Session Initiation Protocol, or SIP, is a protocol to achieve a voice over IP (VoIP) call. SIP creates real-time sessions of audio or video between two endpoints. With SIP, you can create and terminate sessions with multiple parties in an IP network. Sessions can be initiated between only two parties or multiple parties on a conference call.


SIP trunking replaces the traditional style connection to your telephone service provider. Instead of using a dedicated circuit for phone calls, SIP Trunks connect your PBX to the public internet. A SIP trunk is virtually installed over your existing internet connection and replaces the need for analog phone lines.

TelWare’s SIP trunking solutions will help you to cut down on your high monthly phone bills and eliminate many of your costly IT and maintenance fees. In addition to cutting monthly costs, SIP trunking provides scalability and reliability.

SIP phones look like regular phones, except that they have extra buttons for the variety of functions that VoIP offers, such as call forwarding, conferencing, and speed dialing. SIP supports video as well as voice calls, so some phones have screens and cameras for video calling. Video calls are possible on the local network, or to remote VoIP phones through SIP trunking.

If your company services cities beyond the local telephone area code of your headquarters, you may want your customers there to feel like they are working with a local company. Establishing local presence is one way to do this without opening satellite offices in each city. With TelWare SIP, you can have a local number for any city in the United States. You can then get this number published in the local phonebook to establish local presence for your business.


There are some definite advantages to using SIP, including:

  • Requiring less support and maintenance
  • Reducing costs by eliminating the need for separate circuits for voice and data
  • Supporting multiple forms of communication, including video conferencing and instant messaging
  • Providing greater flexibility with regards to how you use your telephone service
  • Allowing for greater control over employee calls
  • Improving the quality of calls by creating dedicated “channels” for each use