], NETWORK_DFRN, $atom, false, $target_item['guid']);
+			Queue::add($contact['id'], Protocol::DFRN, $atom, false, $target_item['guid']);
 		}
 
 		if (($deliver_status >= 200) && ($deliver_status <= 299)) {
diff --git a/src/Worker/DiscoverPoCo.php b/src/Worker/DiscoverPoCo.php
index 89b3a0a11..bf1c2a64a 100644
--- a/src/Worker/DiscoverPoCo.php
+++ b/src/Worker/DiscoverPoCo.php
@@ -6,6 +6,7 @@ namespace Friendica\Worker;
 
 use Friendica\Core\Cache;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
 use Friendica\Model\GContact;
@@ -147,8 +148,8 @@ class DiscoverPoCo
 				WHERE `last_contact` < UTC_TIMESTAMP - INTERVAL 1 MONTH AND
 					`last_failure` < UTC_TIMESTAMP - INTERVAL 1 MONTH AND
 					`network` IN ('%s', '%s', '%s', '%s', '') ORDER BY rand()",
-				DBA::escape(NETWORK_DFRN), DBA::escape(NETWORK_DIASPORA),
-				DBA::escape(NETWORK_OSTATUS), DBA::escape(NETWORK_FEED));
+				DBA::escape(Protocol::DFRN), DBA::escape(Protocol::DIASPORA),
+				DBA::escape(Protocol::OSTATUS), DBA::escape(Protocol::FEED));
 
 		if (!$users) {
 			return;
@@ -159,13 +160,13 @@ class DiscoverPoCo
 
 			$urlparts = parse_url($user["url"]);
 			if (!isset($urlparts["scheme"])) {
-				DBA::update('gcontact', ['network' => NETWORK_PHANTOM],
+				DBA::update('gcontact', ['network' => Protocol::PHANTOM],
 					['nurl' => normalise_link($user["url"])]);
 				continue;
 			 }
 
 			if (in_array($urlparts["host"], ["twitter.com", "identi.ca"])) {
-				$networks = ["twitter.com" => NETWORK_TWITTER, "identi.ca" => NETWORK_PUMPIO];
+				$networks = ["twitter.com" => Protocol::TWITTER, "identi.ca" => Protocol::PUMPIO];
 
 				DBA::update('gcontact', ['network' => $networks[$urlparts["host"]]],
 					['nurl' => normalise_link($user["url"])]);
@@ -182,7 +183,7 @@ class DiscoverPoCo
 				$server_url = $user["server_url"];
 			}
 
-			if ((($server_url == "") && ($user["network"] == NETWORK_FEED)) || $force_update || PortableContact::checkServer($server_url, $user["network"])) {
+			if ((($server_url == "") && ($user["network"] == Protocol::FEED)) || $force_update || PortableContact::checkServer($server_url, $user["network"])) {
 				logger('Check profile '.$user["url"]);
 				Worker::add(PRIORITY_LOW, "DiscoverPoCo", "check_profile", $user["url"]);
 
@@ -241,7 +242,7 @@ class DiscoverPoCo
 				}
 
 				$data = Probe::uri($jj->url);
-				if ($data["network"] == NETWORK_DFRN) {
+				if ($data["network"] == Protocol::DFRN) {
 					logger("Profile ".$jj->url." is reachable (".$search.")", LOGGER_DEBUG);
 					logger("Add profile ".$jj->url." to local directory (".$search.")", LOGGER_DEBUG);
 
@@ -288,7 +289,7 @@ class DiscoverPoCo
 		/// @TODO find all those and convert to all lower-case which is a keyword then
 		foreach ($contacts->data AS $user) {
 			$contact = Probe::uri($user->site_address."/".$user->name);
-			if ($contact["network"] != NETWORK_PHANTOM) {
+			if ($contact["network"] != Protocol::PHANTOM) {
 				$contact["about"] = $user->description;
 				GContact::update($contact);
 			}
diff --git a/src/Worker/GProbe.php b/src/Worker/GProbe.php
index dfe309cf6..116ca2070 100644
--- a/src/Worker/GProbe.php
+++ b/src/Worker/GProbe.php
@@ -6,6 +6,7 @@
 namespace Friendica\Worker;
 
 use Friendica\Core\Cache;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\GContact;
 use Friendica\Network\Probe;
@@ -31,7 +32,7 @@ class GProbe {
 
