VoIP is a technology devised to utilize your existing IP infrastructure to carry voice. This can be accomplished by using intelligent phones that have both a MAC address (NIC card) and an IP address. Your voice is encapsulated into an IP packet and transmitted to the PBX. This allows your phone to be identified by an IP address instead of a phone number. The reason behind this is so that like a computer, a phone can be relocated easily to any location without the need for patching or PBX reprogramming. Essentially, since the PBX now communicates to the phone using IP, it will know what phone number to send and receive voice information regardless of location.
This was first published in April 2002