Wireless access to packet-based networks

• US 6,654,359 B1
• Filed: 12/11/1998
• Issued: 11/25/2003
• Est. Priority Date: 12/11/1998
• Status: Expired due to Fees

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Murakami, Kazutaka, Ramjee, Ramachandran, Varadhan, Kannan, La Porta, Thomas F., Thuel, Sandra R.
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): SCHULTZ, WILLIAM C
• Application Number:
  US09/210,072
• Time in Patent Office: 1,810 Days
• Field of Search: 370/230, 370/231, 370/235.1, 370/236.2, 370/389, 370/395.1, 370/395.2, 370/400, 370/422, 370/469, 370/465, 370/401, 370/402, 370/328, 370/329, 370/330, 370/331, 455/435, 709/220, 709/221, 709/238
• US Class Current: 370/328
• CPC Class Codes: H04L 2101/604 Address structures or formats
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 61/5076 Update or notification mechanisms, e.g. DynDNS
• 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: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 40/28 for reactive routing
• CPC Class Codes: H04W 40/36 due to handover
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/005 Data network PoA devices

Abstract

Domains are defined to incorporate a subnet including a plurality of base stations and routers. Base stations are used by mobile devices to attach to the wired portion of a packet-based network, such as the Internet, and exchange packets thereover with a correspondent node. Local mobility between domain base stations is provided by including and updating routing table entries at domain routers and base stations for forwarding packets having a mobile device'"'"'s address as a destination address to the mobile device. Packets are delivered to the mobile device regardless of the domain base station to which the mobile device is attached. When a mobile device is attached to a base station included within a foreign domain, a care-of address is assigned, and packets are tunneled for delivery of packets to the mobile device. Only one care-of address is required per mobile device per foreign domain. Routing table entries used for packet delivery are updated on a purely local subnet basis within domains, whether home domain or foreign domain, making handoffs between base stations substantially transparent to the home agent and the correspondent node.

Claims

1. A method of providing wireless access to an IP packet-based network, said method comprising the steps of:

defining a first domain, said first domain including a first group of base stations;

providing a home agent for a wireless device within said first domain;

assigning a first address for delivery of a plurality of packets to said wireless device, said first address utilized when said wireless device is attached to said packet-based network through a base station included within said first domain;

receiving, at said home agent, a second address for said wireless device when said wireless device is attached to said packet-based network through a base station excluded from said first domain; and

tunneling said plurality of packets from said home agent to said second address for said wireless device if said wireless device is attached to said packet-based network through said base station excluded from said first domain,

wherein said first address continues to be utilized by said network for delivery of said plurality of packets to said wireless device when said wireless device is handed off to any base station included within said first domain.

2. The method in accordance with claim 1 wherein a plurality of packet routers are included within said first domain to interconnect said first group of base stations over a wired portion of said packet-based network.

3. The method in accordance with claim 1 further comprising the step of:

updating routing table entries of said plurality of packet routers and said first group of base stations within said first domain utilizing path setup messages.

4. The method in accordance with claim 1 wherein said first domain is a subnet using a common local protocol for signaling and messaging within said subnet.

5. The method in accordance with claim 1 wherein said first address is associated with said wireless device for as long as said wireless device is attached to a base station included within said first domain.

6. The method in accordance with claim 5 wherein routing table entries corresponding to said first address at said packet routers and said first group of base stations are updated to forward said plurality of packets to said wireless device whenever said wireless device is attached to said packet-based network through one of said first group of base stations.

7. A method of providing mobile device access to an IP packet-based network from a plurality of base stations adapted for packet routing via a plurality of routers attached to said packet-based network, said method comprising the steps of:

defining a first domain, said first domain including a first group of said plurality of base stations interfaced with said packet-based network via a first group of said plurality of routers;

assigning a first address for delivery of a plurality of packets to a mobile device, said first address corresponding to said mobile device and utilized whenever said mobile device is attached to said packet-based network through one of said first group of said plurality of base stations; and

updating a routing table entry corresponding to said first address in selected ones of said first group of said plurality of routers and said first group of said plurality of base stations to specify a routing path through said first group of said plurality of routers and said first group of said plurality of base stations for delivery of said plurality of packets to said mobile device, regardless of the one of said first plurality of base stations through which said mobile device is attached to said packet-based network, wherein said first address continues to be utilized by said network for delivery of said plurality of packets to said wireless device when said wireless device is handed off to any base station included within said first domain.

8. The method in accordance with claim 7 further comprising the steps of:

designating a router, from said first group of said plurality of routers, as a root router;

defining a second domain, said second domain including a second group of said plurality of base stations interfaced with said packet-based network via a second group of said plurality of routers;

assigning a second address for delivery of said plurality of packets to said mobile device;

conveying said second address to said root router; and

tunneling said plurality of packets from said root router, through at least one selected router from said second group of said plurality of routers, through one of said second group of said plurality of base stations, and to said mobile device, when said mobile device is attached to said packet-based network through said one of said second group of said plurality of base stations.

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

updating a routing table entry corresponding to said second address in selected ones of said second group of said plurality of routers and said second group of said plurality of base stations to establish a routing path associated with said step of tunneling.

10. The method in accordance with claim 9 wherein said step of updating is accomplished through the conveyance of at least one path setup message.

11. The method in accordance with claim 9 wherein said packet-based network is an Internet Protocol network.

12. The method in accordance with claim 11 wherein said first domain is a service provider subnet utilizing a common local protocol for signaling and messaging within said service provider subnet.

13. The method in accordance with claim 11 wherein said second domain is a service provider subnet utilizing a common local protocol for signaling and messaging within said service provider subnet.

14. A method of providing wireless access to an IP packet-based network, said method comprising the steps of:

defining a domain, said domain including a plurality of base stations interconnected with a plurality of routers to provide said wireless access to said packet-based network for a wireless device;

assigning a domain-based address to said wireless device;

messaging selected ones of said plurality of base stations and selected ones of said plurality of routers to update a routing table entry to reflect said wireless device'"'"'s present point of attachment to a single one of said base stations;

receiving, at one of said plurality of routers, a packet having said domain-based address as a packet destination address;

routing said packet over a router interface determined by look-up of said domain-based address corresponding to said routing table entry; and

repeating said steps of receiving and routing until said packet is received at said wireless device, wherein said domain-based address continues to be utilized by said network for delivery of said plurality of packets to said wireless device when said wireless device is handed off to any base station included within said domain.