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Community Member

Questions about the bandwidth.

Let me explain my existing environment

as follows :

- I have two 2801 routers with


- Each router has Four-port FXS

connected to the phones

- The bandwidth between these routers

is 256 Kbps ( Leased Line )

My qouestions are as follows :

1. How many bandwidth are a call

comsumed ( per call ) ?

2. To ensure that the bandwidth of

VoIP is not excess the maximum

bandwidth of leased line. And to

ensure that the priority of VoIP

is always higher than the priority

Data. I will use RSVP and CBWFQ

with ip precedence. Are these

features suitable for the

situation ?

Thanks!! : )

Community Member

Re: Questions about the bandwidth.

I'm sorry I place this question on the wrong forum.


Re: Questions about the bandwidth.


regarding bandwidth consumption it depends upon the kinda codec which you are gonna use up there.

ofcourse g.729 does uses minimal amount of bandwidth and also that get reflects in ur quality.

If you are gonna used some kinda RTP compression out there that can always reduce the packet length drastically to lesser size which will be easier as well u will be able to use the B/W effectively .

regarding the priority part you can always use up LLQ to have high priority for your VOICE traffic and deploy CBWFQ for your data traffic.

if u wanna have sample configs would suggest to do a search in cisco about the same ,if u need further assistance do revert..


Community Member

Re: Questions about the bandwidth.

g.711 requires 80kbps

g.729 requires 24kbps

LLQ is the way to go and is the recommended way to impliment QoS for VOIP these days.

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