Selectively Reliable Multicast Protocol (SRMP)
John Mark Pullen, Fei Zhao, Danny Cohen · RFC · 2006
The Selectively Reliable Multicast Protocol (SRMP) is a transport protocol, intended to deliver a mix of reliable and best-effort messages in an any-to-any multicast environment, where the best- effort traffic occurs in significantly greater volume than the best- effort traffic and therefore can be used to carry sequence numbers of reliable messages for loss detection. SRMP is intended for use in a distributed simulation application environment, where only the latest value of reliable transmission for any particular data identifier requires delivery. SRMP has two sublayers: a bundling sublayer that combines short messages, peforms NAK suppression, and incorporates the TCP-Friendly Multicast Congestion Control of Widmer and Handley, dropping best- effort traffic in order to achieve congestion control; and a selectively reliable transport (SRT) sublayer that formats best- effort and reliable transmissions and also creates negative acknowledgements when loss of reliable messages is detected.