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DSSS:
Direct Sequence Spread Spectrum. DSSS generates a redundant bit
pattern for each bit to be transmitted. This bit pattern is called a chip (or chipping
code). The longer the chip, the greater the probability that the original data can
be recovered. Even if one or more bits in the chip are damaged during
transmission, statistical techniques embedded in the radio can recover the
original data without the need for retransmission. To an unintended receiver,
DSSS appears as low power wideband noise and is rejected (ignored) by most
narrowband receivers.
Dynamic IP Address:
An IP address that is assigned automatically to a client
station in a TCP/IP network by a DHCP server.
Encryption:
A security method that uses a specific algorithm to alter the data
transmitted, thus prevent others from knowing the information transmitted.
ESS:
ESS stands for “Extended Service Set”. More than one BSS is configured
to become Extended Service Set. LAN mobile users can roam between different
BSSs in an ESS.
ESSID:
The unique identifier that identifies the ESS. In infrastructure association,
the stations use the same ESSID as AP’s to get connected.
Ethernet:
A popular local area data communications network, originally
developed by Xerox Corp., that accepts transmission from computers and
terminals. Ethernet operates on a 10/100 Mbps base transmission rate, using
a shielded coaxial cable or over shielded twisted pair telephone wire.
Fragmentation:
When transmitting a packet over a network medium,
sometimes the packet is broken into several segments, if the size of packet
exceeds that allowed by the network medium.
Fragmentation Threshold:
The Fragmentation Threshold defines the number
of bytes used for the fragmentation boundary for directed messages. The
purpose of "Fragmentation Threshold" is to increase the transfer reliability thru
cutting a MAC Service Data Unit (MSDU) into several MAC Protocol Data Units
(MPDU) in smaller size. The RF transmission can not allow to transmit too big
frame size due to the heavy interference caused by the big size of transmission
frame. But if the frame size is too small, it will create the overhead during the
transmission.
