R2511-HP MSR Router Series ACL and QoS Command Reference(V5)

145
Usage guidelines
CIR is the minimum transmit rate that a PVC can provide. When congestion occurs to the network, the
user can still send data at the rate of CIR.
When congestion occurs to the network, DCE sends packets with the BECN flag bit 1 to DTE. On
receiving the packets, DTE gradually decreases the transmit rate of PVCs from CIR ALLOW to CIR. If DTE
receives no packets with the BECN flag bit 1 within 125 ms, DTE restores the transmit rate of PVCs to CIR
ALLOW.
CIR must be equal to or lower than CIR ALLOW.
Examples
# Set the minimum CIR to 32000 bps for the FR class test1.
<Sysname> system-view
[Sysname] fr class test1
[Sysname-fr-class-test1] cir 32000
Related commands
• cbs
• ebs
• cir allow
cir allow
Use cir allow to set the CIR ALLOW for FR PVCs.
Use undo cir allow to restore the default.
Syntax
cir allow [ inbound | outbound ] committed-information-rate
undo cir allow [ inbound | outbound ]
Views
FR class view
Default command level
2: System level
Parameters
inbound: Sets the CIR ALLOW for the incoming packets. This argument is available when FR traffic
policing is enabled on interfaces.
outbound: Sets the CIR ALLOW for the outgoing packets. This argument is available when FR traffic
policing is enabled on interfaces.
committed-information-rate: CIR ALLOW in the range of 1000 to 45000000 bps. The CIR ALLOW is
56000 bps by default.
Usage guidelines
CIR ALLOW is the transmit rate that an FR PVC can provide when no congestion occurs to the network.
If the packet direction is not specified, the CIR ALLOW is effective for both incoming packets and
outgoing packets.
CIR ALLOW must be greater than CIR.