How Does A SIP Trunk Work?

What is SIP trunk and how does it work?

A SIP trunk is the virtual version of an analog phone line.

Using SIP trunks, a SIP provider can connect one, two, or twenty channels to your PBX, allowing you to make local, long distance, and international calls over the Internet.

What does SIP trunk mean?

Session Initiation Protocol (SIP) trunking is a service offered by a communications service provider that uses the protocol to provision voice over IP (VoIP) connectivity between an on-premises phone system and the public switched telephone network (PSTN). SIP is used for call establishment, management and teardown.

How many SIP trunks do I need?

When the question “How many trunks do I need?” comes to mind, for most vendors, they’ll rather stick to the old rule of thumb — one trunk for three employees. For others, they take it as duplicating the current number of trunks you’re using (in cases where it applies).

How do you make a SIP trunk?

Here is a step-by-step guide to the general process of setting up a SIP trunk.

  • Log into your PBX system.
  • Select the ‘trunks’ option.
  • Create and add a SIP trunk (this will connect the system externally)
  • Name the trunk.
  • Set the outbound caller ID (your business’ phone number, or whichever number you want to use)