FR congestion management

FR congestion management can process FR packets when congestion occurs in the network. It drops the packets with the DE flag bits set to 1 and notifies other devices on the network about the congestion.

FR congestion management is applied on the outgoing interface of an FR switching device. If no congestion occurs, the FR switching device forwards the FR packets without any processing. If congestion occurs, packets with the FE flag bits set to 1 are dropped. As for forward packets to be forwarded, the FECN flag bits in the FR packet headers are set to 1. As for backward packets on the same PVC, the BECN flag bits in the FR packet headers are set to 1. If no backward packets are transmitted within a period, the device automatically transmits the packets with the BECN flag bits set to 1 to the calling DTE.