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Internet Requirements

Internet Requirements

If you use a desk phone (also known as SIP phone or Internet phone) or a Softphone on your PC, you will be making and receiving calls through your internet connection.

The quality of your internet connection can affect the quality of your phone conversations

Voice traffic competes for space with other activities such as web browsing and music download.

Voice has preference over other data

In most cases, a domestic broadband connection is adequate for small business users. Of course, some of our users may wish to make a higher volume of calls. For users wishing to make 4 or more calls concurrently, we advise that they do a simple internet speed test. In every case, if bandwidth is an issue, there are measures you can take to improve the situation.

In this section:

Test your internet bandwidth  |  What to do to improve the situation  |

A simple calculation to see if you have enough bandwidth

Even though you may think you are subscribing to a certain internet capacity, the actual speed or capacity of your internet connection is usually not the same as the advertised number. For example a Virgin Media 10Mb line means you can achieve download speeds up to 10Mb; they do not guarantee you will always have 10Mb. Upload speeds are always significantly less than download speeds unless you pay for a more expensive internet connection.

 To check your actual internet upload/download capacity and line quality:

Type www.speedtest.net into any internet browser

Run the Speed test - it will give you an upload and download result. In this example it was 9.8Mbps download and 0.48Mbps (or 480kbps) upload from a 25Mb Virgin line

Run the Ping test which tests the overall quality of the line; an 'A' or 'B' is fine.

A "C" or lower means you might need to take some action if you want to use VoIP, which will be discussed later.

VoIP typically needs 150kbps bandwidth per call (that's kilobits per second)

Additional calls on the same line require 120kbps per call, but for ease of calculation we'll use the higher value below.

Internet connection bandwidth is usually advertised in Megabits (per second) Mb and 1024kb = 1Mb (let's use 1000kb for ease of calculation)

So using my results and taking the lower of the two - the upload capacity - into account, I can run 480 / 150 = 3 concurrent VoIP calls with good clear quality. If you are not making concurrent calls, you can run more VoIP phones;

VoIP takes preference over other data traffic, however it's a good idea to estimate not only the number and frequency of concurrent calls you are likely to make but any other activity on your internet line such as website surfing, upload and download of data, live streaming of video and music, all of which might affect the capacity.

What to do if you require more bandwidth, or to improve jitter

The ping test measures jitter in the line. You can try to correct a poor score by re-booting the router, and running another ping test.

If this doesn't improve the score we suggest in the first instance you call your ISP (Internet Service Provider) and ask them to investigate the performance.

If you want to run more VoIP phones than your bandwidth can accommodate:

One option might be to upgrade your internet connection. However before you do this, we can show you how to configure your phone to compress the voice data packets by a third so that instead of requiring 150kbps, a call only requires 50kbps.

What this means is that the call quality "dips" to that of a mobile phone. Speech is fine, but music may be a bit "jittery".

For more information or help please do not hesitate to Contact Us