# Used protocols ## Friendicas DFRN Protocol * [Document with the DFRN specification](spec/dfrn2.pdf) * [Schema of the contact request process](spec/dfrn2_contact_request.png) * [Schema of the contact request confirmation](spec/dfrn2_contact_confirmation.png) * [Description of the message flow](help/spec/message-flow) ## ActivityStreams Friendica is using ActivityStreams in version 1.0 for its activities and object types. Additional types are used for non standard activities. * [Link to the specification](http://activitystrea.ms/head/activity-schema.html) * [List of used ActivityStreams verbs and object types.](https://github.com/friendica/friendica/wiki/ActivityStreams) ## Portable Contacts Portable Contacts is used for friends lists. * [Link to the specification](https://web.archive.org/web/20160426223008/http://portablecontacts.net/draft-spec.html) (Link to archive.org)