Fault tolerant virtual tandem switch

US7227837B1 · kind B1 · utility

Assignee

• AT&T Labs, Inc. · US

Inventors

• Haifeng Bi · Austin, US
• George C. Allen, Jr. · Pflugerville, US
• Randy Beamon · Cedar Park, US
• Weijing Chen · Austin, US
• Janice Elaine Doerner · Dripping Springs, US
• Mehran Esfandiari · Oakland, US
• Gary Jonathan Gibbons · San Antonio, US
• Paul August Kaschube · Austin, US
• Bruce A. Nance · Chesterfield, US
• John Pinch · Richardson, US
• Tina Sigarto · Raleigh, US
• Barbara Smith · San Antonio, US
• Matthew Wayne Stafford · Austin, US
• GEORGE YOUNG · Atlanta, US

Key dates

• Filing date: Mar 23, 2000
• Grant date: Jun 5, 2007
• Expiry date: Mar 23, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04L2012/5687
• WIPO field: Digital communication
• WIPO sector: Electrical engineering

Abstract

A system and method for reducing and surviving failures in a voice trunking over ATM (VTOA) environment includes an ATM network having a plurality of interconnected ATM switches. The VTOA system also includes a CS-IWF complex having a plurality of interconnected CS-IWF units, each unit having a plurality of processors. An end office building may also be provided for interaction with the VTOA system. The end office building includes multiple T-IWFs, and a switch that distributes calls among the T-IWFs in a load sharing manner. Each T-IWF has a plurality of processors and is part of the VTOA system. A switch management system is also provided in the VTOA system. In order to reduce and survive failures, the switch management system includes a plurality of switch management system units. At least one of the switch management system units is a backup unit for at least one primary switch management system unit. Each switch management system unit provides application redundancy within itself.