User`s guide

XSR User’s Guide 223
Chapter 10 Configuring QoS for Frame Relay
Configuring Quality of Service
XSR(config-cmap<class2>)#match ip precedence 2
Create the policy map:
XSR(config)#policy-map policy1
XSR(config-pmap-policy1>)#class class1
XSR(config-pmap-c<class1>)#bandwidth 200
XSR(config-pmap-c<class1>)#queue-limit 40
XSR(config-pmap<policy1>)#class class2
XSR(config-pmap-c<class2>)#bandwidth 300
XSR(config-pmap-c<class2>)#random-detect 34 56 3
XSR(config-pmap<policy1>)#class class-default
XSR(config-pmap-c<class-default>)#queue-limit 20
Apply the configuration to the interface:
XSR(config)#interface serial 1/1
XSR(config-if<S1/1>)#service-policy output policy1
Configuring QoS for Frame Relay
The following example sets Serial interface 1/1 for Frame Relay with one
DLCI (100) which will support three types of traffic: voice that is assigned to a
priority queue with a bandwidth of 20 kbps, FTP that is assigned to fair queue
with 50 percent of the remaining bandwidth, and Class1 that is assigned to
class-default (and gets the other 50 percent). DLCI 100 sets CIR at 64 kbps (the
sum of all PQs and classes should not exceed the CIR of the DLCI).
When the connection is congested, priority traffic will get its bandwidth share
(smaller than the DLCI CIR) while all other classes share the remaining
bandwidth proportional to what was requested. Voice is rate limited to
20 Kbps and the interval over which it is enforced is equivalent to
burst/bandwidth size (2500 bytes/20 Kbps).
If no burst size is set, default burst size is used. Packets exceeding 20 Kbps are
dropped. Class1 and FTP are served after voice gets its share, but split the
remaining bandwidth equally.