Cisco Frame-Relay Traffic Shaping Configuration Example

We will test Cisco Frame-Relay Traffic Shaping.

LLQ (low latency queueing) will be used for traffic shapping queues.LLQ will provide prioritization of voip packets:

Configuration of R1:

class-map match-all voip
 match  dscp ef
!
!
policy-map LLQ-Test
 class voip
  priority percent 50
 class class-default
  fair-queue

interface Serial0/0
 no ip address
 encapsulation frame-relay
 no fair-queue
 frame-relay traffic-shaping
!
interface Serial0/0.1 point-to-point
 ip address 10.10.10.1 255.255.255.252
 snmp trap link-status
 frame-relay interface-dlci 100
  class FRTS-Test 
!
map-class frame-relay FRTS-Test
 frame-relay cir 256000
 service-policy output LLQ-Test

Configuration of R2

class-map match-all voip
 match  dscp ef
!
policy-map LLQ-Test
 class voip
  priority percent 50
 class class-default
  fair-queue

interface Serial0/0
 no ip address
 encapsulation frame-relay
 no fair-queue
 frame-relay traffic-shaping
!
interface Serial0/0.1 point-to-point
 ip address 10.10.10.2 255.255.255.252
 snmp trap link-status
 frame-relay interface-dlci 100 
  class FRTS-Test
!
map-class frame-relay FRTS-Test
 frame-relay cir 256000
 service-policy output LLQ-Test

Lets test prioritization of voip traffic by marking icmp packets to ef value( tos 184):

R2#ping                           
Protocol [ip]:
Target IP address: 10.10.10.1
Repeat count [5]: 100
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: yes
Source address or interface:
Type of service [0]: 184
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 100, 100-byte ICMP Echos to 10.10.10.1, timeout is 2 seconds:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Success rate is 100 percent (100/100), round-trip min/avg/max = 10/82/186 ms

At the same time we had great amount of best-effort traffic:

R2#show policy-map interface s0/0.1

 Serial0/0.1: DLCI 100 -
  Service-policy output: LLQ-Test
    Class-map: voip (match-all)
      200 packets, 20800 bytes
      5 minute offered rate 8000 bps, drop rate 0 bps
      Match:  dscp ef (46)
      Queueing
        Strict Priority
        Output Queue: Conversation 24
        Bandwidth 50 (%)
        Bandwidth 64 (kbps) Burst 1600 (Bytes)
        (pkts matched/bytes matched) 102/10608
        (total drops/bytes drops) 0/0
    Class-map: class-default (match-any)
      50680 packets, 71151483 bytes
      5 minute offered rate 1601000 bps, drop rate 1489000 bps      Match: any
      Queueing
        Flow Based Fair Queueing
        Maximum Number of Hashed Queues 16
        (total queued/total drops/no-buffer drops) 0/46962/0

We see that, voip packets passed without any drop, but best effort traffic dropped.