4. Congestion control with DCCP

A congestion control (CC) mechanism consists essentially of a flow control algorithm implemented by the sender, and a feedback mechanism (ACKs, etc.) by the receiver.

In DCCP, CC methods are identified by a one-byte code, known as CCID (Congestion control ID ). This coding allows DCCP to support around 256 different congestion control mechanisms. Two methods have already been standardized: TCP-like flow control and TCP-Friendly Rate Control (TFRC).