DCCP is a new transport protocol being developed by the IETF to provide a connection-oriented, congestion controlled, unreliable transport service. Most applications that require an unreliable transport currently use UDP and ignore congestion issues, causing concerns about congestion collapse in the general Internet if these applications (especially VoIP) get too popular. DCCP is meant to give these applications an opportunity to become good 'Net citizens without forcing them to individually tackle the difficult problems of developing congestion control mechanisms.
This is the DCCP-TP Wiki. DCCP-TP is a fresh-start implementation of the Datagram Congestion Control Protocol (DCCP) optimized for portability. This site provides source code downloads and documentation for DCCP-TP.
The Datagram Congestion Control Protocol (DCCP) is a transport protocol that provides bidirectional unicast connections of congestion-controlled unreliable datagrams. DCCP is suitable for applications that transfer fairly large amounts of data and that can benefit from control over the tradeoff between timeliness and reliability.