TCP Instant Recovery: Incorporating Forward Error Correction in TCP

Ordinary TCP loss recovery takes at least one round-trip time and as such can increase application-perceived latency, especially for short flows such as Web transactions. TCP Instant Recovery (TCP-IR) is an experimental algorithm that allows a receiving end to recover lost packets without retransmissions, thus potentially saving at least one full round-trip time compared to standard TCP. TCP-IR achieves this by judiciously injecting encoded data segments within a TCP stream. This document describes the TCP-IR algorithm at the sending and receiving ends, along with the required protocol changes.