D-Link DWL-2200AP [170/192] Csma ca

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Glossary
CSMA/CA
Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is a low-level network
arbitration/contention protocol. A station listens to the media and attempts to transmit a
packet when the channel is quiet. When it detects that the channel is idle, the station transmits
the packet. If it detects that the channel is busy, the station waits a random amount of time
and then attempts to access the media again.
CSMA/CA is the basis of the IEEE 802.11e Distributed Control Function (DCF). See also RTS
and CTS.
The CSMA/CA protocol used by 802.11 networks is a variation on CSMA/CD (used by Ethernet
networks). In CSMA/CD the emphasis is on collision detection whereas with CSMA/CA the
emphasis is on collision avoidance.
CTS
A clear to send (CTS) message is a signal sent by an IEEE 802.11 client station in response
to a request to send (RTS) message. The CTS message indicates that the channel is clear
for the sender of the RTS message to begin data transfer. The other stations will wait to keep
the air waves clear. This message is a part of the IEEE 802.11 CSMA/CA protocol. (See also
RTS.)
DCF
The Distribution Control Function is a component of the IEEE 802.11e Quality of Service
(QoS) technology standard. The DCF coordinates channel access among multiple stations
on a wireless network by controlling wait times for channel access. Wait times are determined
by a random backoff timer which is configurable by defining minimum and maximum contention
windows.
DHCP
The Dynamic Host Configuration Protocol (DHCP) is a protocol specifying how a central
server can dynamically provide network configuration information to clients. A DHCP server
“offers” a “lease” (for a pre-configured period of time—see Lease Time) to the client system.
The information supplied includes the client’s IP addresses and netmask plus the address
of its DNS servers and Gateway.
DNS
The Domain Name Service (DNS) is a general-purpose query service used for translating
fully-qualified names into Internet addresses. A fully-qualified name consists of the hostname
of a system plus its domain name. For example, www is the host name of a Web server and
www.dlink.com is the fully-qualified name of that server. DNS translates the domain name
www.dlink.com to some IP address, for example 66.93.138.219.
A domain name identifies one or more IP addresses. Conversely, an IP address may map to
more than one domain name.
A domain name has a suffix that indicates which top level domain (TLD) it belongs to. Every
country has its own top-level domain, for example .de for Germany, .fr for France, .jp
for Japan, .tw for Taiwan, .uk for the United Kingdom, .us for the U.S.A., and so on.
There are also .com for commercial bodies, .edu for educational institutions, .net for
network operators, and .org for other organizations as well as .gov for the U. S. government
and .mil for its armed services.

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