Handling of access capability information in a mobile network

1. A method of controlling communication of a user equipment in a mobile network with a plurality of access networks, the method comprising:

controlling, by a control node, access of the user equipment to that one of the access networks which is currently used by the user equipment, wherein the control node has functionality of either or both of a Mobility Management Entity (MME) and a Serving GPRS Support Node (SGSN);

determining, by the control node, an access capability of the user equipment in the access network currently used by the user equipment, the access capability comprising whether an IP Multimedia Subsystem (IMS) voice over Packet Switched (PS) session is supported; and

providing, by the control node, an indication of the determined access capability to a Home Subscriber Server (HSS) associated with a subscriber using the user equipment.

2. The method of claim 1 , wherein the indication is provided in response to the user equipment attaching to the mobile network or in response to the user equipment moving to said access network from another one of the access networks.

3. The method of claim 1 , wherein providing the indication to the subscriber database is responsive to determining that the access capability has changed.

4. The method of claim 1 , wherein the access capability further comprises one or more of:

whether circuit switched fallback for short message service is supported;

whether circuit switched fallback for voice service is supported;

whether idle mode signaling reduction is active or not.

5. A method of controlling communication of a user equipment in a mobile network, implemented by a Service Centralization and Continuity Application Server (SCC AS), the method comprising:

receiving, by the SCC AS from a Home Subscriber Server (HSS) associated with a subscriber using the user equipment, an indication of an access capability of the user equipment in that one of the access networks which is currently used by the user equipment, the access capability comprising whether an IP Multimedia Subsystem (IMS) voice over Packet Switched (PS) session is supported; and

controlling, by the SCC AS, termination of a connection to the user equipment based on the received indication.

6. The method of claim 5 , further comprising deciding, by the SCC AS, to terminate the connection based on the received indication, wherein the deciding comprises:

deciding to terminate the connection using the IMS voice over PS session responsive to the received indication indicating support of the IMS voice over PS session; or

deciding to terminate the connection using circuit switched access responsive to the received indication indicating no support of the IMS voice over PS session.

7. The method of claim 5 , further comprising the SCC AS requesting the indication by sending a message to the HSS.

8. The method of claim 5 , wherein the access capability further comprises one or more of:

whether circuit switched fallback for short message service is supported;

whether circuit switched fallback for voice service is supported;

whether idle mode signaling reduction is active or not.

9. A method of controlling communication of a user equipment in a mobile network, implemented by a Home Subscriber Server (HSS) associated with a subscriber using the user equipment, the method comprising:

receiving, by the HSS from a control node having functionality of either or both of a Mobility Management Entity (MME) and a Serving GPRS Support Node (SGSN), an indication of an access capability of the user equipment in that one of the access networks which is currently used by the user equipment, the access capability comprising whether an IP Multimedia Subsystem (IMS) voice over Packet Switched (PS) session is supported;

storing the indication in the HSS; and

transmitting the indication from the HSS to a Service Centralization and Continuity Application Server (SCC AS) configured to control termination of connections to the user equipment.

10. The method of claim 9 , wherein the access capability further comprises one or more of:

whether circuit switched fallback for short message service is supported;

whether circuit switched fallback for voice service is supported;

whether idle mode signaling reduction is active or not.

11. A control node in a mobile network with a plurality of access networks, the control node comprising:

networking circuitry configured to exchange signals within the mobile network;

processing circuitry communicatively coupled to the networking circuitry and configured to:

control access of a user equipment to that one of the access networks which is currently used by the user equipment;

determine an access capability of the user equipment in said access network currently used by the user equipment, the access capability comprising whether an IP Multimedia Subsystem (IMS) voice over Packet Switched (PS) session is supported;

transmit an indication of the determined access capability to an Home Subscriber Server (HSS) associated with a subscriber using the user equipment via the networking circuitry;

wherein the control node has functionality of either or both of a Mobility Management Entity (MME) and a Serving GPRS Support Node (SGSN).

12. The control node of claim 11 , wherein the processing circuitry is configured to transmit the indication in response to the user equipment attaching to the mobile network or in response to the user equipment moving to said access network from another one of the access networks.

13. The control node of claim 11 , wherein the processing circuitry is configured to transmit the indication in response to determining that the access capability has changed.

14. The control node of claim 11 , wherein the access capability further comprises one or more of:

whether circuit switched fallback for short message service is supported;

whether circuit switched fallback for voice service is supported;

whether idle mode signaling reduction is active or not.

15. A Service Centralization and Continuity Application Server (SCC AS) in a mobile network, the SCC AS comprising:

networking circuitry configured to exchange signals within the mobile network;

processing circuitry communicatively coupled to the networking circuitry and configured to:

receive, from a Home Subscriber Server associated with a subscriber using the user equipment via the networking circuitry, an indication of an access capability of the user equipment in that one of the access networks which is currently used by the user equipment, the access capability comprising whether an IP Multimedia Subsystem (IMS) voice over Packet Switched (PS) session is supported;

control termination of a connection to the user equipment based on the received indication.

16. The SCC AS of claim 15 , wherein the processing circuitry is further configured to decide to terminate the connection based on the received indication, wherein to decide the processing circuitry is configured to:

decide to terminate the connection using IMS voice over PS session responsive to the received indication indicating support of IMS voice over PS session; or

decide to terminate the connection using circuit switched access responsive to the received indication indicating no support of IMS voice over PS session.

17. The SCC AS of claim 15 , wherein the access capability further comprises one or more of:

whether circuit switched fallback for short message service is supported;

whether circuit switched fallback for voice service is supported;

whether idle mode signaling reduction is active or not.

18. A Home Subscriber Server (HSS) in a mobile network, the HSS comprising:

networking circuitry configured to exchange signals within the mobile network;

processing circuitry communicatively coupled to the networking circuitry and configured to:

receive an indication of an access capability of a user equipment from a control node having functionality of either or both of a Mobility Management Entity (MME) and a Serving GPRS Support Node (SGSN), the access capability comprising whether an IP Multimedia Subsystem (IMS) voice over Packet Switched (PS) session is supported;

store the indication;

transmit the indication, via the networking circuitry, to a Service Centralization and Continuity Application Server (SCC AS) configured to control termination of a connection to the user equipment.

19. The HSS of claim 18 , wherein the access capability further comprises one or more of:

whether circuit switched fallback for short message service is supported;

whether circuit switched fallback for voice service is supported;

whether idle mode signaling reduction is active or not.