Server component network resource allocation for handoff between mobile switching center packet-switched portion and mobile switching center circuit-switched portion

1. An apparatus, comprising:

a server component that sends one or more session initiation protocol (SIP) messages, to cause an allocation of one or more network resources for an active call terminated to a mobile telephone without session description protocol (SDP) information, upon initiation of a handoff of the active call between a packet-switched portion of a mobile switching center and a circuit-switched portion of a mobile switching center, wherein the one or more network resources provide a translation between the packet-switched portion of the mobile switching center and the circuit-switched portion of the mobile switching center.

2. The apparatus of claim 1 , wherein the handoff of the active call comprises a handoff from the packet-switched portion of the mobile switching center to the circuit-switched portion of the mobile switching center;

wherein the server component comprises a portion of the mobile switching center that comprises the packet-switched portion;

wherein the server component sends one or lucre session initiation protocol UPDATE messages to configure one or more session initiation protocol endpoints for the handoff from the packet-switched portion of the mobile switching center to the circuit-switched portion of the mobile switching center.

3. The apparatus of claim 2 , wherein the server component employs one or more ANSI-41 signals to communicate with the mobile switching center that comprises the circuit-switched portion.

4. The apparatus of claim 2 , wherein the mobile switching center that comprises the packet-switched portion and the mobile switching center that comprises the circuit-switched portion comprise a same mobile switching center.

5. The apparatus of claim 2 , wherein the server component signals to configure the one or more session initiation protocol endpoints upon initiation of a handback of the active call from the circuit-switched portion of the mobile switching center to the packet-switched portion of the mobile switching center;

wherein the server component signals to release one or more of the one or more network resources upon the initiation of the handback from the circuit-switched portion of the mobile switching center to the packet-switched portion of the mobile switching center.

6. The apparatus of claim 5 , wherein the sewer component employs one or more ANSI-41 signals to communicate with the mobile switching center that comprises the circuit-switched portion.

7. The apparatus of claim 5 , wherein the mobile switching center that comprises the packet-switched portion and the mobile switching center that comprises the circuit-switched portion comprise a same mobile switching center.

8. The apparatus of claim 1 , wherein the handoff of the active call comprises a handoff from the circuit-switched portion of the mobile switching center to the packet-switched portion of the mobile switching center;

wherein the server component comprises a portion of the mobile switching center that comprises the packet-switched portion.

9. The apparatus of claim 8 , wherein the server component employs one or more ANSI-41 signals to communicate with the mobile switching center that comprises the circuit-switched portion.

10. The apparatus of claim 8 , wherein the mobile switching center that comprises the packet-switched portion and the mobile switching center that comprises the circuit-switched portion comprise a same mobile switching center.

11. The apparatus of claim 8 , wherein the server component signals to release the one or more network resources upon initiation of a handback from the packet-switched portion of the mobile switching center to the circuit-switched portion of the mobile switching center.

12. The apparatus of claim 11 , wherein the server component employs one or more ANSI-41 signals to communicate with the mobile switching center that comprises the circuit-switched portion.

13. The apparatus of claim 11 , wherein the mobile switching center that comprises the packet-switched portion and the mobile switching center that comprises the circuit-switched portion comprise a same mobile switching center.

14. A method, comprising the steps of:

performing a handoff of an active call to a mobile telephone between a packet-switched portion of a mobile switching center and a circuit-switched portion of a mobile switching center;

sending a session initiation protocol (SIP) message without session description protocol (SDP) information to cause an allocation of one or more network resources that provide a translation between the packet-switched portion of the mobile switching center and the circuit-switched portion of the mobile switching center;

performing a handback of the active call between the packet-switched portion of the mobile switching center and the circuit-switched portion of the mobile switching center; and

sending a signal to cause a release of one or more of the one or more network resources.

15. The method of claim 14 , wherein the step of performing the handoff of the active call to the mobile telephone between the packet-switched portion of the mobile switching center and the circuit-switched portion of the mobile switching center comprises the steps of:

sending a session initiation protocol UPDATE message to cause a configuration of one or more session initiation protocol endpoints to support the handoff of the active call from the packet-switched portion of the mobile switching center to the circuit-switched portion of the mobile switching center; and

sending a signal to cause an activation of the one or more network resources.

16. The method of claim 15 , further comprising the step of:

sending one or more ANSI-41 signals to and receiving one or more ANSI-41 signals from the mobile switching center that comprises the circuit-switched portion.

17. The method of claim 15 , wherein the session initiation protocol endpoint comprises a first media port for the active call, wherein the step of sending the signal to configure the one or more session initiation protocol endpoints to support the handoff of the active call from the packet-switched portion of the mobile switching center to the circuit-switched portion of the mobile switching center comprises the steps of:

sending a session initiation protocol message to cause a configuration of a second media port of the session initiation protocol endpoint;

sending a session initiation protocol message to cause the session initiation protocol endpoint to establish a connection between the second media port and the one or more network resources;

sending a session initiation protocol message to cause an activation of the second media port; and

sending a session initiation protocol message to cause a release of the first media port of the session initiation protocol endpoint.

18. The method of claim 14 , further comprising the step of:

sending one or more ANSI-41 signals to and receiving one or more ANSI-41 signals from the mobile switching center that comprises the circuit-switched portion to support the handoff from the circuit-switched portion of the mobile switching center to the packet-switched portion of the mobile switching center.

19. An article, comprising:

one or more computer-readable signal-bearing media; and

means in the one or more media for performing a handoff of an active call to a mobile telephone between a packet-switched portion of a mobile switching center and a circuit-switched portion of a mobile switching center;

means in the one or more media for sending a session initiation protocol message without session description protocol (SDP) information to cause an allocation of one or more network resources that provide a translation between the packet-switched portion of the mobile switching center and the circuit-switched portion of the mobile switching center;

means in the one or more media for performing a handback of the active call between the packet-switched portion of the mobile switching center and the circuit-switched portion of the mobile switching center; and

means in the one or more media for sending a signal to cause a release of one or more of the one or more network resources.

20. The article of claim 19 , further comprising:

means in the one or more media for sending one or more ANSI-41 signals to and receiving one or more ANSI-41 signals from the mobile switching center that comprises the circuit-switched portion to support the handoff.