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Voice Codec Bandwidth Calculator

While reading the tedious bandwidth consumption chapter and how to calculate it, I found that between the endless numbers there is a small light. I do not know if the exam expect me to calculate bandwidth (and I do hope it does not) but for real life there are few options that make your life easier.

The first option is Cisco’s Voice Codec Bandwidth Calculator which is only available if you have a valid CCO login. This is how it would look (using totally random options):

Voice Codec Bandwidth Calculator - Step I

Step I:

This is where you choose the Codec and the Voice protocol to be used.

In addition you have to type in the number of calls you expect on the line  – this is for simultaneous calls.

Voice Codec Bandwidth Calculator - Step II

Step II:

Here you have to type your Voice Payload in bytes.

The other parameters are the Media access, this is the type of connection you use and the Tunnel or Security load (in bytes) that would be used.

When you submit your information you will get a detailed output with your selections and results. This report is full of numbers which I guess will clear during my studies but even now, when I’m short of some definitions I can appreciate the information and it is obviously very helpful in planning a voice network

This is an example of a result page:

Voice Codec Bandwidth Calculator - Results

and the second part of the results:

Voice Codec Bandwidth Calculator - Results

This is a very details tool but as I mentioned, it requires a valid CCO and not everyone can pay for it (though I assume that if you have this type of voice network you can and should get maintenance for your equipment)

The second option is a free four Voice over IP calculators. While it is not as descriptive and comprehensive as the Cisco version, it does give you the general idea with good numbers. Check this example:

free Lines and VoIP Bandwidth Calculator

Unlike the fancy Cisco tool,  this free tool have fewer options of coding algorithms.

After you select the packet duration (samples over time) you can either type in the number of simultaneous calls and receive the required bandwidth OR type the available bandwidth and receive the number of possible calls.

The free version has three more options:
Erlangs and Bandwidth Calculator
Minutes and Lines Calculator
Erlangs and Lines Calculator

One more tool from Cisco (available for CCO only) is DSP Calculator which take the router model and IOS version, on board HWIC slots and few more parameters and give the DSP Module Requirements. I think it is beyond the scope of the exam but it is a handy tool.

  1. Taneka
    November 24, 2012 at 3:06 pm

    Thanks a lot for sharing this with all folks you actually know what you are talking approximately! Bookmarked. Kindly additionally consult with my web site =). We can have a link change agreement among us!

  2. Carlos
    March 18, 2010 at 10:31 am

    It’s a very handy tool I’ve heard about it in a CBT nuggets video on ONT.

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