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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.
Roaming
A LAN mobile user moves around an ESS and enjoys a continuous connection to
an Infrastructure network.
RTS
Request To Send. 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.
