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Apendix B: Glossary
Corinex Wireless to Powerline AP
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 and automate the assignment of Internet
Protocol (IP) addresses centrally in an company network. Using the Internet
set of protocols (TCP/IP), each machine that can connect to the Internet
needs a unique IP address. When an organization enables to its computer
users an Internet connection, 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 to 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 is especially useful in
education and other environments where the alternation of users is more
frequent. Using very short leases, DHCP can dynamically reconfigure
networks in which operate more computers than available IP addresses.
DHCP supports static addresses for computers containing Web servers that
need a permanent IP address.
DNS
(Domain Name System)
- A distributed name/address mechanism
used in the Internet.
Domain
- A subnetwork comprised of a group of clients and servers under
the control of one security database. Dividing LANs into domains improves
its performance and security.
Download
- To receive a file transmitted over a network. In a communications
session, download means receive, and upload means transmit.
DSSS (Direct-Sequence Spread-Spectrum)
- DSSS generates a redundant
bit pattern for each bit to be transmitted. This bit pattern is called a chip
(or chipping code). The longer the chip, the greater is 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 any need for retransmission.
DSSS appears as low power wideband noise to an unintended receiver and
is rejected (ignored) by most narrowband receivers.