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Gateway 7001 Series User Manual

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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 net mask 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.

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.

DOM

The Document Object Model (DOM) is an interface that lets programs and scripts dynamically
access and update the content, structure, and style of documents. The DOM lets you model
the objects in an HTML or XML document (text, links, images, tables), defining the
attributes of each object and how they can be manipulated.

Further details about the DOM can be found at the

W3C

.

DTIM

The

Delivery Traffic Information Map

(DTIM) message is an element included in some

Beacon frames. It indicates which stations, currently sleeping in low-power mode, have
data buffered on the

Access Point

awaiting pick-up. Part of the DTIM message indicates

how frequently stations must check for buffered data.

Dynamic IP Address

See

IP Address

.