Trillian Off-the-Record is a cross-platform encryption plugin that provides Off the Record messaging support in Trillian. Unlike SecureIM, this style of encryption allows both authentication that the source of the messages is a known individual as well as plausable deniability. Messages sent during an encrypted session are secure, but messages can easily be forged after the fact, preventing them from being easily attributable to any one person.
Off-the-Record (OTR) Messaging allows you to have private conversations over instant messaging by providing: Encryption No one else can read your instant messages. Authentication You are assured the correspondent is who you think it is. Deniability The messages you send do not have digital signatures that are checkable by a third party. Anyone can forge messages after a conversation to make them look like they came from you. However, during a conversation, your correspondent is assured the messages he sees are authentic and unmodified. Perfect forward secrecy If you lose control of your private keys, no previous conversation is compromised.
Currently, Risen supports Trillian mediums for AIM, ICQ, MSN, Yahoo, Facebook Chat, Jabber, and Rendezvous instant messaging networks. More mediums will be added as their support is discovered.