http://www.rfc-editor.org/rfc/rfc4103.txt
RFC 4103: RTP Payload for Text Conversation, G. Hellstrom, P. Jones2005-06-01T23:00:00-00:00This RTP payload description recommends a method to include redundant text from already transmitted packets in order to reduce the risk of text loss caused by packet loss. [STANDARDS-TRACK]