User's Manual

cially useful in education and other environments where users change fre-

quently. Using very short leases, DHCP can dynamically reconfigure networks

in which there are more computers than there are available IP addresses.

DHCP supports static addresses for computers containing Web servers that

need a permanent IP address.

DMZ (Demilitarized Zone) - Allows one IP address (or computer) to be

exposed to the Internet. Some applications require multiple TCP/IP ports to be

open. It is recommended that you set your computer with a static IP address if

you want to use DMZ Hosting.

DNS - The domain name system (DNS) is the way that Internet domain name

are located and translated into Internet Protocol (IP) addresses. A domain name

is a meaningful and easy-to-remember "handle" for an Internet address.

Domain - A subnetwork comprised of a group of clients and servers under the

control of one security database. Dividing LANs into domains improves per-

formance and security.

Download - To receive a file transmitted over a network. In a communications

session, download means receive, upload means transmit.

DSL (Digital Subscriber Line) - A technology that dramatically increases the

digital capacity of ordinary telephone lines into the home or office and, by

employing unused bandwidth, still allows for normal phone usage. DSL pro-

vides "always-on" operation, eliminating the need to dial in to the service.

DSSS (Direct-Sequence Spread Spectrum) - DSSS generates a redundant bit

pattern for all data transmitted. This bit pattern is called a chip (or chipping

code). Even if one or more bits in the chip are damaged during transmission,

statistical techniques embedded in the receiver 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. However, to an intended receiver (i.e. another wireless LAN end-

point), the DSSS signal is recognized as the only valid signal, and interference

is inherently rejected (ignored).

DTIM (Delivery Traffic Indication Message) - A DTIM field is a countdown

field informing clients of the next window for listening to broadcast and mul-

ticast messages. When the AP has buffered broadcast or multicast messages for

Wireless Access Point Router with 4-Port Switch

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