G
LOSSARY
683
FDB
See
forwarding database (FDB)
.
Federal
Communications
Commission
See
FCC
.
FHSS
Frequency-hopping spread-spectrum. One of two types of
spread-spectrum radio technology used in wireless LAN (WLAN)
transmissions. The FHSS technique modulates the data signal with a
narrowband carrier signal that “hops” in a predictable sequence from
frequency to frequency as a function of time over a wide band of
frequencies. Interference is reduced, because a narrowband interferer
affects the spread-spectrum signal only if both are transmitting at the
same frequency at the same time. The transmission frequencies are
determined by a spreading (
hopping
) code. The receiver must be set to
the same hopping code and must listen to the incoming signal at the
proper time and frequency to receive the signal. Compare
DSSS
.
forwarding database
(FDB)
A database maintained on a Wireless Switch (WX) for the purpose of
making Layer 2 forwarding and filtering decisions. Each entry consists
of the media access control (MAC) address of a source or destination
device, an identifier for the port on which the source or destination
station is located, and an identifier for the virtual LAN (VLAN) to which
the device belongs. FDB entries are either permanent (never deleted),
static (not aged, but deleted when the WX is restarted or loses power),
or dynamic (learned dynamically and removed through aging or when
the WX is restarted or loses power).
frequency-hopping
spread-spectrum
See
FHSS
.
GBIC
Gigabit interface converter. A hot-swappable input/output device that
plugs into a gigabit Ethernet port, to link the port with a fiber-optic or
copper network. The data transfer rate is 1 gigabit per second (Gbps)
or more. Typically employed as high-speed interfaces, GBICs allow you
to easily configure and upgrade communications networks.
gigabit interface
converter
See
GBIC
.
glob
See
MAC address glob
;
user glob
;
VLAN glob
.
Summary of Contents for 3CRWX120695A
Page 138: ...138 CHAPTER 6 CONFIGURING AND MANAGING IP INTERFACES AND SERVICES ...
Page 272: ...272 CHAPTER 11 CONFIGURING RF LOAD BALANCING FOR MAPS ...
Page 310: ...310 CHAPTER 13 CONFIGURING USER ENCRYPTION ...
Page 322: ...322 CHAPTER 14 CONFIGURING RF AUTO TUNING ...
Page 350: ...350 CHAPTER 16 CONFIGURING QUALITY OF SERVICE ...
Page 368: ...368 CHAPTER 17 CONFIGURING AND MANAGING SPANNING TREE PROTOCOL ...
Page 412: ...412 CHAPTER 19 CONFIGURING AND MANAGING SECURITY ACLS ...
Page 518: ...518 CHAPTER 21 CONFIGURING AAA FOR NETWORK USERS ...
Page 530: ...530 CHAPTER 22 CONFIGURING COMMUNICATION WITH RADIUS ...
Page 542: ...542 CHAPTER 23 MANAGING 802 1X ON THE WX SWITCH ...
Page 598: ...598 CHAPTER 26 ROGUE DETECTION AND COUNTERMEASURES ...
Page 706: ...706 GLOSSARY ...