Abstract: A system and method for optimizing and eliminating congestion for WAN interfaces within an access domain are disclosed. In an exemplary embodiment, a message is received at an interface between a first sub-network and a second sub-network. The message corresponds to a data stream between the first and second sub-networks. Congestion at the interface between the first sub-network and the second sub-network is analyzed based on the received message and overall data rate. When the congestion at the interface exceeds a congestion threshold, the message is modified, causing the destination sub-network to alter the data stream corresponding to the message in order to reduce the congestion at the interface. The modified message is then provided to the destination sub-network. The modification to the message may include specifying the use of a half-rate codec for the data stream in order to reduce the congestion.