What is a SIP trunk used for?

Connecting an existing PBX, call-center platform, or dialer to the phone network without physical phone lines.

Does Offshorevoip offer SIP trunks without KYC?

Yes. Trunks activate without document uploads, from 4 concurrent channels on Launch to 50 on Enterprise.

What is the difference between a SIP trunk and Cloud PBX?

A trunk connects your own phone system to the network. Cloud PBX is the phone system itself, hosted for you.

Is a SIP trunk encrypted?

It can be. Offshorevoip supports SRTP media on every plan and TLS signaling from Business.

what is a sip trunk

What is a SIP trunk?

By Offshorevoip Network Desk·Voice infrastructure editorial·Last updated: 2026-09-29

TL;DR

A SIP trunk is a virtual phone line delivered over the internet using the SIP protocol, connecting your PBX or softphones to the public telephone network.

Definition

what is a sip trunk: A SIP trunk is a virtual phone line delivered over the internet using the Session Initiation Protocol, connecting a PBX, dialer, or softphones to the public phone network; capacity is measured in concurrent channels.

Channel = 1 live call

Size by peak simultaneous calls

4–50

Channels at Offshorevoip

Launch 4 through Enterprise 50

SIP

Standard protocol

Works with most PBXs and dialers

A SIP trunk replaces or complements traditional PRI/analog circuits with IP-based calling capacity. You register endpoints or a PBX to a provider and send/receive calls as SIP sessions.

Offshorevoip sells SIP trunks with No KYC activation — so the technology definition stays standard while onboarding policy stays privacy-first.

“The number that matters on a SIP trunk is concurrent channels. Seats tell you who can call; channels tell you how many can call at once.”

Offshorevoip Network Desk·Voice infrastructure editorial

SIP trunk behind an existing PBX

An operator already runs FreeSWITCH. They add an Offshorevoip SIP trunk, point peers to provided credentials, and validate codecs/encryption — without a KYC document stage.

PBX peering
Softphone registration
Codec/encryption by plan
No KYC

How to connect a SIP trunk

1Get the trunk host, credentials, and transport (UDP, TCP, or TLS).
2Add the trunk in your PBX or dialer with those settings.
3Map inbound DIDs and outbound routes.
4Place test calls both ways and check audio in each direction.

SIP trunk building blocks

Component	Role
SIP registration	Auth endpoints
Codecs	Audio quality
Encryption	SRTP/TLS
DIDs	Caller reachability
Concurrent channels	Capacity

Source: Offshorevoip product policy · Updated 2026-09-29

FAQ: what is a sip trunk

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Standard SIP. Privacy-first activation.

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