A trunk is a communications line or link designed to carry multiple signals simultaneously to provide network access between two points. Trunks typically connect switching centers in a communications system. Trunks are A trunk is a relationship between two network elements that use the SIP protocol to communicate between themselves.
Trunks can be setup set up via two methods:
A Source IP address, Protocol (UDP, TCP, TLS), and Source Port associated to with an Orchestrator’s SIP Signaling IP address and port. The Orchestrator’s “listening” port will always be 5060 for UDP and TCP connections, and 5061 or 5062 for TLS v1.2 connections. TCP and TLS connection connections use random ephemeral source ports. So for For these connection connections, use a port value of 1, which signifies the Orchestrator will accept SIP messages from the Source IP address regardless of the Source Port used.
A SIP Registration can be configured to the Orchestrator's IP(s).
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An alternate and completely different definition of a Trunk is a single port, call path, session, or voice channel between to two network elements.