 			$result = Cache::get("gprobe:".$urlparts["host"]);
 			if (!is_null($result)) {
-				if (in_array($result["network"], [NETWORK_FEED, NETWORK_PHANTOM])) {
+				if (in_array($result["network"], [Protocol::FEED, Protocol::PHANTOM])) {
 					logger("DDoS attempt detected for ".$urlparts["host"]." by ".$_SERVER["REMOTE_ADDR"].". server data: ".print_r($_SERVER, true), LOGGER_DEBUG);
 					return;
 				}
@@ -43,7 +44,7 @@ class GProbe {
 				Cache::set("gprobe:".$urlparts["host"], $arr);
 			}
 
-			if (!in_array($arr["network"], [NETWORK_FEED, NETWORK_PHANTOM])) {
+			if (!in_array($arr["network"], [Protocol::FEED, Protocol::PHANTOM])) {
 				GContact::update($arr);
 			}
 
@@ -54,7 +55,7 @@ class GProbe {
 		}
 		if (DBA::isResult($r)) {
 			// Check for accessibility and do a poco discovery
-			if (PortableContact::lastUpdated($r[0]['url'], true) && ($r[0]["network"] == NETWORK_DFRN)) {
+			if (PortableContact::lastUpdated($r[0]['url'], true) && ($r[0]["network"] == Protocol::DFRN)) {
 				PortableContact::loadWorker(0, 0, $r[0]['id'], str_replace('/profile/', '/poco/', $r[0]['url']));
 			}
 		}
diff --git a/src/Worker/Notifier.php b/src/Worker/Notifier.php
index a1ac09411..401178ec2 100644
--- a/src/Worker/Notifier.php
+++ b/src/Worker/Notifier.php
@@ -7,6 +7,7 @@ namespace Friendica\Worker;
 use Friendica\BaseObject;
 use Friendica\Core\Addon;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -103,7 +104,7 @@ class Notifier
 			$uid = $item_id;
 
 			$recipients_relocate = q("SELECT * FROM `contact` WHERE `uid` = %d AND NOT `self` AND `network` IN ('%s', '%s')",
-						intval($uid), NETWORK_DFRN, NETWORK_DIASPORA);
+						intval($uid), Protocol::DFRN, Protocol::DIASPORA);
 		} else {
 			// find ancestors
 			$condition = ['id' => $item_id, 'visible' => true, 'moderated' => false];
@@ -250,15 +251,15 @@ class Notifier
 						$target_item['deny_cid'].$target_item['deny_gid']) == 0))
 					$push_notify = true;
 
-				if (($thr_parent && ($thr_parent['network'] == NETWORK_OSTATUS)) || ($parent['network'] == NETWORK_OSTATUS)) {
+				if (($thr_parent && ($thr_parent['network'] == Protocol::OSTATUS)) || ($parent['network'] == Protocol::OSTATUS)) {
 					$push_notify = true;
 
-					if ($parent["network"] == NETWORK_OSTATUS) {
+					if ($parent["network"] == Protocol::OSTATUS) {
 						// Distribute the message to the DFRN contacts as if this wasn't a followup since OStatus can't relay comments
 						// Currently it is work at progress
 						$r = q("SELECT `id` FROM `contact` WHERE `uid` = %d AND `network` = '%s' AND NOT `blocked` AND NOT `pending` AND NOT `archive`",
 							intval($uid),
-							DBA::escape(NETWORK_DFRN)
+							DBA::escape(Protocol::DFRN)
 						);
 						if (DBA::isResult($r)) {
 							foreach ($r as $rr) {
@@ -336,7 +337,7 @@ class Notifier
 
 			// If the thread parent is OStatus then do some magic to distribute the messages.
 			// We have not only to look at the parent, since it could be a Friendica thread.
-			if (($thr_parent && ($thr_parent['network'] == NETWORK_OSTATUS)) || ($parent['network'] == NETWORK_OSTATUS)) {
+			if (($thr_parent && ($thr_parent['network'] == Protocol::OSTATUS)) || ($parent['network'] == Protocol::OSTATUS)) {
 				$diaspora_delivery = false;
 
 				logger('Some parent is OStatus for '.$target_item["guid"]." - Author: ".$thr_parent['author-id']." - Owner: ".$thr_parent['owner-id'], LOGGER_DEBUG);
@@ -370,9 +371,9 @@ class Notifier
 				}
 
