How do you determine the amount of bandwidth required for VoIP?


Is there an easy way to determine the amount of bandwidth required for a given number of voice paths through an IP network? I want to be certain that there is sufficient bandwidth to avoid quality issues with voice transmissions before going down the VoIP road.

Answer this Question


2 total
Vote Up (26)

Here's an article that covers bandwidth consumption. You might find it helpful, TheCount. See the links on that page as well, for more information.

"VOIP Bandwidth consumption naturally depends on the codec used.

When calculating bandwidth, one can't assume that every channel is used all the time. Normal conversation includes a lot of silence, which often means no packets are sent at all. So even if one voice call sets up two 64 Kbit RTP streams over UDP over IP over Ethernet (which adds overhead), the full bandwidth is not used at all times.

A codec that sends a 64kb stream results in a much larger IP network stream. The main cause of the extra bandwidth usage is IP and UDP headers. VoIP sends small packets and so, many times, the headers are actually much larger than the data part of the packet."

Vote Up (21)

There is a simple calculator that will help you determine this:

You need to know something about the type of CODEC used for voice compression in your particular case (as noted in JimLynch's answer), as well as the packet frequency, so that the calculation will have validity.  Hopefully this will help you ensure you have sufficient bandwidth for good voice quality.  Be certain that you have enough bandwidth, because if you don't you will get packet loss, and as soon as that happens, your going to get IMs/emails/calls from everyone from the CEO to the janitor.  Don't ask me how I know!  Good luck!

Ask a question

Join Now or Sign In to ask a question.
Yahoo has acquired online video streaming company RayV with the aim of distributing content to more people, particularly via mobile devices.
Apple users accessing Gmail on mobile devices could be at risk of having their data intercepted, a mobile security company said Thursday.
In wake of psychological experiment, group challenges users to take a Facebook break and find out if it makes them happier.
LinkedIn is trying again to build a service on mobile that helps keep people in touch, even when they're not actively job hunting.
More than 40 privacy, civil rights and religious groups have called on President Barack Obama's administration to provide a "full public accounting" of long-time email surveillance of prominent Muslims living in the U.S., following a news report detailing the spying by the U.S. National Security Agency and FBI.
Microsoft will revamp its Office 365 lineup for small and midsize businesses (SMBs), adding features, dropping prices and increasing the flexibility to mix and match them with Office 365 plans for enterprises and with stand-alone applications.
U.S. National Security Agency whistleblower Edward Snowden has applied for extended asylum in Russia, according to news reports.

Facebook said police in Greece made two arrests last week in connection with a little-known spamming botnet called "Lecpetex," which used hacked computers to mine the Litecoin virtual currency.

As many as 50,000  

Mocana's Atlas platform is intended to make it easier for users to access enterprise apps from their smartphones without compromising security.
Microsoft will bundle Yammer with more editions of Office 365, adding the enterprise social-networking product to the suite's editions for schools and midsize businesses.
Join us: