User's Manual

Back to Contents

Glossary

Numerical A B D E F I K M O P R S T U W

Numerical

802.11 x: A series of IEEE specifications for LANs: currently 802.11b, 802.11a, and 802.11g. Using any one of

these extensions to the 802.11 standard permits wireless communication between a client and an access point

or between two clients. The various specifications govern transmission speeds and radio frequencies as well as

fall-back rates and other characteristics. The upcoming standard 802.11i will provide additional security specific

to WLANs, and 802.11e will address quality of service.

Access Point: A device that serves as a communications hub for wireless clients and provides a connection to

a wired LAN.

Advanced Encryption Standard (AES): A federal information-processing standard, supporting 128-, 192-,

and 256-bit keys.

Basic Service Set Identifier (BSSID): A unique identifier for each wireless client on a wireless network. The

BSSID is the Ethernet MAC address of each adapter on the network.

Bit Rate: The total number of bits (ones and zeros) per second that a network connection can support. Note

that this bit rate will vary, under software control, with different signal path conditions.

Bluetooth: An incompatible, very short-range lower speed communications system (PAN), developed first in

Europe as a “cable replacement” for printers and similar peripheral connections. Its usage has expanded to

include cordless earphones and similar devices. It uses the 2.4 GHz ISM band, and “co-exists” with 802.11b.

Here the term, “co-exist” means that not all researchers agree on the amount of mutual interference generated

when both systems operate in the same location.

Broadcast SSID: Used to allow an access point to respond to clients on a wireless network by sending probes.

Data Rate (Information Rate): Not all bits carry user information. Each group (packet) of bits contains

headers, trailers, echo control, destination information, and other data required by the transmission protocol. It

is important to understand the difference between bit rate and data rate, since the overhead information may

consume more than 40% of the total transmission. This difference is common to many such data systems,

including Ethernet.