RFC 3372: Session Initiation Protocol for Telephones
Abstract
The popularity of gateways that interwork between the PSTN (Public Switched Telephone Network) and SIP networks has motivated the publication of a set of common practices that can assure consistent behavior across implementations. This document taxonomizes the uses of PSTN-SIP gateways, provides uses cases, and identifies mechanisms necessary for interworking. The mechanisms detail how SIP provides for both ‘encapsulation’ (bridging the PSTN signaling across a SIP network) and ‘translation’ (gatewaying).
RFC 3372 – Sesseion Initiation Protocol for Telephones
This is a “Best Practices” document that describes a methodology for encapsulating ISUP (ISDN User Part) messages within the SIP protocol. This facilitates the transmittion of call setup components between SIP gateways without loss of signalling components not normally used in a SIP only environment.
components
RFC 3261: Session Initiation Protocol
RFC 3302: MIME media types for ISUP and QSIG objects
RFC 2633: S/MIME Version 3 Message Specification – new MIME type – application/isup
RFC 2976: SIP INFO method
RFC 2327: SDP: Session Description Protocol
RFC 3219: TRIP: Telephone Routing over Internet Protocol
April 7, 2023
Phone System 