Wireless Roaming with ESSID

An ESSID (Extended Service Set IDentifier) is a collection of Access Points (or Virtual Access Points) sharing the same SSID. A typical wireless network comprises more than one AP for the purpose of covering geographic areas larger than can be serviced by a single AP. As clients move through the wireless network, the strength of their wireless connection decreases as they move away from one Access Point (AP1) and increases as they move toward another (AP2). Providing AP1 and AP2 are on the same ESSID (for example, SonicWall) and that the (V)APs share the same SSID and security configurations, the client can roam from one to the other. This roaming process is controlled by the wireless client hardware and driver, so roaming behavior can differ from one client to the next, but it is generally dependent upon the signal strength of each AP within an ESSID.