 				// It only makes sense to distribute answers to OStatus messages to Friendica and OStatus - but not Diaspora
-				$networks = [NETWORK_OSTATUS, NETWORK_DFRN];
+				$networks = [Protocol::OSTATUS, Protocol::DFRN];
 			} else {
-				$networks = [NETWORK_OSTATUS, NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_MAIL];
+				$networks = [Protocol::OSTATUS, Protocol::DFRN, Protocol::DIASPORA, Protocol::MAIL];
 			}
 		} else {
 			$public_message = false;
@@ -385,7 +386,7 @@ class Notifier
 				&& intval($target_item['pubmail'])) {
 				$r = q("SELECT `id` FROM `contact` WHERE `uid` = %d AND `network` = '%s'",
 					intval($uid),
-					DBA::escape(NETWORK_MAIL)
+					DBA::escape(Protocol::MAIL)
 				);
 				if (DBA::isResult($r)) {
 					foreach ($r as $rr) {
@@ -440,7 +441,7 @@ class Notifier
 				$r1 = q("SELECT `batch`, ANY_VALUE(`id`) AS `id`, ANY_VALUE(`name`) AS `name`, ANY_VALUE(`network`) AS `network`
 					FROM `contact` WHERE `network` = '%s' AND `batch` != ''
 					AND `uid` = %d AND `rel` != %d AND NOT `blocked` AND NOT `pending` AND NOT `archive` GROUP BY `batch`",
-					DBA::escape(NETWORK_DIASPORA),
+					DBA::escape(Protocol::DIASPORA),
 					intval($owner['uid']),
 					intval(Contact::SHARING)
 				);
@@ -455,7 +456,7 @@ class Notifier
 				}
 			}
 
-			$condition = ['network' => NETWORK_DFRN, 'uid' => $owner['uid'], 'blocked' => false,
+			$condition = ['network' => Protocol::DFRN, 'uid' => $owner['uid'], 'blocked' => false,
 				'pending' => false, 'archive' => false, 'rel' => [Contact::FOLLOWER, Contact::FRIEND]];
 
 			$r2 = DBA::toArray(DBA::select('contact', ['id', 'name', 'network'], $condition));
@@ -469,7 +470,7 @@ class Notifier
 					// except for Diaspora batch jobs
 					// Don't deliver to folks who have already been delivered to
 
-					if (($rr['network'] !== NETWORK_DIASPORA) && (in_array($rr['id'], $conversants))) {
+					if (($rr['network'] !== Protocol::DIASPORA) && (in_array($rr['id'], $conversants))) {
 						logger('notifier: already delivered id=' . $rr['id']);
 						continue;
 					}
diff --git a/src/Worker/OnePoll.php b/src/Worker/OnePoll.php
index b3af0b701..7f60ddc56 100644
--- a/src/Worker/OnePoll.php
+++ b/src/Worker/OnePoll.php
@@ -8,6 +8,7 @@ use Friendica\BaseObject;
 use Friendica\Content\Text\BBCode;
 use Friendica\Core\Config;
 use Friendica\Core\PConfig;
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
 use Friendica\Model\Item;
@@ -68,7 +69,7 @@ class OnePoll
 		}
 
 		// Diaspora users, archived users and followers are only checked if they still exist.
-		if ($contact['archive'] || ($contact["network"] == NETWORK_DIASPORA) || ($contact["rel"] == Contact::FOLLOWER)) {
+		if ($contact['archive'] || ($contact["network"] == Protocol::DIASPORA) || ($contact["rel"] == Contact::FOLLOWER)) {
 			$last_updated = PortableContact::lastUpdated($contact["url"], true);
 			$updated = DateTimeFormat::utcNow();
 
@@ -114,7 +115,7 @@ class OnePoll
 		);
 
 		// Update the contact entry
-		if (($contact['network'] === NETWORK_OSTATUS) || ($contact['network'] === NETWORK_DIASPORA) || ($contact['network'] === NETWORK_DFRN)) {
+		if (($contact['network'] === Protocol::OSTATUS) || ($contact['network'] === Protocol::DIASPORA) || ($contact['network'] === Protocol::DFRN)) {
 			if (!PortableContact::reachable($contact['url'])) {
 				logger("Skipping probably dead contact ".$contact['url']);
 
@@ -160,7 +161,7 @@ class OnePoll
 
 		logger("poll: ({$contact['network']}-{$contact['id']}) IMPORTER: {$importer['name']}, CONTACT: {$contact['name']}");
 
-		if ($contact['network'] === NETWORK_DFRN) {
+		if ($contact['network'] === Protocol::DFRN) {
 			$idtosend = $orig_id = (($contact['dfrn-id']) ? $contact['dfrn-id'] : $contact['issued-id']);
 			if (intval($contact['duplex']) && $contact['dfrn-id']) {
 				$idtosend = '0:' . $orig_id;
@@ -289,9 +290,9 @@ class OnePoll
 
