Routing in a data communication network

• US 7,706,301 B2
• Filed: 10/08/2003
• Issued: 04/27/2010
• Est. Priority Date: 10/09/2002
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Petrescu, Alexandru, Lach, Hong-Yon, Janneteau, Christophe
• Primary Examiner(s): Sefcheck; Gregory B
• Assistant Examiner(s): SMITH, JOSHUA Y
• Application Number:
  US10/530,540
• Publication Number:
  US 20060050692A1
• Time in Patent Office: 2,393 Days
• Field of Search: None
• US Class Current: 370/254
• CPC Class Codes: H04L 2012/445 with switching in a hub, e.g. ETHERNET switch
• CPC Class Codes: H04L 61/5084 Providing for device mobility network addressing or numbering for mobility support in wireless networks H04W8/26; mobile IP H04W80/04
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 40/36 due to handover
• CPC Class Codes: H04W 8/02 Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 8/087 for preserving data network PoA address despite hand-offs
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A method of supporting mobility in an Internet Protocol (IP)-based data network. The method comprises the steps of generating a first stateful IP autoconfiguration message at a mobile node, whereby the message includes an address capable of use for routing maintenance. The mobile node transmits the generated message to a first access node, which incorporates its address and forwards the message to a dynamic host configuration protocol (DHCP) Server. The DHCP Server and access node analyze the message to determine a route to deliver data to and/or from the mobile node. One or more route update message are triggered from said access node and said DHCP server to a number of network elements between said access node and said DHCP server in the IP based data network to support mobility in an IP domain with minimum bandwidth use and minimum tunneling required.

Claims

1. A method of supporting mobility in an Internet Protocol version 6 (IPv6)-based data network, the method characterised by the steps of:

generating a first stateful IPv6 autoconfiguration message at a mobile node, wherein said message contains an IP address capable of use for route maintenance to and from said mobile node;

transmitting, by said mobile node, said generated message to a first access node, where said access node adds an IP address of said access node to said message;

forwarding said generated message, by said first access node, to a dynamic host configuration protocol (DHCP) Server;

analysing said message, at said DHCP server, to determine a route to deliver data one or more of to said mobile node and from said mobile node;

analysing said message, at said access node, to determine a route to deliver data one or more of to said mobile node and from said mobile node;

triggering one or more route update messages from said access node and said DHCP server to a number of network elements between said access node and said DHCP server in the IP based data network, wherein said one or more route update messages from said access node and said DHCP server are triggered substantially simultaneously;

repeating said steps of generating, transmitting and forwarding for a second stateful IP autoconfiguration message that confirms the IP address of said mobile node when said mobile node attaches to a second access node, where said second access node substitutes its address in said second message; and

in response to receiving said second stateful IP autoconfiguration message, generating one or more route update messages by said second access node and said DHCP server.

2. The method of supporting mobility according to claim 1, herein generating one or more route update messages in response to receiving said second stateful IP autoconfiguration message comprises the steps of:

analysing said second stateful IPv6 autoconfiguration message at said DHCP Server to determine that said address used for route maintenance in said second message is inconsistent with said address analysed in said first message; and

triggering a route update message based on said determination.

3. The method of supporting mobility according to claim 2, the method further characterised by the step of:

transmitting, in response to said determination, a deletion message to said first access node or said second access node and a number of network elements between said DHCP Server and said first access node or said second access node, where the deletion message instructs said number of network elements to delete obsolete address information used for route maintenance to/from said mobile node.

4. The method of supporting mobility according to claim 1, wherein one or more of said first and second stateful Internet Protocol autoconfiguration messages is a DHCPv6 ‘

CONFIRM’

message.

5. The method of supporting mobility according to claim 1, wherein said address information used for route maintenance is based on Triggered routing information protocol (RIP).

6. The method of supporting mobility according to claim 1, further characterised by the step of:

updating route maintenance information by a plurality of nodes in the IP-based data network, wherein the plurality of nodes comprises one or more of a DHCP Server, a DHCP Relay, an Access router, and an intermediate router.

13. An IPv6 communication message transmitted from a DHCP Server to an access node via a number of routers, wherein the IPv6 communication message comprises one or more of route deletion instructions and address deletion instructions generated in accordance with claim 3.

14. A non-transitory storage medium storing processor-implementable instructions to carry out the method according to claim 1.

15. An apparatus adapted to perform the method steps according to claim 1.

7. An Internet Protocol version 6(Ipv6)-based network that is operable to generate a first stateful IP autoconfiguration message at a mobile node, wherein said message contains an address capable of use for route maintenance to and from said mobile node, the network comprising hosts including one or more of a first access node, a dynamic host configuration protocol (DHCP) Relay, and a DHCP Server, the networking comprising:

a means for receiving the first stateful Ipv6 autoconfiguration message from said mobile node, wherein said message comprises a mobile node IP address capable of use for route maintenance to deliver data to, and receive data from, said mobile node, wherein said means for receiving further receives, from a second access node, a second stateful Ipv6 autoconfiguration message that confirms the IP address acquired by said mobile node prior to accessing said second access node, wherein said second access node adds its address to said second message and wherein said DHCP Server receives and analyses the second stateful IPv6 autoconfiguration message to determine whether said IP address therein is consistent with a set of addresses maintained by the DHCP Server in association with the mobile node;

a means for analyzing said first stateful IPv6 autoconfiguration message to determine a route to one or more of deliver data to, and receive data from, said mobile node; and

a means for triggering transmission of one more route update message from said first access node and said DHCP Server to a number of network elements between said first access node and a said DHCP Server in the IPv6-based data network, wherein said one or more route update messages from said first access node and said DHCP server are triggered substantially and simultaneously and wherein said means for triggering, in response to said determination of whether said IP address in the second stateful IPv6 autoconfiguration message is consistent with a set of addresses maintained by the DHCP Server in association with the mobile node, triggers one or more route update messages to one or more of said first access node and said second access node to delete obsolete address information used for route maintenance to and from said mobile node.

8. The network according to claim 7, wherein one or more of said stateful IPv6 autoconfiguration messages is an IPv6 stateful autoconfiguration ‘

CONFIRM’

message.

9. The network according to claim 7, further characterised by a memory element, operably coupled to said means for analyzing, containing a router table for storing route maintenance information extracted from said IP message.

10. The network according to claim 7, wherein one or more of said first access node and said second access node are Access Routers collocated with DHCPv6 Relay functions.

11. The network according to claim 7, wherein the network includes a number of routers located one or more of between said first access node and said DHCP Server and between said second access node and said DHCP Server in a substantially tree-type topology.

12. The network according to claim 7, wherein a communication link one or more of between said mobile node and said first access node and between said mobile node and said second access node is a wireless access media communication link to facilitate a wireless link.