Support of disparate addressing plans and dynamic HA address allocation in mobile IP

• US 20030223439A1
• Filed: 04/07/2003
• Published: 12/04/2003
• Est. Priority Date: 04/08/2002
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: OʼNeill, Alan
• Granted Patent: US 7,356,020 B2
• Time in Patent Office: Days
• US Class Current: 370/402
• CPC Class Codes: H04L 61/2503 Translation of Internet protocol [IP] addresses
• CPC Class Codes: H04W 8/065 involving selection of the user mobility server
• CPC Class Codes: H04W 8/08 Mobility data transfer
• CPC Class Codes: H04W 8/085 involving hierarchical organized mobility servers, e.g. hierarchical mobile IP [HMIP]
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

Methods and apparatus for enhancing Mobile IP signaling and to support use of disparate addressing plans and dynamic Home Agent allocation in Mobile IP Regional Tunneling are described. The enhanced methods of signaling use an intermediate node, e.g., a Gateway Foreign Agent, straddling different addressing domains, when the signaling controls a process between the intermediate node and an upstream node. The specific intermediate node, its interfaces and upstream addresses can be dynamically selected. The Enhanced MIP signaling includes dynamic allocation of: a regional node at a Foreign Agent, the upstream address of a regional node by the regional node, a Home Agent for a regional node prior to dynamic allocation of the regional node. A method is supported to indicate to a Mobile Node that a dynamically allocated regional node has become invalid triggering enhanced MIP signaling dynamically allocating a new regional node and upstream interface address.

Claims

1. A communications method for use in a communications system including a first and a second network address domains and an intermediate node, said intermediate node including first and second interfaces, said first interface having a first network address routable in the first network address domain, said second interface having a second network address routable in said second network address domain, said first and second network addresses being different, said system further including a downstream node with an interface and a network address in the first domain, and an upstream node including an interface and a network address in the second domain, the method comprising the steps of:

operating said intermediate node to receive a first message from said downstream node, said first message including a first message body and a first header, said first message body including at least one instruction used to control said upstream node to interact with said intermediate node, said first header including the first network address as the destination address of said first message; and

operating said intermediate node to generate a second message including a second message body and a second header, said second message body including said at least one instruction from said downstream node and said second address corresponding to said second interface, said second address being for use by said upstream node when interacting with said intermediate node in accordance with said at least one instruction, said second header including a destination address corresponding to said upstream node.

2. The method of claim 1, wherein the first and second message bodies include the first network address of said first network interface of said intermediate node.

3. The method of claim 2, wherein said second network address is included in said first message body, said step of generating said second message including incorporating said second network address from said first message body into said second message body.

4. The method of claim 1, wherein said first message body includes a blank intermediate node address field and wherein said second network address is added to said second message body by said intermediate node thereby resulting in said first and second message bodies including different intermediate node address fields.

5. The method of claim 1, wherein second network address is selected from a plurality of network addresses as a function of the destination address corresponding to said upstream node.

6. The method of claim 1, wherein said first and second messages are mobile IP messages.

7. The method of claim 1, wherein said at least one instruction is used in establishing a tunnel between the upstream node and the intermediate node.

8. The method of claim 6, wherein the first address is included in a mobile IP extension included in said first message body and said second address is included in a mobile IP message extension included in said second message body.

9. The method of claim 6, wherein said upstream node is mobile IP home agent.

10. The method of claim 9, wherein said downstream node is a mobile IP foreign agent.

11. The method of claim 10, wherein said intermediate node is a mobile IP regional node, said regional node being one of a gateway foreign agent, a hierarchal foreign agent and a local home agent.

12. The method of claim 11, wherein the system further comprises a mobile node, the method further comprising:

sending a message from the foreign agent to the mobile node identifying an IP address of a default regional node for the purposes of regional movement detection;

sending a message from the foreign agent to the mobile node that informs the mobile node of the allocation of a regional node that is not the default node, and

sending a regional registration message to the assigned regional node only whilst the default regional node received from the foreign agent is unchanged.

