Enterasys Networks X-Pedition XSR CLI - Manual (Page 422)

Frame Relay Map Class Commands
9-98 Configuring Frame Relay
Example
This example adds map class slowlink with Be of 10000 and Bc of 6000 bits:
XSR(config)#map-class frame-relay slowlink
XSR(config-map-class<slowlink>)#frame-relay be out 10000
XSR(config-map-class<slowlink>)#frame-relay bc out 6000
frame-relay cir
This command specifies the outgoing Committed Information Rate (CIR) for a Frame Relay map‐
class. CIR, Bc and Be values specify how the XSR forwards packets under normal and congested
conditions using the following equation:
Tc = Bc/CIR = 7,000 bits / 56,000 bps = 125 mS (Bc and CIR values are default)
Frame Relay networks are committed to deliver Bc bits of data every Tc, so maximum committed
throughput equals 7,000/125mS = 56kbps = CIR. In this sense, Committed Burst (Bc) is not really a
burst but a “smoothing” function for the number of bits that the XSR is allowed to transmit during
the Tc period in order to achieve the specified CIR.
Since the maximum number of bits that can be sent during Tc is Bc plus Be bits, using the default
values, maximum throughput equals (Bc + Be)/Tc = (7,000 + 7,000)/125mS = 112kbps = 2 * 56kbps =
2 * CIR.
Syntax
frame-relay cir out rate
Syntax of the “no” Form
The no command resets the CIR to its default value:
no frame-relay cir out
Mode
Map Class configuration: XSR(config-map-class)#
Defaults
• CIR enforced for outgoing traffic only
• CIR: 56000 bps
• Be: 7000 bits
• Bc: 7000 bits
Example
This example creates the map class slowlink with cir set at 9600 bps:
XSR(config)#map-class frame-relay slowlink
XSR(config-map-class<slowlink>)#frame-relay cir out 9600
out Sets the traffic direction ‐ output rate limiting only.
rate CIR, ranging from 1000 to 1,000,000 bits per second.