Roaming is the ability of a portable computer user to communicatecontinuously while moving freely throughout an area greater thanthat covered by a single access point. Before using the roamingfunction, the workstation must make sure that it is the samechannel number with the Access Point of dedicated coverage area.

To achieve true seamless connectivity, the wireless LAN mustincorporate a number of different functions. Each node and accesspoint, for example, must always acknowledge receipt of eachmessage. Each node must maintain contact with the wireless networkeven when not actually transmitting data.

Achieving these functions simultaneously requires a dynamic RFnetworking technology that links access points and nodes. In such asystem, the user's end node undertakes a search for the bestpossible access to the system. First, it evaluates such factors assignal strength and quality, as well as the message load currentlybeing carried by each access point and the distance of each accesspoint the wired backbone. Based on that information the node nextselects the right access point and registers its address.

Communications between end node and host computer can then betransmitted up and down the backbone. As the user moves on, the endnodes RF transmitter regularly checks the system to determinewhether it is in touch with the original access point or whether itshould seek a new one. When a node no longer receivesacknowledgment from its original access point, it undertakes a newsearch. Upon finding a new access point, it then reregisters, andthe communication process continues.

For best results, setup your access points on differentchannels, but use the same SSID. If you are using WEP, then enterthe same key on all the access points.