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VoIP Bandwidth Calculator and Erlang


Different protocols consume different amount of bandwidth. In most of the cases the bandwidth consumed by VoIP codec is not that much, the extra burden is caused by different protocol headers. VoIP bandwidth calculation and planning is one of the most important part in designing a VoIP Network.

To make this task easy, i cam across a very interesting website. The website is:

http://www.bandcalc.com

This is an interesting site, which you can use to calculate the bandwidth required for a VoIP network using different parameters like, payload size, frames per second etc. Please explore and enjoy this interesting website.

What is an Erlang?

Erlang is a traffic measurement unit commonly used in telecom. It is used to describe a traffic volume of one hour.

Example: 20 calls in an hour with 5 minutes of conversation average.

You calculate the number of Erlangs as below:

Traffic minutes in the hour: 20 x 5 = 100 minutes
Hour of traffic inside one hour: 100/60 = 1.66 Erlangs

You can get these measures from a call logger and use it to design your network to calculate the number of lines required. Once the number of lines is known, it is possible to calculate the bandwidth requirements.