Method and system for restoring a subscriber context

• US 7,215,955 B2
• Filed: 04/27/2001
• Issued: 05/08/2007
• Est. Priority Date: 11/06/1998
• Status: Expired due to Term

• Current Assignee: Nokia Solutions and Networks US LLC (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Forssell, Mika
• Primary Examiner(s): Gelin; Jean
• Assistant Examiner(s): Iqbal; Khawar
• Application Number:
  US09/844,879
• Publication Number:
  US 20020004395A1
• Time in Patent Office: 2,202 Days
• Field of Search: 455/433, 455/45, 455/186.1, 455/445, 455/560, 455/426, 455/418, 455/423, 455/424, 455/8, 370/394, 370/328, 370/331, 370/336
• US Class Current: 455/433
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 8/30 Network data restoration; Network data reliability; Network data fault tolerance

Abstract

A method and system for restoring a subscriber context in a network element of a mobile communication network is described, wherein a new subscriber context which has been updated after the latest restart is indicated by transmitting a corresponding restart information to the network element. Based on the restart information the network element continues the use of new subscriber contexts updated after the latest restart and inactivates old subscriber contexts updated before the latest restart. Thereby, the amount of unnecessary subscriber context re-activations and the corresponding downtime of the service is reduced. Moreover, the amount of signaling required after the restart is reduced, since a smaller number of subscriber contexts have to be re-established.

Claims

1. A method for restoring a subscriber context in a mobile communication network, the method comprising:

storing restart information for a serving GPRS support node (SGSN) at a gateway GPRS support node (GGSN), the restart information indicating whether the SGSN has been restarted;

receiving a packet data protocol (PDP) context message at the GGSN from the SGSN, the PDP context message including restart information indicating whether the SGSN has been restarted;

creating a response to the PDP context message at the GGSN;

transmitting the response to the SGSN from the GGSN;

comparing the restart information of the PDP context message received with the stored restart information stored for the SGSN at the GGSN; and

inactivating all subscriber contexts which are stored in the GGSN for use of the SGSN and have been updated before the latest restart of the SGSN when the restart information of the message received in the receiving step differs from the restart information stored for the SGSN.

2. A method according to claim 1, wherein said restart information comprises a restart counter value.

3. A method according to claim 2, wherein said restart counter value is compared with a stored restart counter value so as to determine said subscriber context updated before the latest restart.

4. A method according to claim 3, wherein said stored restart counter value is updated on the basis of said transmitted restart counter value.

5. A method according to claim 1, wherein said restart information is transmitted only one time after said latest restart.

6. A method according to claim 1, wherein said restart information is transmitted together with a tunnel management signaling message.

7. A method according to claim 1, wherein said PDP context message is a create or update PDP context request message.

8. A method according to claim 1, wherein the message received in the receiving step comprises a subscriber context create or update message.

9. A method according of claim 8, further comprising creating, as the response to the message, a subscriber context at the GGSN and transmitting a subscriber context response to the SGSN, wherein the subscriber context response includes the restart information indicating whether the GGSN has been restarted.

10. A system for restoring a subscriber context in a network element of a communication network comprising:

storing unit configured to store restart information for a serving GPRS support node (SGSN) at a gateway GPRS support node (GGSN) the restart information indicating whether the SGSN has been restarted;

receiving unit configured to receive a packet data protocol (PDP) context message at the GGSN from the SGSN-, the PDP context message including restart information indicating whether the SGSN has been restarted;

control unit configured to inactive all subscriber contexts which are stored in the GGSN related to the SGSN and have been updated before said latest restart, in response to said restart information;

transmitting unit configured to transmit a response message from the GGSN to the SGSN

restart counter configured to count a restart number and adding unit configured to add said restart number to a subscriber context message,

wherein the communication network includes at least the SGSN and the GGSN, the GGSN storing a plurality of subscriber contexts related to the SGSN.

11. A system according to claim 10, wherein said GGSN comprises a comparing unit configured to compare said restart number received with a restart number stored in a storing unit and to supply the comparing result to said control unit.

12. A system according to claim 10, wherein said control unit is configured to perform control so as to store a new subscriber context included in said subscriber context message and to delete an old subscriber context stored in said GGSN.

13. A system according to claim 10, wherein said transmitting unit comprises the restart counter configured to count a restart number, and wherein said control unit is configured to delete or inactivate corresponding subscriber contexts received before the latest restart.

14. A system according to claim 10, wherein said subscriber context is a PDP context.

15. A Serving GPRS Support Node (SGSN) for a mobile communication network, comprising:

transmitting unit configured to transmit a packet data protocol (PDP) context message from the SGSN to a gateway GPRS support node (GGSN), the PDP context message including restart information, the restart information indicating whether the SGSN has been restarted; and

receiving unit configured to receive a PDP context message from the GGSN, the PDP context message including restart information, the restart information indicating whether the GGSN has been restarted; and

control unit configured to inactivate all subscriber contexts stored in the SGSN for the GGSN and having been updated before said latest restart when the restart information of the message received from the GGSN differs from the restart information stored for the GGSN.

16. An SGSN according to claim 15, further comprising a restart counter for counting a restart number, and adding unit configured to add said restart number to the PDP context message.

17. An SGSN according to claim 15, wherein said PDP context message is a create or update PDP context message.

18. An SGSN according to claim 17, wherein said PDP context message is a create or update PDP context request message.

19. An SGSN according to claim 15, wherein said restart information comprises a restart number and wherein said SGSN comprises comparing unit configured to compare said restart number with a restart number stored in a storing unit and to supply the comparing result to said control unit.

20. An SGSN according to claim 15, wherein said SGSN is configured to add the restart information to the PDP context message only if the SGSN has been restarted and the SGSN sends the PDP context message to the GGSN for the first time after the restart.

21. A method for restoring a subscriber context in a mobile communication network, the method comprising:

storing, at a serving GPRS support node (SGSN), restart information for a gateway GPRS support node (GGSN) indicating whether the GGSN has been restarted;

receiving a packet data protocol (PDP) context message from the GGSN at the SGSN, wherein the PDP context message includes restart information;

comparing, at the SGSN, the restart information of the PDP context message with the restart information stored for the GGSN; and

inactivating all subscriber contexts that are stored in the SGSN for use of the GGSN except those subscriber contexts for use of the GGSN that have been updated after the latest restart of the GGSN when the restart information of the message received in the received PDP context message, differs from the restart information stored for the GGSN,

wherein the mobile communication network includes at least the SGSN and the GGSN, the SGSN storing a plurality of subscriber contexts for use of the GGSN, and the GGSN storing a plurality of subscriber contexts for use of the SGSN.

22. A Gateway GPRS Support Node (GGSN), for a mobile communication network, comprising:

transmitting unit configured to transmit a packet data protocol (PDP) context message from the GGSN to a serving GPRS support node (SGSN), the PDP context message including restart information, the restart information indicating whether the GGSN has been restarted;

receiving unit configured to receive a PDP context message from the SGSN, the PDP context message including restart information, the restart information indicating whether the SGSN has been restarted; and

control unit configured to inactivate all subscriber contexts which are stored in the GGSN for the SGSN and have been updated before the latest restart of the SGSN when the restart information of the message received in the receiving step differs from the restart information stored for the SGSN; and

to continue use of a received subscriber context created or updated after said latest restart.

23. The gateway GPRS support node (GGSN) of claim 22, wherein said PDP context message is a create or update PDP context message.

24. The gateway GPRS support node (GGSN) of claim 22, wherein said PDP context message is a create or update PDP context response message.