RADIO ACCESS NETWORK (RAN) LEVEL KEEP ALIVE SIGNALING

• US 20090197589A1
• Filed: 01/30/2009
• Published: 08/06/2009
• Est. Priority Date: 02/02/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Kitazoe, Masato
• Granted Patent: US 8,477,811 B2
• Time in Patent Office: Days
• US Class Current: 455/422.1
• CPC Class Codes: H04W 76/25 Maintenance of established connections

Abstract

In a wireless communication system, a mobile station performs “keep-alive” signaling with a serving radio access network (RAN), transmitting its identity without necessarily an accompanying data portion. The serving RAN does not necessarily acknowledge. Thereby, the mobile station maintains state synchronization with the serving RAN, which also benefits in being able to timely release a context when the “keep-alive” transmission is not continued. In one aspect, the mobile station utilizes random access procedures (RACH) for uplink data arrival with a 0-byte MAC buffer status report whose identifying Cell Radio Network Temporary Identity (C-RNTI) can be used by the serving RAN for keep alive purposes. In another aspect, the mobile station can perform non-access stratum (NAS) signaling containing identification for the mobile station that is supported by underlying access stratum (AS) signaling via the serving RAN. This identifying NAS signaling is detected or a downstream recipient alerts the serving RAN.

Claims

1. A method for keep alive signaling to a radio access network (RAN), comprising:

determining that no data is queued for transmission to a serving radio access network; and

maintaining state synchronization with the serving radio access network by periodically transmitting an identifying signal without accompanying layer 3 signaling data, prompting maintenance of context.

2. The method of claim 1, further comprising:

determining that data is queued for transmission to the serving radio access network; and

transmitting the data by performing Evolved Universal Mobile Telecommunications System Terrestrial Radio Access Network (E-UTRAN) protocol.

3. The method of claim 2, further comprising transmitting a radio resource control (RRC) message, prompting reset of a timer by the serving radio access network.

4. The method of claim 1, further comprising periodically transmitting the identifying signal by transmitting a medium access control (MAC) buffer status report and comprises identifying Cell Radio Network Temporary Identity (C-RNTI).

5. The method of claim 1, further comprising transmitting an access stratum (AS) transmission to the serving radio access network supporting a non-access stratum layer comprising the identifying signal.

6. The method of claim 5, further comprising transmitting the non-access stratum layer signaling by transmitting a periodic tracking area update.

7. The method of claim 5, further comprising transmitting the non-access stratum layer signaling that triggers a medium access control (MAC) buffer status report for the serving radio access network to detect the identifying signal.

8. The method of claim 5, further comprising transmitting the non-access stratum layer signaling that triggers a medium access control (MAC) buffer status report for the serving radio access network to receive the identifying signal from a downstream recipient.

9. The method of claim 1, further comprising selecting one of a plurality of options for keep alive signaling by,

transmitting a non-access stratum periodic tracking area update with mobile station identification to a mobility management entity via the serving radio access network in response to a determination of a reporting requirement;

transmitting medium access control (MAC) message in response to a determination that data is to be transmitted on an uplink to the serving radio access network; and

transmitting a MAC buffer status report for uplink data arrival in response to a determination of no data queued for uplink transmission.

10. The method of claim 1, further comprising periodically transmitting the identifying signal based upon a timer without receiving an acknowledgement from the serving radio access network.

11. At least one processor for keep alive signaling to a radio access network (RAN), comprising:

a first module for determining that no data is queued for transmission to a serving radio access network; and

a second module for maintaining state synchronization with the serving radio access network by periodically transmitting an identifying signal without accompanying data, prompting maintenance of context.

12. A computer program product for keep alive signaling to a radio access network (RAN), comprising:

a computer-readable storage medium comprising,

a first set of codes for causing a computer to determine that no data is queued for transmission to a serving radio access network; and

a second set of codes for causing the computer to maintain state synchronization with the serving radio access network by periodically transmitting an identifying signal without accompanying data, prompting maintenance of context.

13. An apparatus for keep alive signaling to a radio access network (RAN), comprising:

means for determining that no data is queued for transmission to a serving radio access network; and

means for maintaining state synchronization with the serving radio access network by periodically transmitting an identifying signal without accompanying data, prompting maintenance of context.

14. An apparatus for keep alive signaling to a radio access network (RAN), comprising:

a computing platform for determining that no data is queued for transmission to a serving radio access network; and

a transmitter for maintaining state synchronization with the serving radio access network by periodically transmitting an identifying signal without accompanying data, prompting maintenance of context.

15. The apparatus of claim 14, wherein the computing platform is further for determining that data is queued for transmission to the serving radio access network, and wherein the transmitter is further for transmitting the data.

16. The apparatus of claim 15, further comprising transmitting a radio resource control (RRC) message, prompting reset of a timer by the serving radio access network.

17. The apparatus of claim 14, further comprising periodically transmitting the identifying signal by transmitting a medium access control (MAC) buffer status report and comprises identifying Cell Radio Network Temporary Identity (C-RNTI).

18. The apparatus of claim 14, further comprising transmitting an access stratum (AS) transmission to the serving radio access network supporting a non-access stratum layer comprising the identifying signal.

19. The apparatus of claim 18, further comprising transmitting the non-access stratum layer signaling by transmitting a periodic tracking area update.

20. The apparatus of claim 18, further comprising transmitting the non-access stratum layer signaling that triggers a medium access control (MAC) buffer status report for the serving radio access network to detect the identifying signal.

21. The apparatus of claim 18, further comprising transmitting the non-access stratum layer signaling that triggers a medium access control (MAC) buffer status report for the serving radio access network to receive the identifying signal from a downstream recipient.

