Copyright © 2004-2005, Vivato, Inc.
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AES
The
Advanced Encryption Standard
(AES) is a symmetric 128-bit block data encryption technique
developed to replace DES encryption. AES works at multiple network layers simultaneously.
Further information is available on the
.
Basic Rate Set
The
basic rate set
defines the transmission rates that are mandatory for any station wanting to join this
wireless network. All stations must be able to receive data at the rates listed in this set.
Beacon
Beacon frames
provide the "heartbeat" of a
, announcing the existence of the network, and enabling
stations to establish and maintain communications in an orderly fashion. It carries the following information
(some of which is optional):
•
The
Timestamp
is used by stations to update their local clock, enabling synchronization among all
associated stations.
•
The
Beacon interval
defines the amount of time between transmitting beacon frames. Before entering
power save mode, a station needs the beacon interval to know when to wake up to receive the bea-
con.
•
The
Capability Information
lists requirements of stations that want to join the
. For example, it
indicates that all stations must use
•
The
Service Set Identifier
•
The
is a bitmap that lists the rates that the
supports.
•
The optional
Parameter Sets
indicates features of the specific signaling methods in use (such as fre-
quency hopping spread spectrum, direct sequence spread spectrum, etc.).
•
The optional
Traffic Indication Map
(TIM) identifies stations, using power saving mode, that have data
frames queued for them.
Bridge
A connection between two local area networks (
s) using the same protocol, such as Ethernet or
Broadcast
A
Broadcast
sends the same message at the same time to everyone. In wireless networks, broadcast
usually refers to an interaction in which the AP/Bridge sends data traffic in the form of
to all client stations on the network.
Some wireless security modes distinguish between how unicast, multicast, and broadcast frames are
encrypted or whether they are encrypted.
See also
and