13. The method of claim 11, further comprising:

detecting the change in the default regional node advertised by the foreign agent;

sending a mobile IP registration message to the home agent from the mobile node via the foreign agent, said registration message including a preliminary care of address field;

dynamically assigning a regional node at the foreign agent, having a regional node IP address,

dynamically assigning a regional node care of address at the regional node,

including the dynamically assigned care of address into the body of said registration message sent to the home agent; and

installing a mobile IP binding at the home agent between a home address of the mobile node and the care of address of the regional node.

14. The method of claim 13, further comprising:

operating the home agent, GFA and FA to securely communicate the dynamically assigned regional node IP address and the dynamically assigned regional node care of address back to the mobile node in the Registration Reply message.

15. The method of claim 11, further comprising the step of:

communicating a mobile IP registration message to an as yet to be allocated home agent;

dynamically allocating a home agent address at the foreign agent,

including in the body of the first message sent from the foreign agent to the regional node, the dynamically assigned home agent address, and

wherein the destination address of said second message is said dynamically assigned home agent address.

16. The method of claim 6, wherein said upstream node is a mobile IP regional node and the intermediate node is a MIP foreign agent

17. The method of claim 6, wherein said downstream node is a Mobile IP Mobile Node, the intermediate node is a MIP regional node and the upstream node is a MIP home agent.

18. A communications system comprising:

first and second network address domains;

an intermediate node, said intermediate node including first and second interfaces, said first interface having a first network address routable in the first network address domain, said second interface having a second network address routable in said second network address domain said first and second network addresses being different;

a downstream node with an interface and a network address in the first domain, and an upstream node including an interface and a network address in the second domain;

said intermediate node including;

i. means for receiving a first message from said downstream node, said first message including a first message body and a first header, said first message body including at least one instruction used to control said upstream node to interact with said intermediate node, said first header including the first network address as the destination address of said first message; and

ii. means for generating a second message including a second message body and a second header, said second message body including said at least one instruction from said downstream node and said second address corresponding to said second interface, said second address being for use by said upstream node when interacting with said intermediate node in accordance with said at least one instruction, said second header including a destination address corresponding to said upstream node.

19. The system of claim 18, wherein the first and second message bodies include the first network address of said first network interface of said intermediate node.

20. The system of claim 19, wherein said second network address is included in said first message body, said step of generating said second message including incorporating said second network address from said first message body into said second message body.

21. The system of claim 18, wherein said first message body includes a blank intermediate node address field and wherein said second network address is added to said second message body by said intermediate node thereby resulting in said first and second message bodies including different intermediate node address fields.

22. A communications method for use in a communications system including a first and a second network address domains, a mobile node, and an intermediate node, said intermediate node including first and second interfaces, said first interface having a first network address routable in the first network address domain, said second interface having a second network address routable in said second network address domain said first and second network addresses being different, said system further including a downstream node with an interface and a network address in the first domain, and an upstream node including an interface and a network address in the second domain, the method comprising the steps of:

operating said intermediate node to receive a first message from said downstream node, said first message including a first message body and a first header, said first message body including at least one instruction used to control said upstream node to interact with said intermediate node, said first header including the first network address as the destination address of said first message;

operating said intermediate node to generate a second message including a second message body and a second header, said second message body including said at least one instruction from said downstream node and said second address corresponding to said second interface, said second address being for use by said upstream node when interacting with said intermediate node in accordance with said at least one instruction, said second header including a destination address corresponding to said upstream node;

sending a message from the foreign agent to the mobile node identifying an IP address of a default regional node for the purposes of regional movement detection;

sending a message from the foreign agent to the mobile node that informs the mobile node of the allocation of a regional node that is not the default node, and

sending a regional registration message to the assigned regional node only whilst the default regional node received from the foreign agent is unchanged.