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standards that often become national and international standards.
Infrastructure:
An infrastructure network is a wireless network type, meaning all wireless stations
communicate with each other via the Access Point.
ISM Band:
The FCC and their counterparts outside of the U.S. have set aside bandwidth for
unlicensed use in the ISM (Industrial, Scientific and Medical) band. Spectrum in the vicinity of 2.4GHz,
in particular, is being made available worldwide.
MAC Address:
Media Access Control Address is a unique hex number assigned by the manufacturer
to any Ethernet networking device, such as a network adapter, that allows the network to identify it at
the hardware level.
Multicasting:
Sending data to a group of nodes instead of a single destination.
Node:
A network junction or connection point, typically a computer or workstation.
Packet:
A unit of data routed between a source and a destination in a network.
PLCP:
Physical layer convergence protocol
PPDU:
PLCP protocol data unit
Preamble Type:
During transmission, the PSDU shall be appended to a PLCP preamble and header to
create the PPDU. Two different preambles and headers are defined as the mandatory supported long
preamble and header which interoperates with the current 1 and 2 Mbit/s DSSS specification as
described in IEEE Std 802.11-1999, and an optional short preamble and header. At the receiver, the
PLCP preamble and header are processed to aid in demodulation and delivery of the PSDU. The
optional short preamble and header is intended for application where maximum throughput is desired
and interoperability with legacy and non-short-preamble capable equipment is not consideration. That
is, it is expected to be used only in networks of like equipment that can all handle the optional mode.
(IEEE 802.11b standard)
PSDU:
PLCP service data unit
Roaming:
A LAN mobile user moves around an ESS and enjoys a continuous connection to the
distribution system.
RTS: R
equest
T
o
S
end. An RS-232 signal sent from the transmitting station to the receiving station
requesting permission to transmit.
RTS Threshold:
Transmitters contending for the medium may not be aware of each other. RTS/CTS
mechanism can solve this
“
Hidden Node Problem
”
. If the packet size is smaller than the preset RTS
Threshold size, the RTS/CTS mechanism will NOT be enabled.
SSID:
Service Set Identifier, which is a unique name shared among all clients and nodes in a wireless
network. The SSID must be identical for each clients and nodes in the wireless network.
Subnet Mask:
The method used for splitting IP networks into a series of sub-groups, or subnets. The
mask is a binary pattern that is matched up with the IP address to turn part of the host ID address field
into a field for subnets.
TCP/IP:
Transmission Control Protocol/ Internet Protocol. The basic communication language or
protocol of the Internet. It can also be used as a communications protocol in a private network, i.e.
