System and method for concurrent operation of a wireless device in two disjoint wireless networks

• US 20030054818A1
• Filed: 09/17/2001
• Published: 03/20/2003
• Est. Priority Date: 09/17/2001
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bahl, Paramvir, Bahl, Pradeep
• Granted Patent: US 7,194,263 B2
• Time in Patent Office: Days
• US Class Current: 455/432.1
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 74/06 using polling
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor 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

Abstract

A system and method for wireless network communications provides a “dual-mode” wireless device that operates concurrently as a member of two disjoint wireless networks, such as an infrastructure (“IS”) network and an ad hoc (“AH”) network. The dual-mode device has a wireless controller driver inserted in its networking stack (e.g., the stack comprising of the Network and NDIS drivers) that exposes two virtual wireless network adapters, one for the first wireless network and one for the second wireless network. Each virtual wireless network adapter has an associated queue for queuing packets in the flow for the corresponding wireless network mode. The wireless controller driver controls the switching of the network mode. In one embodiment where the two networks include an IS network and an AH network, the mode switching is triggered by poll signals transmitted by an access point of the IS network. When the mode is switched from operating in the first network to operating in the second network, the first virtual network adapter is disabled and the second virtual network adapter is enabled, and the queued packets in the queue for the second virtual network adapter are transmitted over the second wireless network.

Claims

1. A computer readable medium having computer-executable instructions for performing steps for a wireless device to participate in first and second wireless networks that are disjoint and having overlapping transmission ranges over a common frequency channel, comprising:

exposing a first virtual network adapter associated with a first operation mode for communicating with the first wireless network and a second virtual network adapter associated with a second operation mode for communicating with the second wireless network;

providing a first queue for queuing packets for communications in the first operation mode and a second queue for queuing packets for communications in the second operation mode;

in response to a first instruction to switch to the first operation mode, enabling the first virtual network adapter and transmitting queued packets in the first queue to the first wireless network; and

in response to a second instruction to switch to the second operation mode, enabling the second virtual network adapter and transmitting queued packets in the second queue to the second wireless network.

2. A computer-readable medium as in claim 1, wherein the common frequency channel is a radio frequency channel.

3. A computer-readable medium as in claim 1, wherein the first wireless network is an infrastructure network and the second wireless network is an ad hoc network.

4. A computer-readable medium as in claim 3, wherein the first and second instructions are first and second poll signals, respectively, transmitted by an access point of the infrastructure network.

5. A computer-readable medium as in claim 4, having further computer-executable instructions for performing the step of registering the wireless device with the access point as an ad hoc node or a dual-mode node.

6. A computer-readable medium as in claim 4, having further computer-executable instructions for performing the step of determining from a wireless mode specified in the first poll signal that the first poll signal is an instruction for switching to the first operation mode and determining from a wireless mode specified in the second poll signal that the second poll signal is an instruction for switching to the second operation mode.

7. A computer network system comprising:

an infrastructure wireless network having an access point and transmitting over a frequency channel;

an ad hoc wireless network within a range of the infrastructure wireless network and transmitting over the same frequency channel; and

a wireless device concurrently participating in the infrastructure wireless network and the ad hoc wireless network, the wireless device being programmed to switch between an infrastructure operation mode for communicating with nodes in the infrastructure network though the access point and to an ad hoc operation mode for communicating with nodes in the ad hoc wireless network.

8. A computer network system as in claim 7, wherein the frequency channel is a radio frequency channel.

9. A computer network system as in claim 7, wherein the access point transmits poll signals for coordinating bandwidth usage of the frequency channel used by the infrastructure and ad hoc networks for wireless transmissions, and wherein the wireless device switches to the infrastructure operation mode in response to a poll signal of a first kind from the access point and switches to the ad hoc operation mode in response to a poll signal of a second kind from the access point.

10. A computer network system as in claim 7, wherein the wireless device has a device stack having exposed therein a first virtual network adapter enabled for the infrastructure operation mode and a second virtual network adapter enabled for the ad hoc operation mode, whereby the switching is transparent to at least the networking layer of an operating system of the wireless device.

11. A computer network system as in claim 10, wherein the wireless device further includes a first queue for queuing communication packets for transmission in the infrastructure operation mode and a second queue for queuing communication packets for transmission in the ad hoc operation mode.

12. A computer network system as in claim 9, wherein the access point unicasts the poll signal of the first kind to a node in the infrastructure network and broadcasts the poll signal of the second kind to nodes in the ad hoc network.