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PSYC (Protocol for SYnchronous Conferencing) is a flexible text-based protocol for conferencing. Messages are delivered via multicast or unicast. Currently PSYC is mostly used for chatrooms, presence awareness, friendcasting, newscasting based on a decentral social network, but is build to be extensible for telephony or videostreaming. The strength of PSYC is in its use as a interserver protocol.


The protocol is based on an open and decentral network. Everyone can setup his own server and provide hosting for identities and services. A service is connected to an identity via rooms or channels. Compared to IRC-Channels the PSYC-Channels are fully programmable. They can act like an IRC-Channel, but it has also the possibility to deliver a rss feed via server push, act as an dictionary interface, stream binary data such as shared files or video streams.

PSYC uses like Jabber URIs as network identification. The protocol itself is oriented on RFC822 and not on XML.

Protocol Example

Initialisation Packet in PSYC as described in the PSYC Wiki:

=_source        psyc://
=_target        psyc://ente.aquarium:-32872

:_using_protocols       PSYC/0.9 TCP IP/4
:_understand_protocols  PSYC/0.9 TCP IP/4, PSYC/0.9 UDP IP/4, IRC/2, Jabber, Chatlet, Telnet, HTTP/1.0, WAP
:_understand_modules    _context
:       _encrypt
:_use_modules           _context
:_implementation        psycMUVE/0.99 LDMUD/3.3.683 Linux i686
=_encoding              ISO-8859-1
Connection to [_source] established.
Protocols accepted: [_understand_protocols].





The idea of PSYC was first written down in 1995. In productive use are some incomplete Versions since 1997. The reference implementation psyced is ready to use since 2005.


  • since 2003 used for the hosted backstage video chat show of the MTV Europe Movie Awards.
  • used from the german service provider T-Online as chat backend
  • used from Magix as messaging backend in software products