SIP Trunk

A SIP trunk is a virtual phone line that uses the SIP protocol over an IP network to connect an enterprise's phone system to the public telephone network or to other VoIP services. SIP trunks replace traditional physical phone lines with software-defined connections that can be provisioned, scaled, and managed digitally. In contact centre AI deployments, SIP trunks are the inbound and outbound call channels through which AI Agents receive and make calls. They are provided by telecommunications carriers or directly by cloud contact centre platforms, and must be configured to support the codec, capacity, and failover requirements of the AI deployment.

For enterprise teams, a SIP Trunk matters because real-world outcomes depend on how the capability is integrated, governed, and measured — not just on the underlying technology. SIP trunks replace traditional physical phone lines with software-defined connections that can be provisioned, scaled, and managed digitally.

Key Points

• Virtual phone lines using SIP over IP — replacing physical ISDN or PRI circuits
• Software-defined: instantly provisioned, scaled, and managed without hardware
• The inbound and outbound call channels for AI Agent voice interactions
• Must be sized for peak concurrent call volumes expected in the AI deployment
• Configured to support required codecs, redundancy, and failover for enterprise reliability