Method for performing handoff in wireless network

Abstract

A method for minimizing handoff latencies when a handoff is performed in a wireless network. An access point (AP) or base station associated to a current wireless station (STA) allows information required for a reassociation to the STA to be propagated to handoff-capable neighboring APs or base stations. When the STA moves, a neighboring AP or base station performs the reassociation to the STA on the basis of context. When a handoff procedure is performed, the time taken to receive context of a corresponding STA is reduced, such that a fast handoff can be implemented.

Description

PRIORITY [0001] This application is a Continuation of U.S. patent application Ser. No. 10 / 703,516, which claims priority to a provisional application entitled “A METHOD FOR FAST AND SECURE WIRELESS LOCAL AREA NETWORK HANDOFFS”, filed in the United States Patent and Trademark Office on Nov. 8, 2002 and assigned Ser. No. 60 / 425,109, the contents of which are hereby incorporated by reference.GOVERNMENT RIGHTS [0002] This invention was made with Government support under Contract No. 60NANB1D0113 awarded by the National Institute of Standards and Technology. The U.S. Government has certain rights in the invention.BACKGROUND OF THE INVENTION [0003] 1. Field of the Invention [0004] The present invention relates to a method for performing a handoff in a fast and secure wireless network, and more particularly to a method for minimizing handoff latencies. [0005] 2. Description of the Related Art [0006] Conventionally, a local area network (LAN) is a collection of personal terminals, main fram...

AI Technical Summary

Benefits of technology

[0023] Accordingly, it is an aspect of the present invention to provide a method for minimizing handoff latencies.

[0025] It is yet another aspect of the present invention to provide a handoff method capable of eliminating a tunneling procedure between a prior-access point (AP) and a post-AP and a procedure of transferring state information of a corresponding wireless station (STA) through the tunneling procedure.

Problems solved by technology

Looking at it another way, handoff latency would be strictly greater than association latency as there is an additional inter-access point communication delay involved.

Some wireless network interface cards (NICs) try to initiate a reassociation prior to the authentication, which causes an additional delay in the handoff process.

Where the IAPP procedure between a new AP and other APs is additionally required, the reassociation delay will further increase.

Apart from the latencies discussed above, there will potentially be a bridging delay caused by the time taken for the MAC address updates to Ethernet switches which form the distribution system (i.e., the backbone Ethernet).

There are problems in that the latencies not only affect the quality of service (QoS) but also disable high-speed roaming.

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