RF-aware packet filtering in radio access networks that employ circuit switching

• US 20060050668A1
• Filed: 09/03/2004
• Published: 03/09/2006
• Est. Priority Date: 09/03/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Harper, Matthew H., Puthiyandyil, Sanil Kumar
• Granted Patent: US 8,175,534 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/74 measures in reaction to resource unavailability
• CPC Class Codes: H04L 63/0254 Stateful filtering
• CPC Class Codes: H04W 12/088 using filters or firewalls
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]

Abstract

Methods and systems are provided for filtering packets in a wireless communication system in the to-mobile subscriber direction. This filtering is at least in part based on RF circuit state information. For example, a packet filter is used that either permits or denies packets from reaching a mobile subscriber based on whether there is already an established RF circuit to provide packets to the mobile subscriber. Alternatively, or in addition, the packet filter may consider the history of circuit state transitions associated with a particular mobile subscriber, the percentage (or aggregate number) of available airlink resources that are currently in use, and/or the length of time associated with the dormancy of a mobile subscriber'"'"'s RF connection. In various embodiments, the packet filter may cause one or more packets to be sent to a mobile subscriber using a special data channel that does not require the establishment of an RF circuit.

Claims

1. A wireless communication system comprising:

a radio access network (RAN);

a network access server (NAS) for providing an interface between the RAN and an internet protocol (IP) network; and

a data packet filter for selectively permitting the passage of a data packet from the IP network to the RAN at least in part based on radio frequency (RF) circuit state information concerning a mobile subscriber (MS) that communicates with the RAN using an airlink.

2. The wireless communication system of claim 1, wherein the RAN comprises a base transceiver station (BTS), a base station controller (BSC), and a packet control function (PCF).

3. The wireless communication system of claim 2, wherein the BSC and the PCF are co-located.

4. The wireless communication system of claim 1, wherein the NAS is a packet data service node (PDSN).

5. The wireless communication system of claim 1, wherein the NAS is a gateway general packet radio service support node (GGSN).

6. The wireless communication system of claim 1, wherein the RF circuit state information comprises information regarding whether an RF circuit is currently established in connection with the MS.

7. The wireless communication system of claim 6, wherein the data packet filter permits the passage of the data packet from the IP network to the RAN when an RF circuit is currently established in connection with the MS.

8. The wireless communication system of claim 6, wherein the data packet filter denies the passage of the data packet from the IP network to the RAN when an RF circuit is not currently established in connection with the MS.

9. The wireless communication system of claim 1, wherein the RF circuit state information comprises information regarding the number of circuit state transitions that have occurred in connection with the MS over a predetermined, past period of time.

10. The wireless communication system of claim 9, wherein the data packet filter permits the passage of the data packet from the IP network to the RAN when the number of circuit state transitions is below a predetermined number.

11. The wireless communication system of claim 9, wherein the data packet filter denies the passage of the data packet from the IP network to the RAN when the number of circuit state transitions is above a predetermined number.

12. The wireless communication system of claim 1, wherein the RF circuit state information comprises information regarding the amount of time that the MS has been RF-dormant.

13. The wireless communication system of claim 1, wherein the data packet filter is located within the NAS.

14. The wireless communication system of claim 1, wherein the data packet filter is located within a firewall device.

15. The wireless communication system of claim 14, wherein the data packet filter is located in the data path between the IP network and the NAS.

16. A wireless communication system comprising:

a radio access network (RAN);

a network access server (NAS) for providing an interface between the RAN and an internet protocol (IP) network; and

a data packet filter for selectively permitting the passage of a data packet from the IP network to the RAN at least in part based on a determined usage of available radio frequency (RF) resources in the wireless communication system.

17. The wireless communication system of claim 16, further comprising a mobile subscriber (MS) that communicates with the RAN using an airlink, the MS that receives the data packet from the IP network when permitted by the data packet filter.

