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RTS
Threshold
– Transmitters contending for the medium may not hear each
other. RTS/CTS mechanism can solve this “ Hidden Node Problem”.
Spreading
– Spreading is the principal contributor to signal loss for line of sight
propagation. As a signal radiates it spreads or expands into a spherical surface.
The available RF power is distributed over this surface and weakens with
increasing range.
SSID –
An acronym for Service Set Identifier, SSID is the unique name shared
among all clients and Access Points in a wireless network. The SSID must be
identical for all clients or Access Points participating in the same network. The
SSID is case sensitive and must not exceed 30 characters.
TCP (Transmission Control Protocol) -
A protocol used along with the Internet
Protocol (IP) to send data in the form of individual units (called packets) between
computers over the Internet. While IP takes care of handling the actual delivery
of the data, TCP takes care of keeping track of the packets that a message is
divided into for efficient routing through the Internet. For example, when a web
page is downloaded from a web server, the TCP program layer in that server
divides the file into packets, numbers the packets, and then forwards them
individually to the IP program layer. Although each packet has the same
destination IP address, it may get routed differently through the network. At the
other end, TCP reassembles the individual packets and waits until they have all
arrived to forward them as a single file.
WEP (Wired Equivalent Privacy)
- WEP data encryption is defined by the
802.11 standard to prevent (i) access to the network by "intruders" using similar
wireless LAN equipment and (ii) capture of wireless LAN traffic through
eavesdropping. WEP allows the administrator to define a set of respective "Keys"
for each wireless network user based on a "Key String" passed through the WEP
encryption algorithm. Access is denied by anyone who does not have an
assigned key. The key, either 40 or 104 bits in length, is added to a 24-bit
initialization vector resulting in a 64-bit or 128-bit key size. Each station and
access point in the network must be set-up the same.
