InstantWave
11-Mbps USB Wireless LAN Adapter
3
BSSID, MAC Address
A Basic Service Set (BSS) is two or more wireless devices that are in
communication with each other. Like every wired Ethernet device, every wireless
device has a fixed, unique “media access control” (MAC) address. When wireless
devices establish communication, they automatically select the MAC address of
one BSS member as an identifier for the group; this is the BSSID.
It has become customary to refer to a wireless device’s MAC address as its BSSID
even when the address is not being used to identify an active BSS.
A BSS that includes an access point is often referred to as a
cell
.
SSID, Domain Identifier
A Service Set Identifier (SSID) is a shared name, usually assigned by a network
administrator, that identifies wireless devices that are allowed to communicate with
each other. This is one way of providing basic security on a wireless network. An
SSID can be up to 32 characters long, and can include letters and numbers.
Giving multiple access points the same SSID and encryption settings allows
mobile stations that also share those settings to “roam” from one AP to another.
When at least one AP is among the devices sharing an SSID, the name may be
referred to as an
Extended Service Set Identifier
(ESSID).
An SSID is sometimes called a “domain name,” but it is unrelated to the domain
names used to identify machines and networks on the Internet. Other terms for
SSID are
domain ID
,
net ID
,
network name
,
extended network ID
, and
wireless
network name
. The set of devices that an SSID identifies is sometimes called a
communication domain
or
wireless domain
.
Figure 3 shows a common wireless network setup. If the APs share SSID and
encryption settings, mobile devices that also share those settings can roam among
them.
Figure 3. Roamable multi-AP infrastructure network
