Ideally for VoIP to operate, you will need an internet connection with a speed of at least 128 kbps (like ADSL) to make sure that you get good call quality and successfully use of VoIP. The reasons for this are :
- You need at least 64 kbps download plus 64 kbps upload bandwidth to make an uncompressed VoIP call. Otherwise you will need to compress your VoIP traffic using compression codecs such as G.729 which can decrease the bandwidh to approximately 30 kbps. These ethods of compression are normally used in situations when multiple calls are going over the same connection, NOT when bandwidth is restricted to less than 128 kbps. If you have dial-up you will be very fortunate and incredible lucky to achieve decent call quality even if you are using VoIP compression. You can test your internet speed here using Speedtest.net
- A broadband connection is ‘always on’, thereby ensuring that you can receive and make calls with minimum interruption to your VoIP Service.
- You want to make sure that you have enough bandwidth left over for typical Internet traffic (e.g. emails, cloud services, web browsing, file downloads, video streaming etc). However some routers will allow you to prioritise your VoIP traffic to ensure that you always have sufficient bandwidth available for using VoIP.