LevelOne WNC-0200, Руководство пользователя

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area, the AP address, the Broadcast destination addresses, time stamp, Delivery
Traffic Indicator Maps, and the Traffic Indicator Message (TIM).
Bit ? A binary digit, which is either -0 or -1 for value, is the smallest unit for data.
Bridge ? An internetworking function that incorporates the lowest 2 layers of the
OSI network protocol model.
Browser ? An application program that enables one to read the content and interact
in the World Wide Web or Intranet.
BSS ? BSS stands for “Basic Service Set”. It is an Access Point and all the LAN
PCs that associated with it.
Channel ? The bandwidth which wireless Radio operates is divided into several
segments, which we call them “Channels”. AP and the client stations that it
associated work in one of the channels.
CSMA/CA ? In local area networking, this is the CSMA technique that combines
slotted time -division multiplexing with carrier sense multiple access/collision
detection (CSMA/CD) to avoid having collisions occur a second time. This works
best if the time allocated is short compared to packet length and if the number of
situations is small.
CSMA/CD ? Carrier Sense Multiple Access/Collision Detection, which is a LAN
access method used in Ethernet. When a device wants to gain access to the network,
it checks to see if the network is quiet (senses the carrier). If it is not, it waits a
random amount of time before retrying. If the network is quiet and two devices
access the line at exactly the same time, their signals collide. When the collision is
detected, they both back off and wait a random amount of time before retrying.
DHCP
? Dynamic Host Configuration Protocol, which is a protocol that lets
network administrators manage and allocate Internet Protocol (IP) addresses in a
network. Every computer has to have an IP address in order to communicate with
each other in a TCP/IP based infrastructure network. Without DHCP, each computer
must be entered in manually the IP address. DHCP enables the network
administrators to assign the IP from a central location and each computer receives an
IP address upon plugged with the Ethernet cable everywhere on the network.
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.