Uniden WNP1000 - Manual (Page 25)

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Cable Modem – A device that connects a computer to the cable television
network, which in turn connects to the Internet. Once connected, cable modem
users have a continuous connection to the Internet. Cable modems feature
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).
Data Packet - One frame in a packet-switched message. Most data
communication is based on dividing the transmitted message into packets.
For example, an Ethernet packet can be from 64 to 1518 bytes in length.
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 centrally manage and automate the assignment of Internet
Protocol (IP) addresses in an organization’s network. Using the Internet’s set of
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
connection 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 distribute 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 especially useful in education and other environments where users change
frequently. 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.
DNS - The Domain Name System (DNS) is the way that Internet domain names
are located and translated into an Internet Protocol (IP) address. A domain
name is a meaningful and easy-to-remember “handle” for an Internet address.
Domain - A sub network comprised of a group of clients and servers under the
control of one security database. Dividing LANs into domains improves
performance and security.
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Download - To receive a file transmitted over a network. In a communications
session, download means receive, and upload means transmit.
Driver - A software module that provides an interface between a network
interface card and the upper-layer protocol software running in the computer; it
is designed for a specific adapter, and is installed during the setup of the
adapter.
DSSS (Direct-Sequence Spread-Spectrum) - DSSS generates a redundant bit
pattern for each bit 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.
Dynamic IP Address - An IP address that is automatically assigned to a client
station in a TCP/IP network, typically by a DHCP server. Network devices that
serve multiple users, such as servers and printers, are usually assigned static
IP addresses.
Dynamic Routing - The ability for a router to forward data via a different route
based on the current conditions of the communications circuits. For example, it
can adjust for overloaded traffic or failing lines and is much more flexible than
static routing, which uses a fixed forwarding path.
Ethernet - IEEE standard network protocol that specifies how data is placed on
and retrieved from a common transmission medium. Has a transfer rate of 10
Mbps. Forms the underlying transport vehicle used by several upper-level
protocols, including TCP/IP and XNS.
Fast Ethernet - A 100 Mbps technology based on the 10Base-T Ethernet
CSMA/CD network access method.
Firewall – A firewall is a set of related programs, located at a network gateway
server, which protects the resources of a network from users from other
networks. (The term also implies the security policy that is used with the
programs.) An enterprise with an intranet that allows its workers access to the
wider Internet installs a firewall to prevent outsiders from accessing its own
private data resources and for controlling what outside resources to which its
own users have access. A firewall, working closely with a router, examines