TCP does congestion control + reliable delivery. Retransmits help reliable delivery. So, TCP without retransmits is basically a datagram protocol that does on

TCP does congestion control + reliable delivery. Retransmits help reliable delivery. So, TCP without retransmits is basically a datagram protocol that does only congestion control. DCCP does precisely this and its congestion control is TCP friendly. It's available in Linux afaik. http://en.wikipedia.org/wiki/Datagram_Congestion_Control_Protocol http://read.cs.ucla.edu/dccp/