18. The wireless communication system of claim 16, wherein the RAN comprises a base transceiver station (BTS), a base station controller (BSC), and a packet control function (PCF).

19. The wireless communication system of claim 16, wherein the NAS is a packet data service node (PDSN).

20. The wireless communication system of claim 16, wherein the NAS is a gateway general packet radio service support node (GGSN).

21. The wireless communication system of claim 16, wherein the data packet filter denies the passage of the data packet from the IP network to the RAN when the total number of available RF resources that are being used is above a predetermined number.

22. The wireless communication system of claim 16, wherein the data packet filter denies the passage of the data packet from the IP network to the RAN when the percentage of available RF resources that are being used is above a predetermined number.

23. A wireless communication system comprising:

a radio access network (RAN);

a network access server (NAS) for providing an interface between the RAN and an internet protocol (IP) network; and

a data packet filter for selectively marking and permitting the passage of a data packet from the IP network to the RAN, the marking resulting in the data packet being sent to a mobile subscriber (MS) using a special data channel.

24. The wireless communication system of claim 23, wherein the marking is performed when the MS is RF-dormant.

25. The wireless communication system of claim 23, wherein the special data channel is a code-divisional multiple access (CDMA) short data burst channel.

26. The wireless communication system of claim 23, wherein the marking is performed by altering the IP header of the data packet.

27. The wireless communication system of claim 23, wherein the marking is performed by toggling the GRE header of the data packet.

28. A method for filtering data packets in a wireless communication system that comprises a radio access network (RAN), a network access server (NAS), and an internet protocol (IP) network, the method comprising:

receiving one or more data packets destined for a mobile subscriber (MS) from the IP network;

determining radio frequency (RF) circuit state information concerning at least one of the MS and the wireless communication system; and

permitting or denying the passage of the one or more packets from the IP network to the MS based at least in part based on the determined RF circuit state information.

29. The method of claim 28, wherein the determining comprises obtaining information regarding whether an RF circuit is currently established in connection with the MS.

30. The method of claim 28, wherein the permitting or denying comprising permitting the passage of the data packet from the IP network to the RAN when an RF circuit is currently established in connection with the MS.

31. The method of claim 28, wherein the permitting or denying comprising denying the passage of the data packet from the IP network to the RAN when no RF circuit is currently established in connection with the MS.

32. The method of claim 28, wherein the determining comprises obtaining information regarding the number of circuit state transitions that have occurred in connection with the MS over a predetermined, past period of time.

33. The method of claim 28, wherein the wherein the permitting or denying comprising permitting the passage of the data packet from the IP network to the RAN when the number of circuit state transitions is below a predetermined number.

34. The method of claim 28, wherein the wherein the permitting or denying comprising denying the passage of the data packet from the IP network to the RAN when the number of circuit state transitions is above a predetermined number.

35. The method of claim 28, wherein the determining comprises obtaining information regarding the amount of time that the MS has been RF-dormant.

36. A method for filtering data packets in a wireless communication system that comprises a radio access network (RAN), a network access server (NAS), and an internet protocol (IP) network, the method comprising:

receiving one or more data packets destined for a mobile subscriber (MS) from the IP network;

determining whether the MS is RF-dormant; and

when the MS is RF-dormant, marking the one or more data packets from the IP network, the marking resulting in the one or more data packets being sent to the MS using a special data channel.

37. A wireless communication system comprising:

means for receiving one or more data packets destined for a mobile subscriber (MS) from an internet protocol (IP) network;

means for determining radio frequency (RF) circuit state information concerning at least one of the MS and the wireless communication system; and

means for permitting or denying the passage of the one or more packets from the IP network to the MS based at least in part on the determined RF circuit state information.

38. A data packet filter for use in a wireless communication system, the data packet filter receiving one or more data packets from an internet protocol (IP) network and, based at least in part on radio frequency (RF) circuit state information concerning at least one of a mobile subscriber (MS) and the wireless communication system, permitting or denying the passage of the one or more packets from the IP network to the MS.