Patent ID: 7904086
Filing Date: 2011-03-08
Classification: H04W

Abstract:
1. A method for managing handoff of a mobile device between wireless access points, the method comprising: during a networking initialization phase for a mobile device, scanning channels from the mobile device to detect wireless access points, building a candidate list in the mobile device, wherein the candidate list contains entries representing candidate wireless access points from among the detected access points, reserving Internet protocol (IP) addresses for the mobile device on the access points in the candidate list, and establishing a communication connection between the mobile device and a first access point among the access points in the candidate list via a first IP address among the reserved IP addresses, wherein the first access point belongs to a first sub-network and a first channel; after the networking initialization phase, switching the mobile device to a normal processing mode; periodically switching the mobile device from the normal processing mode to a background monitoring phase; during the background monitoring phase, performing monitoring operations by the mobile device, the monitoring operations comprising: determining whether any access points should be removed from the candidate list, based on the signal strength detected in the background monitoring phase; in response to a determination that one or more access points should be removed from the candidate list, removing said one or more access points from the candidate list; determining whether an additional access point should be added to the candidate list, based on a threshold number of access points; in response to a determination that an additional access point should be added to the candidate list, performing candidate list replenishment operations comprising: outside of the background monitoring phase, upon detection of a predetermined threshold of signal strength associated with a need to handoff from the first access point, selecting a second access point from the candidate list, and transferring communication to the second access point in association with a second IP address that was reserved on the second access point for the mobile device before the mobile device detected the need to handoff from the first access point.