RFC 3666 · BEST CURRENT PRACTICE · 2004

Session Initiation Protocol Public Switched Telephone Network Call Flows

Overview

RFC 3666, “Session Initiation Protocol Public Switched Telephone Network Call Flows”, is a Best Current Practice document published in January 2004 by A. Johnston, S. Donovan, R. Sparks, C. Cunningham, K. Summers. The canonical text is published by the RFC Editor.

Abstract

This document contains best current practice examples of Session Initiation Protocol (SIP) call flows showing interworking with the Public Switched Telephone Network (PSTN). Elements in these call flows include SIP User Agents, SIP Proxy Servers, and PSTN Gateways. Scenarios include SIP to PSTN, PSTN to SIP, and PSTN to PSTN via SIP. PSTN telephony protocols are illustrated using ISDN (Integrated Services Digital Network), ISUP (ISDN User Part), and FGB (Feature Group B) circuit associated signaling. PSTN calls are illustrated using global telephone numbers from the PSTN and private extensions served on by a PBX (Private Branch Exchange). Call flow diagrams and message details are shown.

Abstract as published in the RFC, via rfc-editor.org.

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

The canonical text of RFC 3666 is hosted at rfc-editor.org. Available in TXT,HTML.

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