fast retransmit and recovery (TCP/IP) (FRR)
Fast Retransmit and Recovery (FRR) is an algorithm used in TCP/ IP protocols for congestion control that can recover lost or damaged data packets in the event of packet loss.
If a receiving unit detects that a data packet is missing or damaged during normal TCP transmission, it sends a request to the sending station. At the same time, a timer is used to generate a time-out during which no further data packets can be sent. This time-out period is shortened in Fast Retransmit and Recovery (FRR) because the lost data packet is retransmitted without waiting for the time-out to end.
The FRR algorithm for fast retransmission of data packets has been described in RFC 2001 and RFC 2581.