Frame relay traffic shaping regulates the outgoing traffic rate on a per-DLCI basis. Each DLCI maintains a weighted fair VoIP queue scheduler to buffer the packets.
FRF.12 fragmentation allows for link fragmentation and interleaving (LFI), which reduces the serialization delay on narrow bandwidth PVCs. This is required for VoIP traffic.
You can configure the traffic shaping and fragmentation parameters within traffic shaping templates called map classes. A map class is comprised of the following parameters:
CIR. Default = 56,000 bps
Committed Burst (BC) size. Default =7,000 bits
Excess Burst (BE) size. Default = 0 bits
Fragmentation. Fragment size, in bytes. Default = No Fragmentation.
You can configure up to 128 different map classes using different combinations of traffic shaping parameters. You then apply these map classes to a PVC.
Note:
For a Priority DLCI group you must configure the Primary VC before associating a DLCI map class to the Priority DLCI group VCs. Removing the Primary VC after associating a DLCI map class to the Priority LCI group VCs, removes their map class configuration.
You can enable traffic shaping on a frame relay interface with the frame-relay traffic-shaping command. After you enable traffic shaping, a default map class is applied to all currently configured PVCs.