 			$xml = Network::post($contact['poll'], $postvars);
 
-		} elseif (($contact['network'] === NETWORK_OSTATUS)
-			|| ($contact['network'] === NETWORK_DIASPORA)
-			|| ($contact['network'] === NETWORK_FEED)) {
+		} elseif (($contact['network'] === Protocol::OSTATUS)
+			|| ($contact['network'] === Protocol::DIASPORA)
+			|| ($contact['network'] === Protocol::FEED)) {
 
 			// Upgrading DB fields from an older Friendica version
 			// Will only do this once per notify-enabled OStatus contact
@@ -300,7 +301,7 @@ class OnePoll
 			$stat_writeable = ((($contact['notify']) && ($contact['rel'] == Contact::FOLLOWER || $contact['rel'] == Contact::FRIEND)) ? 1 : 0);
 
 			// Contacts from OStatus are always writable
-			if ($contact['network'] === NETWORK_OSTATUS) {
+			if ($contact['network'] === Protocol::OSTATUS) {
 				$stat_writeable = 1;
 			}
 
@@ -330,7 +331,7 @@ class OnePoll
 
 			$xml = $ret['body'];
 
-		} elseif ($contact['network'] === NETWORK_MAIL) {
+		} elseif ($contact['network'] === Protocol::MAIL) {
 			logger("Mail: Fetching for ".$contact['addr'], LOGGER_DEBUG);
 
 			$mail_disabled = ((function_exists('imap_open') && (! Config::get('system', 'imap_disabled'))) ? 0 : 1);
@@ -383,7 +384,7 @@ class OnePoll
 							$datarray = [];
 							$datarray['verb'] = ACTIVITY_POST;
 							$datarray['object-type'] = ACTIVITY_OBJ_NOTE;
-							$datarray['network'] = NETWORK_MAIL;
+							$datarray['network'] = Protocol::MAIL;
 							// $meta = Email::messageMeta($mbox, $msg_uid);
 
 							$datarray['uri'] = Email::msgid2iri(trim($meta->message_id, '<>'));
@@ -472,7 +473,7 @@ class OnePoll
 
 							// If it seems to be a reply but a header couldn't be found take the last message with matching subject
 							if (empty($datarray['parent-uri']) && $reply) {
-								$condition = ['title' => $datarray['title'], 'uid' => importer_uid, 'network' => NETWORK_MAIL];
+								$condition = ['title' => $datarray['title'], 'uid' => importer_uid, 'network' => Protocol::MAIL];
 								$params = ['order' => ['created' => true]];
 								$parent = Item::selectFirst(['parent-uri'], $condition, $params);
 								if (DBA::isResult($parent)) {
@@ -529,7 +530,7 @@ class OnePoll
 							if ($datarray['parent-uri'] === $datarray['uri']) {
 								$datarray['private'] = 1;
 							}
-							if (($contact['network'] === NETWORK_MAIL) && (!PConfig::get($importer_uid, 'system', 'allow_public_email_replies'))) {
+							if (($contact['network'] === Protocol::MAIL) && (!PConfig::get($importer_uid, 'system', 'allow_public_email_replies'))) {
 								$datarray['private'] = 1;
 								$datarray['allow_cid'] = '<' . $contact['id'] . '>';
 							}
@@ -584,16 +585,16 @@ class OnePoll
 			consume_feed($xml, $importer, $contact, $hub);
 
 			// do it a second time for DFRN so that any children find their parents.
-			if ($contact['network'] === NETWORK_DFRN) {
+			if ($contact['network'] === Protocol::DFRN) {
 				consume_feed($xml, $importer, $contact, $hub);
 			}
 
 			$hubmode = 'subscribe';
-			if ($contact['network'] === NETWORK_DFRN || $contact['blocked']) {
+			if ($contact['network'] === Protocol::DFRN || $contact['blocked']) {
 				$hubmode = 'unsubscribe';
 			}
 
-			if (($contact['network'] === NETWORK_OSTATUS ||  $contact['network'] == NETWORK_FEED) && (! $contact['hub-verify'])) {
+			if (($contact['network'] === Protocol::OSTATUS ||  $contact['network'] == Protocol::FEED) && (! $contact['hub-verify'])) {
 				$hub_update = true;
 			}
 
