Routing procedure for a communication system

• US 20040162077A1
• Filed: 04/18/2003
• Published: 08/19/2004
• Est. Priority Date: 02/19/2003
• Status: Active Grant

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Hulkkonen, Tony, Kauranen, Kari P.
• Granted Patent: US 7,415,274 B2
• Time in Patent Office: Days
• US Class Current: 455/445
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 8/18 Processing of user or subscriber data, e.g. subscribed services, user preferences or user profiles; Transfer of user or subscriber data
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points
• CPC Class Codes: H04W 92/02 Inter-networking arrangements
• CPC Class Codes: H04W 92/14 between access point controllers and backbone network device

Abstract

A mechanism for performing routing in a communication system including a radio access network and a plurality of core networks connected to the radio access network. In order to accomplish a mechanism whereby the routing of a registration request to a serving core network, and also the rejection of a registration request, can be carried out in a controlled manner, a core network is first selected for a registration request received. The registration request is then forwarded to the selected core network and, in response to at least one predetermined criterion being fulfilled, the selected core network is notified that the registration request is to be served by that core network, i.e. that the registration request cannot be rerouted to another core network.

Claims

1. A method for performing routing in a communication system including a radio access network and a plurality of core networks connected to the radio access network, the method comprising the steps of:

receiving a registration request in the radio access network;

selecting a core network for the registration request;

forwarding the registration request to the selected core network; and

in response to at least one predetermined criterion being fulfilled, notifying the selected core network that the registration request is to be served by the selected core network.

2. A method according to claim 1, further comprising the step of receiving a rerouting command from the selected core network, the re-routing command indicating that the registration request is to be routed to another core network.

3. A method according to claim 1, wherein the selecting and forwarding steps are repeated in response to the rerouting command, whereby another core network is selected for the registration request.

4. A method according to claim 3, further comprising the step of determining a set of core networks for serving the registration request, wherein the set indicates the core networks from among which a core network is selected for the registration request.

5. A method according to claim 4, further comprising the step of monitoring the number of core networks left in the set after the selecting step, wherein the at least one predetermined criterion is fulfilled when the number of core networks drops to zero.

6. A method according to claim 1, wherein the notifying step includes inserting an information element in a message carrying the registration request, the information element indicating that routing of the registration request to another core network is not allowed.

7. A method according to claim 6, wherein the information element is a cause Information Element (IE) according to a Radio Access Network Application Part (RANAP).

8. A method according to claim 2, wherein the notifying step includes sending a separate message to the selected core network, the message indicating that routing to another core network is not allowed.

9. A method according to claim 6, wherein the notifying step further includes sending a separate message to the selected core network, the message indicating that routing to another core network is not allowed.

10. A method according to claim 8, wherein the separate message is sent in response to the rerouting command.

11. A method according to claim 9, wherein the separate message is sent in response to the rerouting command.

12. A method according to claim 2, further comprising the step of inserting a cause value in the rerouting command, the cause value indicating why the registration request is to be routed to another network.

13. A method according to claim 1, further comprising the step of indicating the selected core network in the registration request, the selecting step being performed prior to the receiving step;

wherein the at least one predetermined criterion is fulfilled when the selected core network is indicated in the registration request.

14. A system for performing routing in a radio access network, the radio access network being connected to a plurality of core networks, the system comprising:

first interface means for receiving a registration request;

selection means for selecting a core network for the registration request;

transmission means for forwarding the registration request to the selected core network;

monitoring means for monitoring whether at least one predetermined criterion is fulfilled; and

notification means, responsive to the monitoring means, for notifying the selected core network that the registration request is to be served by the selected core network.

15. A system according to claim 14, further comprising second interface means for receiving a rerouting command from a core network.

16. A system according to claim 14, wherein the notification means are configured to insert an information element in a message carrying the registration request, the information element indicating that the registration request is to be served by the core network receiving the registration request.

17. A system according to claim 14, wherein the notification means are configured to send a separate message to the selected core network, the message indicating that the registration request is to be served by the core network receiving the registration request.

18. A system according to claim 16, wherein the notification means are further configured to send a separate message to the selected core network, the message indicating that the registration request is to be served by the core network receiving the registration request.

19. A system according to claim 14, wherein the first interface means and the selection means are in the radio access network.

20. A system according to claim 19, wherein the first interface means, the selection means, the transmission means, the monitoring means, and the notification means are fitted into a single network element.

21. A system according to claim 20, wherein the network element is a Radio Network Controller (RNC).

22. A system according to claim 14, wherein the first interface means are in the radio access network and selection means are in a mobile terminal configured to communicate with the radio access network, the selection means being configured to attach an indication of the selected core network to the registration request.

23. A core network element for a communication network, the communication network comprising a radio access network and a plurality of core networks, the core network element comprising:

a first interface means for receiving a registration request from a radio access network;

decision-making means, responsive to the first interface means, for deciding whether the registration request is to be served by the core network to which the core network element belongs;

transmission means, responsive to the decision-making means, for transmitting a rerouting command to the radio access network, the re-routing command indicating that the registration request is to be routed to another core network,

wherein the first interface means are configured to receive a notification notifying that a certain registration request is to be served by the core network to which the core network element belongs.

24. A core network element according to claim 23, wherein the transmission means are configured to insert a cause value in the re-routing command, the cause value indicating why the registration request is to be routed to another network.