How does an IP telephone system work? A guide to the basic workings of an IP telephone system Introduction An IP (Internet Protocol) telephone system is one which uses VoIP (Voice over Internet Protocol) to make a call over the internet rather than the traditional analogue phone network. An IP telephone system allows calls to be made more cheaply than on a traditional analogue phone network. Codecs All IP telephone systems use codecs to convert the analogue signal from the microphone into a digital data signal suitable to be sent over the internet. At the speakers end the codec compresses the data so less bandwidth is needed to transmit it. Then at the listeners end the codec decompresses the data so it can be converted into sound. Phone Lines In a call over a traditional phone network you basically take over the entire copper line for the duration of your call. By using your internet connection and a technology called packet switching IP telephone systems use much less of the copper line’s capacity. Calling Analogue Phones As traditional analogue phones don’t have the required codecs, how can IP phone systems make calls to them? In this case the phone service provider handles the compression and decompression turning the signal back to analogue before it reaches the other end. Along the Way ∗ The call starts with the device being used to make the call – could be a VoIP handset or PC. ∗ It then goes to the company’s IP telephone system hub/switch. ∗ From there it it’s sent over the internet to the service provider’s VoIP server. ∗ The VoIP server then connects the call to its destination. ∗ If the recipient is using VoIP the process then happens again in reverse.
Pages to are hidden for
"How does an IP telephone System work"Please download to view full document