@@ -603,7 +604,7 @@ class OnePoll
 
 			logger("Contact ".$contact['id']." returned hub: ".$hub." Network: ".$contact['network']." Relation: ".$contact['rel']." Update: ".$hub_update);
 
-			if (strlen($hub) && $hub_update && (($contact['rel'] != Contact::FOLLOWER) || $contact['network'] == NETWORK_FEED)) {
+			if (strlen($hub) && $hub_update && (($contact['rel'] != Contact::FOLLOWER) || $contact['network'] == Protocol::FEED)) {
 				logger('hub ' . $hubmode . ' : ' . $hub . ' contact name : ' . $contact['name'] . ' local user : ' . $importer['name']);
 				$hubs = explode(',', $hub);
 				if (count($hubs)) {
@@ -622,7 +623,7 @@ class OnePoll
 			self::updateContact($contact, ['last-update' => $updated, 'success_update' => $updated]);
 			DBA::update('gcontact', ['last_contact' => $updated], ['nurl' => $contact['nurl']]);
 			Contact::unmarkForArchival($contact);
-		} elseif (in_array($contact["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS, NETWORK_FEED])) {
+		} elseif (in_array($contact["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS, Protocol::FEED])) {
 			$updated = DateTimeFormat::utcNow();
 
 			self::updateContact($contact, ['last-update' => $updated, 'failure_update' => $updated]);
diff --git a/src/Worker/Queue.php b/src/Worker/Queue.php
index 375267aae..b27a776c7 100644
--- a/src/Worker/Queue.php
+++ b/src/Worker/Queue.php
@@ -7,6 +7,7 @@ namespace Friendica\Worker;
 use Friendica\Core\Addon;
 use Friendica\Core\Cache;
 use Friendica\Core\Config;
+use Friendica\Core\Protocol;
 use Friendica\Core\Worker;
 use Friendica\Database\DBA;
 use Friendica\Model\Contact;
@@ -110,7 +111,7 @@ class Queue
 		$deliver_status = 0;
 
 		switch ($contact['network']) {
-			case NETWORK_DFRN:
+			case Protocol::DFRN:
 				logger('queue: dfrndelivery: item ' . $q_item['id'] . ' for ' . $contact['name'] . ' <' . $contact['url'] . '>');
 				$deliver_status = DFRN::deliver($owner, $contact, $data);
 
@@ -121,7 +122,8 @@ class Queue
 					Cache::set($cachekey_deadguy . $contact['notify'], true, CACHE_MINUTE);
 				}
 				break;
-			case NETWORK_OSTATUS:
+
+			case Protocol::OSTATUS:
 				logger('queue: slapdelivery: item ' . $q_item['id'] . ' for ' . $contact['name'] . ' <' . $contact['url'] . '>');
 				$deliver_status = Salmon::slapper($owner, $contact['notify'], $data);
 
@@ -132,7 +134,8 @@ class Queue
 					QueueModel::removeItem($q_item['id']);
 				}
 				break;
-			case NETWORK_DIASPORA:
+
+			case Protocol::DIASPORA:
 				logger('queue: diaspora_delivery: item ' . $q_item['id'] . ' for ' . $contact['name'] . ' <' . $contact['url'] . '>');
 				$deliver_status = Diaspora::transmit($owner, $contact, $data, $public, true, 'Queue:' . $q_item['id'], true);
 
diff --git a/src/Worker/UpdateGContact.php b/src/Worker/UpdateGContact.php
index 55c91a127..f2919e4a7 100644
--- a/src/Worker/UpdateGContact.php
+++ b/src/Worker/UpdateGContact.php
@@ -6,6 +6,7 @@
 
 namespace Friendica\Worker;
 
+use Friendica\Core\Protocol;
 use Friendica\Database\DBA;
 use Friendica\Network\Probe;
 use Friendica\Protocol\PortableContact;
@@ -28,13 +29,13 @@ class UpdateGContact
 			return;
 		}
 
-		if (!in_array($r[0]["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])) {
+		if (!in_array($r[0]["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])) {
 			return;
 		}
 
 		$data = Probe::uri($r[0]["url"]);
 
-		if (!in_array($data["network"], [NETWORK_DFRN, NETWORK_DIASPORA, NETWORK_OSTATUS])) {
+		if (!in_array($data["network"], [Protocol::DFRN, Protocol::DIASPORA, Protocol::OSTATUS])) {
 			if ($r[0]["server_url"] != "") {
 				PortableContact::checkServer($r[0]["server_url"], $r[0]["network"]);
 			}