VoIP Trunks Introduction

VoIP Trunks are phone lines that transmits calls over the Internet. A VoIP provider can assign a local number to one or more cities or countries and route it to the PBX phone system. Usually VoIP trunks are cheaper than traditional PSTN trunks.

SIP protocol and & IAX2 protocol

Yeastar S-Series VoIP PBX supports VoIP trunk based on SIP (Session Initiation Protocol) protocol and IAX (Inter-Asterisk eXchange ) protocol.
  • SIP protocol

    SIP ( Session Initiation Protocol ) is a multimedia communication protocol developed by the IETF ( Internet Engineering Task Force ), an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants.

  • IAX2 protocol

    IAX2 is a VoIP protocol native to Asterisk. IAX2 is attractive in bandwidth conservation and NAT traversal. IAX2 is not the an IETF protocol, it is not supported widely and is used rarely.

VoIP Trunk Types

Yeastar S-Series VoIP PBX supports the following VoIP trunk types:

  • VoIP Register Trunk: Registration based VoIP trunk. VoIP Register Trunk uses the username and password for registration with SIP providers.
  • VoIP Peer Trunk: IP based VoIP trunk. Uses the IP address and port of PBX for authentication.

  • VoIP Account Trunk

    Account Trunk is designed for connection between Yeastar S-Series VoIP PBX and other devices. Yeastar S-Series VoIP PBX will act as a VoIP account provider, the other device should register this account to connect to Yeastar S-Series VoIP PBX.