Field Guide to Wireless LANs for Administrators and Power Users, A

Components of IEEE 802.11 LANs

An IEEE 802.11 LAN Basic Service Set (BSS) can operate in one of exactly two modes, specifically “independent” or “infrastructure.” A BSS in infrastructure mode is also sometimes referred to as being part of an ESS (Extended Service Set; a collection of more than one BSS and the necessary wired LAN Distribution System (DS) that ties them together), which behaves logically like an extended BSS. To make a collection of BSS WLANs into an ESS, they must all identify themselves using the same Service Set Identifier (SSID, or ESSID, or BSSID, depending on the context, but in any case it's the same thing, a string of up to 32 characters that identifies each BSS.^[11]

^[11] For example, the author's home WLAN's SSID is “police ...