Seamless Roaming

Seamless Roaming is the ability to move freely around your building or campus while remaining connected to the wireless network.

It is impossible for a 1st generation wireless system to provide seamless roaming because in a 1st generation system each access point is a “stand-alone” ie: unaware of the existence and location of the other access points within the network. This is because there is no central control of the network and the configuration is held on each individual access point. In this circumstance as a laptop moves beyond the reach of one access point and into an area covered by another (or across an area spanning multiple access points) the laptop will need to re-associate with each access point as it comes into range and then dissassociate as it moves out of range. Each time an association is made the whole security procedure needs to be fulfilled, which means the user will need to re-log in each time.

In a 2nd generation installation the configuration of the wireless network is held at a central switch, which then controls all of the access points. As a user moves across an area from one AP to another the switch is already aware of the users existence and so manages the movement across multiple access points without the need to constantly re-associate. This means that a laptop, wireless voice phone or RF tag can move easily around the building or campus without continually losing connection and having to re-log-in.