Used Protocols
Friendicas DFRN Protocol
ActivityStreams
Friendica is using ActivityStreams in version 1.0 for its activities and object types. Additional types are used for non standard activities.
Salmon
Salmon is used as a message exchange protocol for replies and mentions.
Portable Contacts
Portable Contacts is used for friends lists.
- Link to the specification (Link to archive.org)
pubsubhubbub
pubsubhubbub is used for OStatus.