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setup QOS for Voice on a Frame Relay using 1720 routers

We have 4 locations using a Frame Relay for Data and Voice. Some of the voice connections are breaking up when data is used on the network. We would like to setup QOS so that voice will take priority over the data.

Here is one of the config of the primary frame router.

Using 1416 out of 29688 bytes
!
version 12.2
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname Melbourne_Frame
!
enable secret 5 $1$qMzC$AZHr2Ylgrgx1O2dx5SnXA.
enable password 7 05080F1C22431F
!
ip subnet-zero
ip name-server 12.127.17.71
!
!
!
!
!
interface FastEthernet0/0
description Melbourne LAN
ip address 192.168.2.2 255.255.255.0
speed auto
!
interface Serial0/0
no ip address
encapsulation frame-relay
service-module t1 timeslots 1-12
frame-relay lmi-type ansi
!
interface Serial0/0.1 point-to-point
description Rogers, AR
ip address 10.254.254.1 255.255.255.252
frame-relay interface-dlci 102
!
interface Serial0/0.2 point-to-point
description Manchester, NH
ip address 10.254.254.5 255.255.255.252
frame-relay interface-dlci 101
!
interface Serial0/0.3 point-to-point
description Boucherville, CA
ip address 10.254.254.13 255.255.255.252
frame-relay interface-dlci 105
!
interface Serial0/0.4 point-to-point
description Three Rivers, CA
ip address 10.254.254.9 255.255.255.252
frame-relay interface-dlci 103
!
router eigrp 100
network 10.1.1.0 0.0.0.255
network 10.254.254.0 0.0.0.255
network 192.168.2.0
no auto-summary
no eigrp log-neighbor-changes
!
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.2.1 200
no ip http server
!
!
!
line con 0
line aux 0
line vty 0 4
password 7 1513080D507B78650870
login
!
no scheduler allocate
end

pedrow

I've used priority queueing successfully for VOIP in the past. You can either do it by source/destination if your VOIP stuff has dedicated netblocks or by source/dest ports if you know the protocols used.

Here's an example:

interface Serial2/0/0
ip address xxxxxxxxxxxx 255.255.255.252
no fair-queue
priority-group 10
!
priority-list 10 protocol ip high list 113
!
access-list 113 permit tcp 172.16.255.0 0.0.0.255 range 3200 3201 172.16.255.0 0.0.0.255 range 3200 3201
access-list 113 permit tcp 172.16.255.0 0.0.0.255 range 3200 3201 172.24.1.80 0.0.0.15 range 3200 3201

So, in this example, I knew the source-dest pairs and the protocol ranges. These packets got tagged as 'high' priority. All else got tagged as normal.

Lots of good QOS info and possibilities can be read about here if you don't think QOS is your best option:
http://www.cisco.com/en/US/products/sw/iosswrel/ps5187/prod_configuration_guide09186a008017d8e5.html

i.e. you can try things like traffic shaping, rate limiting, etc, but it still comes down to you being able to sift out the VOIP traffic from the rest of it.

Hope this helps.

Les Moore

Here's another example of LLQ / traffic-shaping that works pretty well...

!
class-map match-all bts
match access-group 101
!
!
policy-map TEST
class bts
priority 64
class class-default
fair-queue
!
!
interface Serial0/0
description LINK TO FRAME-CIRCUIT
bandwidth 512
no ip address
encapsulation frame-relay
ip route-cache flow
no ip mroute-cache
frame-relay traffic-shaping
frame-relay lmi-type ansi
!
interface Serial0/0.1 point-to-point
description *remote*
bandwidth 256
ip address 192.168.254.1 255.255.255.0
no cdp enable
frame-relay interface-dlci 31 IETF
class voip
!
!
map-class frame-relay voip
frame-relay cir 256000
frame-relay bc 2560
frame-relay be 0
frame-relay mincir 256000
frame-relay fragment 320
service-policy output TEST
!
access-list 101 remark VOIP to *remote*
access-list 101 permit ip host 172.18.91.240 host 172.18.92.240
access-list 101 permit ip host 172.18.91.241 host 172.18.92.241
!

Reference:
http://www.cisco.com/en/US/tech/tk652/tk698/technologies_configuration_example09186a0080094af9.shtml

ASKER CERTIFIED SOLUTION

Les Moore

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