The term "SIP Trunking" is probably quite a familiar term to anyone who works within or is an enthusiast of the field of Voice of IP (VoIP) solutions. Until now, this term has thankfully been rarely used, but its importance is increasing dramatically. Basically SIP Trunking is a technique where by an IP based phone system can manage numerous telephone numbers from one individual account.
The classical SIP method is characterised in that each end user device for each number requires its own account. In contrast, SIP Trunking makes it possible, to manage multiple extension numbers via one account. This methodology is particularly popular with large enterprise where multiple devices require their own number, although it is growing in popularity amongst the SMB market segment as VoIP technology becomes more commonplace.