Telephony
SIP trunkingSIP
SIP trunking uses the Session Initiation Protocol (SIP) to connect a phone system to the public telephone network over the internet, replacing physical phone lines. It's how a voice platform originates and receives calls programmatically and at scale.
SIP handles call setup, routing and teardown; the media (audio) rides alongside it. For AI voice agents, SIP trunks provide the concurrency and number provisioning needed to run many simultaneous calls.
Related terms
VoIPVoice over Internet Protocol — carrying phone calls over the internet instead of traditional phone lines. The transport layer under most modern voice agents.ConcurrencyThe number of phone calls a voice platform can handle at the same time. Concurrency sets how much inbound spike or outbound volume you can run.Call routingDirecting an incoming call to the right destination — person, team, or queue — based on rules, caller input, or what the AI agent understands.
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