Method and system for seamless roaming between wireless communication networks with a mobile terminal

• US 6,243,581 B1
• Filed: 12/11/1998
• Issued: 06/05/2001
• Est. Priority Date: 12/11/1998
• Status: Expired due to Fees

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Jawanda, Jastinder
• Primary Examiner(s): LEGREE, TRACY MICHELLE
• Application Number:
  US09/209,581
• Time in Patent Office: 907 Days
• Field of Search: 455/466, 455/426, 455/432, 455/436, 455/442, 455/550, 455/556, 455/557, 455/437, 455/440, 455/11.1, 370/315, 370/323, 370/331, 370/332, 370/338, 370/349, 370/401, 370/913
• US Class Current: 455/432.2
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/144 over a different radio air interface technology
• CPC Class Codes: H04W 36/26 by agreed or negotiated communication parameters
• CPC Class Codes: H04W 48/17 Selecting a data network PoA [Point of Attachment]
• 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]
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/16 Gateway arrangements
• CPC Class Codes: Y10S 370/913 Wireless or radio

Abstract

A mobile computer system capable of seamless roaming between wireless communication networks includes data processing resources for executing software, a plurality of wireless interfaces that supports simultaneous wireless connections with first and second wireless communication networks, and a network access arbitrator that routes data communicated between the software executed by the data processing resources and the first and second wireless communication networks. To permit seamless roaming, the network access arbitrator routes the data to the first wireless communication network via a first wireless interface and then seamlessly reroutes the data to a second wireless communication network via a second wireless interface. According to one embodiment, the network access arbitrator reroutes the data in response to the data bandwidths of the connections with the first and second wireless communication networks.

Claims

1. A mobile computer terminal, comprising:

data processing resources for executing software;

a first wireless interface directly coupled to the data processing resources that interfaces the mobile computer terminal to a cellular wireless communication network;

a second wireless interface directly coupled to the data processing resources that interfaces the mobile computer terminal to a wireless local area network;

a network access arbitrator that routes data communicated between said software executed by said data processing resources and the cellular wireless communication network via the first wireless interface; and

wherein the network access arbitrator seamlessly hand-off said data from said cellular wireless communication network via the first wireless interface to the wireless local area network via the second wireless interface in response to said mobile computer terminal having a higher bandwidth connection to the wireless local area network than to the cellular wireless network.

2. The mobile computer terminal of claim 1, wherein:

the network access arbitrator interfaces with the first wireless interface to setup a communication with the cellular wireless communication network;

the network access arbitrator interfaces with the second wireless interface to setup a communication with the wireless local area network; and

wherein the setup of the communication with the cellular wireless communication network is distinct and separate from the setup of the communication with the wireless local area network.

3. The mobile computer terminal of claim 1, and further comprising data storage that stores said software.

4. The mobile computer terminal of claim 1, wherein the first wireless interface includes a mobile telephone in data communication with the cellular wireless communication network.

5. The mobile computer terminal of claim 1, wherein:

the first wireless interface comprises a cellular telephone coupled to an input/output adapter of the mobile computer terminal; and

the second wireless interface comprises a wireless network adapter coupled to a local bus of the mobile computer terminal.

6. A method of wireless data communication within a mobile computer terminal, said method comprising:

establishing a wireless connection with a cellular wireless communication network via a first wireless interface directly coupled to the mobile computer terminal;

establishing a wireless connection with a wireless local area network via a second wireless interface directly coupled to the mobile computer terminal, the wireless connection with the local area network enabled concurrently with the wireless connection with the cellular wireless communication network;

routing data between the mobile computer system and the cellular wireless communication network via the first wireless interface; and

seamlessly handing-off data from the cellular wireless communication network via the first wireless interface to the wireless local area network via the second wireless interface in response to said mobile computer terminal having a higher bandwidth connection to the wireless local area network than to the cellular wireless network.

7. The method of claim 6, wherein the setup of the wireless connection with the cellular wireless communication network is distinct and separate from the setup of the wireless connection with the wireless local area network.

8. The method of claim 6, and further comprising executing software within said mobile computer terminal that communicates with both the cellular wireless communication network and the wireless local area network.

9. The method of claim 6, and further comprising communicating said data between said mobile computer terminal and the cellular wireless communication network utilizing a mobile telephone connected to said mobile computer terminal as the first wireless interface.

10. The method of claim 6, and further comprising communicating said data between said mobile computer terminal and the wireless local area network utilizing a wireless network adapter as the second wireless interface.

11. A computer usable medium that stores a plurality of software instructions for execution by a mobile computer terminal to support seamless roaming of a mobile computer terminal between wireless communication networks, said computer usable medium comprising:

a plurality of instructions that are executable by the mobile computer terminal to support simultaneous wireless connections between the mobile computer terminal and a cellular wireless communication network via a first wireless interface directly coupled to the mobile computer terminal and a wireless local area network via a second wireless interface directly coupled to the mobile computer terminal;

a plurality of instructions that are executable by a network access arbitrator of the mobile computer terminal to cause the network access arbitrator to route data communicated between the mobile computer terminal and the cellular wireless communication network and the wireless local area network, wherein said network access arbitrator routes said data to the cellular wireless communication network via the first wireless interface; and

wherein the network access arbitrator seamlessly hand-off said data from said cellular wireless communication network via the first wireless interface to the wireless local area network via the second wireless interface in response to said mobile computer terminal having a higher bandwidth connection to the wireless local area network than to the cellular wireless network.