This paper 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).
Did you find this white paper useful?
26 out of 50 users found this white paper useful
Related white papers
GPRS White Paper
The General Packet Radio System (GPRS) is a new service that provides actual packet radio access for mobile Global System for Mobile Communications (GSM) and time-division multiple access (TDMA) users....
SIP: Protocol Overview
The Session Initiation Protocol (SIP) is a signaling protocol for initiating, managing and terminating voice and video sessions across packet networks. SIP sessions involve one or more participants and can...
Layer 3 Malformed Packet Testing in MCI's Public IP Network
Malformed packets associated with routing protocols can cause undesirable consequences if not detected and contained properly as close to the originator as possible. This issue magnifies in scope and complexity...
Delivering Unique Services that Meet Customer Needs
The telecommunications industry is rapidly re-inventing itself to meet its changing and expanding role in the business world. With the advent of cellular, WiFi, WiMax and increasingly powerful and...
Understanding the OSI 7 Layer Model
This document provides a full length explanation of the OSI 7 layer model including the role of each layer and of the stack. This model defines how applications running upon...
IEEE 802.11 Tutorial
Approval of the IEEE 802.11 standard for wireless local area networking (WLAN) and rapid progress made toward higher data rates have put the promise of truly mobile computing within reach....
Understanding TCP/IP
The name TCP/IP refers to a suite of data communication protocols. The name is misleading because TCP and IP are only two of dozens of protocols that compose the suite....
