Method for rerouting a packet-mode data connection

• US 5,809,011 A
• Filed: 08/27/1996
• Issued: 09/15/1998
• Est. Priority Date: 02/28/1994
• Status: Expired due to Term

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Telecommunications Oy (Nokia Corporation)
• Inventors: Almay, Heikki
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): HYUN, SOON D
• Application Number:
  US08/702,489
• Time in Patent Office: 749 Days
• Field of Search: 370/216, 370/217, 370/218, 370/221, 370/223, 370/224, 370/225, 370/227, 370/228, 370/229, 370/235, 370/395, 370/399, 370/241, 370/242, 370/248, 340/825.01, 340/827, 379/221
• US Class Current: 370/395.32
• CPC Class Codes: H04L 2012/5619 Network Node Interface, e.g. tandem connections, transit switching
• CPC Class Codes: H04L 2012/562 Routing
• CPC Class Codes: H04L 2012/5627 Fault tolerance and recovery
• CPC Class Codes: H04L 2012/563 Signalling, e.g. protocols, reference model
• CPC Class Codes: H04L 49/153 ATM switching fabrics having parallel switch planes
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

The invention relates to A method for rerouting a connection-oriented packet-mode data connection, especially an ATM network data connection. In the method, traffic to be transferred between two nodes of the network is rerouted from a first, inactivated route to another, new route. To minimize loss of data during rerouting, the node initiating the rerouting sends a notification of the rerouting to the node of the opposite end and simultaneously starts to receive traffic from both routes, the opposite end node, having received the notification concerning the rerouting, starts to receive traffic from both routes, both nodes switch transmission to a new route so that the opposite end receives data from only one route at a time, and that rerouting is terminated for both nodes in that they independently cease to listen to a route to be deactivated.

Claims

1. A method for rerouting a packet-mode data connection, wherein traffic to be transferred between two nodes of the network is rerouted from a first, deactivated route to another, new route, comprising the steps of:

the node of one end of the connection initiating rerouting from said deactivated route by sending a notification of the rerouting to the node of the opposite end of the connection and simultaneously starting to receive traffic from both of said routes;

the opposite end node, having received said notification of the rerouting, starting to receive traffic from both of said routes,

both of said nodes switching transmission of data to said new route, so that each end receives data from only one route at a time, and

terminating rerouting for both of said nodes such that both of said nodes independently cease to listen to said deactivated route.

2. The method as claimed in claim 1, wherein:

the in said switching, said opposite end node switching transmission to said new route before said initiating node, said switching by said opposite end node being effected in response to receiving of said notification concerning said rerouting; and

transmission of data to said new route being initiated only after a buffering period having a predefined duration.

3. The method as claimed in claim 1 or 2, further comprising:

said node initiating said rerouting performing time supervision after said sealing of said notification of said rerouting; and

after the expiration of a time-out period said node initiating said rerouting ceasing transmission to said deactivated route.

4. The method as claimed in claim 1 or 2, further comprising:

said node initiating said rerouting, after transmission of the notification of rerouting, waiting for an acknowledgment of reception of said notification from said opposite end node, whereafter

said node initiating said rerouting ceasing transmission to said deactivated.

5. The method as claimed in claim 3, wherein:

said node initiating said rerouting initiates transmission to said new route only after elapsing of a buffering period of a predefined duration beginning from when said node initiating said rerouting has stopped transmission to said deactivated route.

6. The method as claimed in claim 1, wherein:

said packet mode data is transmitted in ATM cells.