Method for resilient call setup through ATM networks for Softswitch applications

• US 20030112761A1
• Filed: 12/14/2001
• Published: 06/19/2003
• Est. Priority Date: 12/14/2001
• Status: Active Grant

• Current Assignee: Nokia Siemens Networks GmbH & Company KG (Nokia Corporation)
• Original Assignee: Siemens Communications Incorporated (Siemens AG)
• Inventors: Sen, Ercan
• Granted Patent: US 7,065,041 B2
• Time in Patent Office: Days
• US Class Current: 370/242
• CPC Class Codes: H04L 12/5601 Transfer mode dependent, e.g. ATM
• CPC Class Codes: H04L 2012/5618 Bridges, gateways [GW] or interworking units [IWU]
• CPC Class Codes: H04L 2012/5627 Fault tolerance and recovery
• CPC Class Codes: H04L 2012/5685 Addressing issues
• CPC Class Codes: H04L 45/10 Routing in connection-oriented networks, e.g. X.25 or ATM
• CPC Class Codes: H04L 45/24 Multipath

Abstract

A method establishes two redundant Switched Virtual Channel (SVC) connections through ATM Networks using the same ATM End System Address (AESA) from a source ATM End Point to a destination ATM End Point. The method provides end-to-end path protection without relying on any underlying resiliency features of an ATM Network so that the set-up model is transparent to the underlying ATM Network.

Claims

1. A method for establishing resilient paths through an asynchronous transfer mode (ATM) network including at least an ingress media gateway, an egress media gateway, a first ATM switch, a second ATM switch, a link A connecting said egress media gateway to said first ATM switch, a link B connecting said first ATM switch to said ingress media gateway, a link C connecting said egress media gateway to said second ATM switch, a link D connecting said second ATM switch to said ingress media gateway, said method comprising:

a. setting up a primary SVC connection from said egress media gateway to said ingress media gateway by using a specified ATM end system address (AESA) of a port on said igress media gateway over said link A; and

,

b. setting up a backup SVC connection using the same AESA from said egress media gateway to said ingress media gateway over said link C,

wherein at least one primary SVC and one backup SVC connections are established between said egress media gateway and said ingress media gateway over different routes for the same call between said egress end office and said Ingress end office.

2. The method of claim 1 further comprising:

c. detecting a failure in said primary SVC; and

,

d. switching the call connection between said egress end office and said ingress end office from the primary SVC to said backup SVC,

whereby if there is a failure in said primary path, the call connection between said egress and ingress end offices are switched to said backup SVC by an Automatic Protection Switching (APS) signal in a manner that is not dependent on the physical configuration of said ATM network and by using end-to-end supervision of the call connection path.

3. The method of claim 2 further comprising:

e. informing all affected SVCs of the failure status of said primary SVC through the corresponding backup SVC using said APS signal.

4. The method of claim 3 wherein said detecting step c. further comprises:

f. detecting an ATM switch failure.

5. The method of claim 3 wherein said detecting step c. further comprises:

g. detecting a media gateway failure.