SIGTRAN

What is Signal Transport (SIGTRAN)?

SIGTRAN (Signaling Transport Working Group) is a family of protocols for transporting telecom signaling messages over IP. The telco switch sends SS7 signals to a signaling gateway (SG), transforming them into SIGTRAN packets. These packets then move via IP to the following SG, a softswitch if the destination is not another PSTN, or to the next signaling gateway. SIGTRAN uses the Stream Control Transmission Protocol (SCTP) for reliable transport.

How does SIGTRAN work?

SIGTRAN is frequently used in Signaling Gateways, which enable voice-over IP networks to communicate with conventional telephone networks using circuit switching and SS7. The gateway receives the SS7 network's signaling messages and uses SIGTRAN to forward them to the IP side.

Different types of SIGTRAN

1. There are several protocols in the SIGTRAN family:
2. Stream Control Transmission Protocol (SCTP), RFC 2960, RFC 3873, RFC 4166, RFC 4960.
3. ISDN User Adaptation (IUA), RFC 4233, RFC 5133.
4. Message Transfer Part 2 (MTP) User Peer-to-Peer Adaptation Layer (M2PA), RFC 4165.
5. Message Transfer Part 2 User Adaptation Layer (M2UA), RFC 3331.
6. Message Transfer Part 3 User Adaptation Layer (M3UA), RFC 4666.
7. Signalling Connection Control Part (SCCP) User Adaptation (SUA), RFC 3868.
8. V5 User Adaptation (V5UA), RFC 3807.