Bandwidth calculation voice router for 200 ip phone 7821/8811

[adeebtaqui]

Hi,

I want to make a VOIP solution including BE6000M as call manager and ISR as VOICE gateway.

But I am not sure how to estimate or size voice router to support 200-300 cisco 7821/8811/8832 ip phones?

Pls advice how to size the gateway requirement

[Jaime Valencia]

I'd suggest you reach out to a Cisco partner with voice specializations for assistance with this.

[Robert Shaw]

There are a number of tools available here,

https://www.cisco.com/c/en/us/support/web/tools-catalog.html

One of them is a DSP Calculator that you will need to calculate the number of DMVPN Modules needed to handle the various Media Devices.

There is also a bandwidth calculator that could come in handy.

As Java suggests though it would be best to get it sanity checked by a Cisco Partner before making any purchases.

[adeebtaqui]

I am working for Cisco partner but we do not have VOIP expert with us. Can you please advice about any doc or share your experience that would help me

for SIP 300 extension DID/DOD service, does it mean I have to add cube license of 300 for voice gateway like 4431 which supports 350 phones

[TONY SMITH · Accepted solution]

I assume that the proposed ISR which you mention will be terminating a SIP service which you'll be using for your incoming and outgoing external calls.  If that's the case then its licensing and capacity needs to match the number of concurrent external calls that you expect.  This will be significantly less than the number of actual phones on your BE6K, unless your business is such that everyone is on the phone all the time.

Just making some wild guesses you may be looking at something like 20-50 concurrent calls, and you probably won't need anything as powerful as a 4431 either.  Whatever router you pick you'll need UC licence, maybe Security depending on how it's going to be deployed, and CUBE Trunk licences to suit the number of SIP channels.