Method and apparatus for providing mobility within a network

• US 6,366,561 B1
• Filed: 11/30/1999
• Issued: 04/02/2002
• Est. Priority Date: 11/03/1999
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Bender, Paul E.
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US09/451,400
• Time in Patent Office: 854 Days
• Field of Search: 370/238, 370/254, 370/328, 370/409, 370/410, 370/420, 370/426, 455/433, 455/461, 379/114.27, 379/221.13
• US Class Current: 370/238
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/1446 wherein at least one of the networks is unlicensed
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

The present invention is a novel method and apparatus for providing transparent mobility of an entity within a network. The present invention allows a given entity, which has a communication path set up between it and a peer entity, to move from one location to another, without informing the peer entity of this movement, and without having the communication path broken. The present invention is applicable to decentralized networks using the IP protocol, and is particularly applicable on networks wherein it is desired that the mobility mechanism neither introduces latency nor decreases the available bandwidth of the network. In the present invention, neither is latency increased nor is bandwidth utilization increased, as is done in other mobility models. Additionally, the present invention utilizes standard protocols that are widely available from a plurality of equipment manufacturers on a variety of platforms. Thus, the present invention provides a very cost-effective model for network providers that need to support transparent mobility within their network.

Claims

1. In a decentralized serving network of a wireless telecommunications system, wherein said decentralized serving network comprises a plurality of entities and wherein a first entity of said plurality of entities contains an anchor point and wherein said decentralized serving network also comprises a plurality of routers, and wherein said decentralized serving network also comprises a plurality of service devices for providing standardized services for a plurality of access terminals, and wherein said anchor point is in communications with a service device of said plurality of service devices, a method for relocating said anchor point to a second entity of said plurality of entities, the method comprising the steps:

transmitting at least one relocation message between said first entity and said second entity;

copying a set of components of said anchor point from said first entity to said second entity, in accordance with said at least one relocation message; and

transmitting one or more standard routing messages from one or more entities of said plurality of entities, wherein said standard routing messages indicate to one or more routers of said plurality of routers that packets containing a destination address associated with said anchor point should be routed to said second entity.

2. The method of claim 1 wherein:

said first entity transmits a first relocation message to said second entity; and

said first relocation message contains component information utilized by said first entity in communications with said service device.

3. The method of claim 2 wherein said component information contains a first IP (Internet Protocol) address assigned to said anchor point.

4. The method of claim 3, the method further comprising the steps of:

said second entity receiving said first relocation message;

said second entity allocating resources for the creation of a local copy of said anchor point; and

said second entity initializing said resources in accordance with the information contained in said first relocation message.

5. The method of claim 4 wherein said decentralized serving network comprises a first transmitting entity, the method further comprising the steps of:

forming one or more first standard routing messages that indicate that IP packets having a destination address of said first IP address should be routed to said second entity; and

transmitting, from said first transmitting entity, said first standard routing messages to said one or more routers.

6. The method of claim 5 wherein said first transmitting entity is said second entity.

7. The method of claim 5 wherein said first standard routing message is an Open Shortest Path First (OSPF) message containing a cost for said first IP address that is lower than the cost of all other currently advertised routes for said first IP address.

8. The method of claim 6 further comprising the step of:

said second entity transmitting a second relocation message, based upon the expiration of a first period of time since said first standard routing message was either formed or transmitted.

9. The method of claim 8 further comprising the step of:

said second entity transmitting said second relocation message prior to said expiration of said first period of time, based upon said second entity receiving a packet having a destination IP address of said first IP address prior to said expiration of said first period of time.

10. The method of claim 9, wherein subsequent to the transmission of said second relocation message, and wherein said decentralized serving network comprises a second transmitting entity, the method further comprising the steps of:

forming one or more second standard routing messages that indicate that IP packets having a destination address of said first IP address associated with said anchor point should no longer be routed to said first entity; and

transmitting, from said second transmitting entity, said second standard routing messages to said one or more routers.

11. The method of claim 10 wherein said second transmitting entity is said first entity.

12. The method of claim 10 further comprising the steps of:

said first entity transmitting a third relocation message to said second entity; and

said third relocation message contain s said second IP address associated with said anchor point.

13. The method of claim 12, further comprising the step of:

deallocating the resources of said first entity that are associated with said anchor point.

14. The method of claim 12, the method further comprising the steps of:

said second entity receiving said third relocation message; and

said second entity completing configuration of said anchor point based upon the contents of said third relocation message.

15. The method of claim 13, wherein said decentralized serving network comprises a third transmitting entity, the method further comprising the steps of:

forming one or more third standard routing messages that indicate that IP packets having a destination address of said second IP address should be routed to said second entity; and

transmitting, from said third transmitting entity, said third standard routing messages to said one or more routers.

16. The method of claim 15 wherein said third standard routing message is an OSPF message containing a cost for said second IP address that is lower than the cost of all other currently advertised routes for said second IP address.

17. The e method of claim 15 further comprising the step of:

said second entity transmitting a set of zero or more resynchronization messages to an access terminal associated with said anchor point, based upon the expiration of a second period of time since said third standard routing message was either formed or transmitted.

18. The method of claim 17 further comprising the step of:

said second entity transmitting said set of resynchronization messages prior to said expiration of said second period of time, based upon said second entity receiving a packet having a destination IP address of said second IP prior to said expiration of said second period of time.

19. The method of claim 18, wherein when said first standard routing message or said third standard routing message is an OSPF message, the method further comprising the steps:

forming one or more fourth standard routing messages that indicate that although IP packets with destination addresses of said first IP address can still be routed to said second entity, the cost associated with said second entity delivering these packets to a destination of said first IP address will be higher than the cost said one or more routers currently associate with said second entity delivering packets to said first IP address;

said fourth standard routing messages are OSPF messages; and

transmitting said fourth standard routing messages to said one or more routers.

20. The method of claim 8 wherein said first standard routing message is a Mobile IP registration message.

21. The method of claim 17 wherein said third standard routing message is a Mobile IP registration message.

22. The method of claim 19 wherein said first entity is a first modem pool controller and wherein said second entity is a second modem pool controller, and wherein said anchor point is a dedicated controller.

23. In a telecommunications system, wherein said telecommunications system comprises a service device of a set of at least one service devices, and wherein said telecommunication system comprises a plurality of routers, a method for relocating an anchor point, contained within a first access point, to a second access point during or subsequent to a handoff, and wherein said anchor point is a dedicated controller, comprising the steps of:

transmitting at least one first relocation message from said first access point to said second access point, wherein said first relocation message contains dedicated controller component information associated with the connection to said at least one service devices;

allocating resources for a second dedicated controller at said second access point;

initializing said second dedicated controller with said component information; and

transmitting one or more OSPF messages from said second anchor point to one or more of said plurality of routers, wherein said OSPF messages indicate that packets containing a destination IP address associated with said dedicated controller can be delivered to said dedicated controller by said second access point with a lower cost than they would if said packets were delivered to said first access point.