RF-Link WRT55AG - Manual (Page 54)

Dual-Band Wireless A+G Broadband Router
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asymmetric transfer rates: around 36 Mbps downstream (from the Internet to
the computer), and from 200 Kbps to 2 Mbps upstream (from the computer to
the Internet).
CAT 5 - ANSI/EIA (American National Standards Institute/Electronic
Industries Association) Standard 568 is one of several standards that specify
"categories" (the singular is commonly referred to as "CAT") of twisted pair
cabling systems (wires, junctions, and connectors) in terms of the data rates
that they can sustain. CAT 5 cable has a maximum throughput of 100 Mbps and
is usually utilized for 100BaseTX networks.
Cookie - Data created by a Web server that is stored on a user's computer. It
provides a way for the Web site to keep track of a user's patterns and prefer-
ences and, with the cooperation of the Web browser, to store them on the user's
own hard disk.
CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) - In local
area networking, this is the CSMA technique that combines slotted time-divi-
sion 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 sit-
uations is small.
CTS (Clear To Send) - An RS-232 signal sent from the receiving station to the
transmitting station that indicates it is ready to accept data.
Daisy Chain - Connected in series, one after the other. Transmitted signals go
to the first device, then to the second and so on.
DDNS (Dynamic Domain Name System) - Allows a network device with a
dynamic Internet IP address to have a fixed host and domain name, such as
myhostname.mydomainname.com. It is useful when you are hosting your own
website, FTP server, or other server behind a router, so people can find your
site no matter how often the Internet IP address changes. Using DDNS requires
registering with a DDNS service provider on the Internet.
Default Gateway - The routing device used to forward all traffic that is not
addressed to a station within the local subnet.
DHCP (Dynamic Host Configuration Protocol) - A protocol that lets network
administrators manage centrally and automate the assignment of Internet
Protocol (IP) addresses in an organization's network. Using the Internet's set of
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protocol (TCP/IP), each machine that can connect to the Internet needs a
unique IP address. When an organization sets up its computer users with a con-
nection to the Internet, an IP address must be assigned to each machine.
Without DHCP, the IP address must be entered manually at each computer and,
if computers move to another location in another part of the network, a new IP
address must be entered. DHCP lets a network administrator supervise and dis-
tribute IP addresses from a central point and automatically sends a new IP
address when a computer is plugged into a different place in the network.
DHCP uses the concept of a "lease" or amount of time that a given IP address
will be valid for a computer. The lease time can vary depending on how long a
user is likely to require the Internet connection at a particular location. It's espe-
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. You should 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
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