Linksys BEFW11S4 - Manual (Page 48)

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associated clients, it sends the next DTIM with a DTIM Interval value. AP
Clients hear the beacons and awaken to receive the broadcast and multicast
messages.
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.
Encryption - A security method that applies a specific algorithm to data in
order to alter the data's appearance and prevent other devices from reading the
information.
ESS (Extended Service Set) - A set of more than two or more BSSs (multiple
access points) forming a single network.
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.
FHSS (Frequency Hopping Spread Spectrum) - FHSS continuously changes
(hops) the carrier frequency of a conventional carrier several times per second
according to a pseudo-random set of channels. Because a fixed frequency is not
used, and only the transmitter and receiver know the hop patterns, interception
of FHSS is extremely difficult.
Finger - A UNIX command widely used on the Internet to find out informa-
tion about a particular user, such as telephone number, whether currently
logged on or the last time logged on. The person being "fingered" must have
placed his or her profile on the system. Fingering requires entering the full
user@domain address.
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
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