Femtocell Integration into the Macro Network

• US 20080207170A1
• Filed: 02/06/2008
• Published: 08/28/2008
• Est. Priority Date: 02/26/2007
• Status: Active Grant

• Current Assignee: Ribbon Communications Operating Company, Inc. (Ribbon Communications, Inc.)
• Original Assignee: Kineto Wireless Incorporated (Ribbon Communications, Inc.)
• Inventors: Tao, Patrick, Gupta, Rajeev, Gallagher, Michael D., Markovic, Milan, Khetawat, Amit
• Granted Patent: US 8,019,331 B2
• Time in Patent Office: Days
• US Class Current: 455/411
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 60/005 Multiple registrations, e.g. multihoming
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

Some embodiments of the invention provide a communication system that includes a first communication network, a second communication network, and a core network. The second communication network includes a network controller and a group of two or more access areas that are communicatively coupled to the core network by the network controller. Some embodiments service the second network access areas by providing access area identifiers to each access area while communicating with the first network or core network using a single are identifier assigned to the network controller. Some embodiments provide access control by sending a series of invalid messages to a user equipment (UE) that is not authorized to access services of the second network to reject the UE. Some embodiments reject the UE by sending a message to ban a UE from an access area with a particular access area identifier.

Claims

1. For a communication system comprising a first communication network with a plurality of access areas, a second communication network with a plurality of access areas, and a core network communicatively coupled to the first and second networks, said second communication network comprising a network controller for communicatively coupling the plurality of second network access areas to the core network, a method comprising:

a) at the network controller, receiving a first area identifier for identifying an access area of the first communication network from a user equipment (UE) in a particular access area of the second network; and

b) from the network controller, sending a second area identifier to the core network before communicatively coupling said UE to the core network, wherein the second area identifier is for identifying each of the plurality of access areas of the second network when communicating with the core network.

2. The method of claim 1, wherein the second area identifier comprises the first area identifier and a third area identifier, wherein said third area identifier is used by the core network to route messages to and from the network controller.

3. The method of claim 2, wherein the first area identifier and the third area identifier comprise location area codes (LACs) for location areas of a UMTS or GSM network.

4. The method of claim 1, wherein the second network access area comprises an access point for communicatively coupling the UE to the network controller, the method further comprising sending a response comprising the second area identifier to the UE in the second network access area, wherein the access point receives the response from the network controller and replaces the second area identifier in the response with a third area identifier before sending said response to the UE.

5. The method of claim 1, wherein the first area identifier identifies an access area of the first network last visited by the UE.

6. For a communication system comprising a core network and a communication network, said communication network comprising a plurality of access points for establishing a plurality of access areas and a network controller for communicatively coupling the plurality of access areas to the core network, a method comprising:

a) at a particular access point, receiving a message comprising a first area identifier for identifying an access area of the particular access point;

b) at the particular access point, replacing the first area identifier with a second area identifier; and

c) passing the message with the second area identifier to the network controller for routing to the core network.

7. The method of claim 6, wherein the first and second area identifiers comprise location area codes (LACs) for location areas of a UMTS or GSM network, wherein the first area identifier is unique to area identifiers associated with other neighboring access areas of the communication network.

8. The method of claim 6 further comprising receiving at the particular access point, a response from the network controller comprising the second area identifier.

9. The method of claim 8 further comprising replacing at the particular access point, the second area identifier with the first area identifier before transmitting said response with the first area identifier to a user equipment in the access area.

10. The method of claim 8, wherein the response is routed from the network controller to the particular access point based on an international mobile subscriber identity (IMSI) associated with a user equipment in the access area of the particular access point for receiving said response.

11. The method of claim 6, wherein the second area identifier is for identifying the plurality of second network access areas as a single access area to the core network.

12. For a communication system comprising a core network and a communication network, said communication network comprising a set of access points for establishing a set of access areas and a network controller for communicatively coupling the set of access areas to the core network, a method comprising:

a) at an access point, receiving a message from a user equipment (UE) in an access area associated with the access point, said message for requesting access to services of the communication network from the access area;

b) at the access point, determining from the message that the UE is not authorized to access the services of the communication network from the access area; and

c) repeatedly passing a set of messages from the access point to the UE, wherein said repeated messages cause the UE to stop requesting access to the services of the communication network from the access area of the access point.

13. The method of claim 12, wherein the repeated passing of the set of messages comprises passing at least two messages from the access point to the UE, wherein said messages comprise at least one invalid parameter in each message.

14. The method of claim 12 further comprising monitoring a number of requests from the UE requesting access to the services of the communication network.

15. The method of claim 14 further comprising passing a message from the network controller to restrict the UE from reattempting to access the services of the communication network from the access area associated with the access point when the number of rejections exceeds a specified threshold.

16. The method of claim 15, wherein the access area has an associated area identifier, wherein the message to restrict the UE restricts the UE from accessing any access areas with the area identifier of the particular access area.

17. The method of claim 12, wherein the determining that the UE is not authorized comprises:

a) at the access point, identifying an international subscriber mobile identity (IMSI) of the UE from within the received message; and

b) at the access point, comparing the identified IMSI from the message to an allowed IMSI list to determine whether the UE is authorized to access the services of the communication network, wherein the allowed IMSI list specifies a list of IMSIs for UEs authorized to access the services of the communication network from the access area of the access point.

18. For a communication network comprising a set of access areas, wherein each access area is associated with an area identifier, a method for controlling access to the access areas, the method comprising:

a) receiving a message from a user equipment (UE) in a particular access area requesting access to services of the communication network, said request comprising an area identifier associated with the particular access area;

b) determining that said UE is not authorized to access the services of the communication network from the particular access area; and

c) sending a message to restrict said UE from requesting access to the services of the communication network from any access areas that specify the area identifier associated with the particular access area.

19. The method of claim 18 further comprising determining that other access areas of the second network do not specify the area identifier prior to sending the message to restrict said UE from the particular access area.

20. The method of claim 19 further comprising assigning a different area identifier to the particular access area prior to sending the message to restrict said UE from the particular access area when at least one other access area specifies the same area identifier, wherein sending the message to restrict said UE comprises sending the assigned different area identifier.

21. The method of claim 18, wherein the determining that said UE is not authorized to access the services of the communication network comprises determining a number of requests from the UE requesting access to the services of the communication network.

22. The method of claim 21, wherein the sending of the message to restrict the UE occurs when the number of requests from the UE exceeds a predetermined threshold.

23. The method of claim 18 further comprising, before sending the message to restrict the UE, determining whether the message from the UE specifies a request for emergency services and (i) providing the UE access to the services of the communication network when the message specifies a request for emergency services, and (ii) sending the message to restrict the UE when the message does not specify a request for emergency services.

24. The method of claim 18, wherein the communication network comprises a set of access points for establishing the access areas and a network controller for communicatively coupling the access areas to a core network, wherein a particular access point for the particular access area receives the message from the UE and the particular access point determines that the UE is not authorized for access.

25. The method of claim 24 further comprising from the particular access point sending a request to the network controller to cause the network controller to pass the message to restrict the UE from requesting access to the services of the communication network.