VOIP call breaking and echo

[fmatrine]

Dear Sir,

We have a wan network with 1 central location and multiple remote locations.

At central location we have cisco 3745 router with channelized E1 line and all the remote locations are using cisco 1751-v router for connecting to central location over 64kbps leased line.

Applications used over the wan network are both voice (VOIP) and data (SAP) applications.

At times we are facing problems of voice call breaking and echo.

We need to do some prioritization of voice to improve it kindly suggest with config required at central and remote router to acheive uniteruppted voice/data communication over the wan.

Pls advice

regards

Deepak.

[generalee]

Check that regions are set to G.711 in CCM, and that on the router has input and output attenuation at or around 6 and -9? I can check on this on Tuesday of next week for the input and output on the router for you if you want. I have pretty much successfully eliminated call breaking up and echo.

[fmatrine]

Dear Sir,

For updating u with our setup, we are not using cisco CCM.We are using router based VOIP and Data over WAN.

For acheciving this we are using cisco 3745 with NM-HDV-E1 at central site.

At all other remote locations we are using cisco 1751-V router with VIC-2FXS card for VOIP setup

At central site we are having channelized E1 line (2Mbps).

At all other remote location we are using 64Kbps leased Line for connectivity to the central site.

Also we are using G.729 codec in router and not G.711 because of limited bandwidth available .... as G.711 uses more bandwidth than G.729..

Pls advice how can i improve voice call quality.

Regards

Deepak

[spremkumar]

Hi deepak

Wht i suggest is u can try out giving priority to VOIP traffic rather than SAP when VOIP being used and when not used SAP should be able to use the full avl bandwidth.

just try this config out ..

class-map match-any voice-traffic

match ip precedence 5

match access-group 102

policy-map voice-policy

class voice-traffic

priority 46

class class-default

fair-queue

access-list 102 permit udp any any range 16384 32767

int ser 0/0

service-policy output voice-policy

u shuld configure the same on both the endpoints i.e.,on both ur remote and ur central router

the same we tried sometime back and it worked fine.

regds

prem

[fmatrine]

Dear Premkumar,

Thanks for the assistance given.

regards