G
LOSSARY
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NETWORK TIME
PROTOCOL (NTP)
NTP provides the mechanisms to synchronize time across the network. The
time servers operate in a hierarchical-master-slave configuration in order
to synchronize local clocks within the subnet and to national time
standards via wire or radio.
OPEN SYSTEM A security option which broadcasts a beacon signal including the access
point’s configured SSID. Wireless clients can read the SSID from the
beacon, and automatically reset their SSID to allow immediate connection
to the nearest access point.
ORTHOGONAL
FREQUENCY DIVISION
MULTIPLEXING (ODFM)
OFDM allows multiple users to transmit in an allocated band by dividing the
bandwidth into many narrow bandwidth carriers.
SERVICE SET IDENTIFIER
(SSID)
An identifier that is attached to packets sent over the wireless LAN and
functions as a password for joining a particular radio cell; i.e., Basic Service
Set (BSS).
SESSION KEY Session keys are unique to each client, and are used to authenticate a
client connection, and correlate traffic passing between a specific client and
the access point.
SHARED KEY A shared key can be used to authenticate each client attached to a wireless
network. Shared Key authentication must be used along with the 802.11
Wireless Equivalent Privacy algorithm.
SIMPLE NETWORK TIME
PROTOCOL (SNTP)
SNTP allows a device to set its internal clock based on periodic updates
from a Network Time Protocol (NTP) server. Updates can be requested from
a specific NTP server, or can be received via broadcasts sent by NTP
servers.
TEMPORAL KEY
INTEGRITY PROTOCOL
(TKIP)
A data encryption method designed as a replacement for WEP. TKIP avoids
the problems of WEP static keys by dynamically changing data encryption
keys.
TRIVIAL FILE TRANSFER
PROTOCOL (TFTP)
A TCP/IP protocol commonly used for software downloads.
VIRTUAL ACCESS POINT
(VAP)
Virtual AP technology multiplies the number of Access Points present within
the RF footprint of a single physical access device. With Virtual AP
technology, WLAN users within the device.s footprint can associate with
what appears to be different access points and their associated network