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Frame Relay Traffic Shaping Configuration 273
There are no configurable options; you simply issue the command. Use this command over the
frame-relay traffic-rate command whenever possible. In addition, note that the frame-relay
adaptive-shaping becn
command makes the frame-relay becn-response-enable command
obsolete.
The preceding commands have not addressed the issues of defining CIR, Bc, Be, and MinCIR.
As you could probably guess, each parameter has an associated command. The command
structure for the frame-relay cir command for the map class is as follows:
RouterA(config-map-class)#frame-relay cir [in
| out] bits
The rate in the frame-relay cir command is expressed in bps and should be the rate at which
transmission should be sent in periods with no congestion.
Use the frame-relay bc command to define the committed burst size for the map class:
RouterA(config-map-class)#frame-relay bc [in
| out] bits
The Bc is the amount to be transmitted per interval in bytes (usually CIR
ч 8).
Use the frame-relay be command to define excessive burst for a map class:
RouterA(config-map-class)#frame-relay be [in
| out] bits
The Be is the additional amount to be sent in the first interval. If CIR = port speed, set Be to 0
because no additional bandwidth is available for a burst.
Use the frame-relay mincir command to specify the MinCIR for the map class:
RouterA(config-map-class)#frame-relay mincir [in
| out] bits
Note that the MinCIR in this command is the CIR that was negotiated with the telco. It is
usually one-half the actual CIR.
Example 9-8 brings it all together in a configuration that implements all the commands.
Example 9-8
Frame Relay Traffic Shaping
RouterA(config)#map-class frame-relay EM&AM
RouterA(config-map-class)#frame-relay adaptive-shaping becn
RouterA(config-map-class)#frame-relay cir 128000
RouterA(config-map-class)#frame-relay bc 16000
RouterA(config-map-class)#frame-relay be 0
RouterA(config-map-class)#frame-relay mincir 64000
RouterA(config-map-class)#exit
RouterA(config)#interface serial 0
RouterA(config-if)#encapsulation frame-relay
RouterA(config-if)#frame-relay traffic-shaping
RouterA(config-if)#interface serial 0.1 point-to-point
RouterA(config-subif)#ip address 10.1.1.1 255.255.255.0
RouterA(config-subif)#frame-relay interface-dlci 16
RouterA(config-fr-dlci)#class EM&AM