22. The apparatus of claim 14, further comprising selecting one of a plurality of options for keep alive signaling by,

transmitting a non-access stratum periodic tracking area update with mobile station identification to a mobility management entity via the serving radio access network in response to a determination of a reporting requirement;

transmitting medium access control (MAC) message in response to a determination that data is to be transmitted on an uplink to the serving radio access network; and

transmitting a MAC buffer status report for uplink data arrival in response to a determination of no data queued for uplink transmission.

23. The apparatus of claim 14, wherein the transmitter is further for periodically transmitting the identifying signal based upon a timer without receiving an acknowledgement from the serving radio access network.

24. A method for receiving keep alive signaling from mobile station at a radio access network (RAN), comprising:

periodically receiving an identifying signal without accompanying data from a mobile station;

resetting a keep alive timer for the mobile station based upon the identifying signal; and

maintaining context for the mobile station.

25. The method of claim 24, further comprising:

receiving data from the mobile station; and

resetting the keep alive timer for the mobile station based upon determining identification of the mobile station from the received signaling data.

26. The method of claim 25, further comprising receiving signaling data by receiving a radio resource control (RRC) message from the mobile station.

27. The method of claim 24, further comprising periodically receiving the identifying signal by receiving a medium access control (MAC) buffer status report and comprises identifying Cell Radio Network Temporary Identity (C-RNTI).

28. The method of claim 24, further comprising:

receiving an access stratum (AS) transmission from the mobile station; and

relaying a non-access stratum layer signaling accompanied by the identifying signal and supported by the AS transmission to a downstream recipient.

29. The method of claim 28, further comprising receiving the non-access stratum layer by receiving a periodic tracking area update.

30. The method of claim 28, further comprising detecting the identifying signal attached to the non-access stratum layer signaling at the serving radio access network.

31. The method of claim 28, further comprising receiving the attached identifying signal from the downstream recipient of the non-access stratum layer.

32. The method of claim 24, further comprising responding to a selected one of a plurality of options for keep alive signaling exercised by the mobile station by,

receiving the identifying signal by receiving a non-access stratum periodic tracking area update from the mobile station;

receiving the identifying signal by receiving a medium access control (MAC) message; and

receiving a MAC buffer status report for uplink data arrival.

33. The method of claim 24, further comprising:

periodically receiving the identifying signal; and

resetting the keep alive timer without acknowledging receipt of the identifying signal to the mobile station.

34. The method of claim 24, further comprising:

periodically receiving the identifying signal; and

acknowledging receipt of the identifying signal to the mobile station.

35. At least one processor for receiving keep alive signaling from mobile station at a radio access network (RAN), comprising:

a first module for periodically receiving an identifying signal without accompanying data from a mobile station;

a second module for resetting a keep alive timer for the mobile station based upon the identifying signal; and

a third module for maintaining context for the mobile station.

36. A computer program product for receiving keep alive signaling from mobile station at a radio access network (RAN), comprising:

a computer-readable storage medium comprising,

a first set of codes for causing a computer to periodically receive an identifying signal without accompanying data from a mobile station;

a second set of codes for causing the computer to reset a keep alive timer for the mobile station based upon the identifying signal; and

a third set of codes for causing the computer to maintain context for the mobile station.

37. An apparatus for receiving keep alive signaling from mobile station at a radio access network (RAN), comprising:

means for periodically receiving an identifying signal without accompanying data from a mobile station;

means for resetting a keep alive timer for the mobile station based upon the identifying signal; and

means for maintaining context for the mobile station.

38. An apparatus for receiving keep alive signaling from mobile station at a radio access network (RAN), comprising:

a receiver for periodically receiving an identifying signal without accompanying data from a mobile station; and

a computing platform for resetting a keep alive timer for the mobile station based upon the identifying signal and for maintaining context for the mobile station.

39. The apparatus of claim 38, wherein the receiver is further for receiving data from the mobile station by decoding signaling date, and the computing platform is further for resetting the keep alive timer for the mobile station based upon determining identification of the mobile station from the received signaling data.

40. The apparatus of claim 39, wherein the receiver is further for receiving signaling data by receiving a radio resource control (RRC) message from the mobile station.

41. The apparatus of claim 38, wherein the receiver is further for periodically receiving the identifying signal by receiving a medium access control (MAC) buffer status report and comprises identifying Cell Radio Network Temporary Identity (C-RNTI).

42. The apparatus of claim 38, wherein the receiver is further for receiving an access stratum (AS) transmission from the mobile station, and wherein the computing platform is further for relaying a non-access stratum layer signaling accompanied by the identifying signal and supported by the AS transmission to a downstream recipient.

43. The apparatus of claim 42, wherein the receiver is further for receiving the non-access stratum layer by receiving a periodic tracking area update.

44. The apparatus of claim 42, wherein the computing platform is further for detecting the identifying signal attached to the non-access stratum layer signaling at the serving radio access network.

45. The apparatus of claim 42, wherein the receiver is further for receiving the identifying signal from the downstream recipient of the non-access stratum layer.

46. The apparatus of claim 38, wherein the computing platform is further for responding to a selected one of a plurality of options for keep alive signaling exercised by the mobile station, and

wherein the receiver is further for receiving the identifying signal by receiving a non-access stratum periodic tracking area update from the mobile station, for receiving the identifying signal by receiving a medium access control (MAC) message, and for receiving a MAC buffer status report for uplink data arrival.

47. The apparatus of claim 38, wherein the receiver is further for periodically receiving the identifying signal, and wherein the computing platform is further for resetting the keep alive timer without acknowledging receipt of the identifying signal to the mobile station.

48. The apparatus of claim 38, wherein the receiver is further for periodically receiving the identifying signal, and wherein the computing platform is further for acknowledging receipt of the identifying signal to the mobile station.