Linksys BEFSX41 Network Router User Manual


 
EtherFast
®
Cable/DSL Firewall Router with 4-Port Switch/VPN Endpoint
Hub - The device that serves as the central location for attaching wires from
workstations. Can be passive, where there is no amplification of the signals; or
active, where the hubs are used like repeaters to provide an extension of the
cable that connects to a workstation.
ICMP (Internet Control Message Protocol) - Part of the TCP/IP protocol.
Network devices such as routers or servers use ICMP to transmit error mes-
sages and control messages. For example, the PING program uses ICMP.
ICQ - A conferencing program for the Internet that provides interactive chat,
e-mail and file transfer and can alert you when someone on your predefined list
has also come online.
IEEE (The Institute of Electrical and Electronics Engineers) - The IEEE
describes itself as "the world's largest technical professional society, promoting
the development and application of electrotechnology and allied sciences for
the benefit of humanity, the advancement of the profession, and the well-being
of our members."
The IEEE fosters the development of standards that often become national and
international standards. The organization publishes a number of journals, has
many local chapters, and several large societies in special areas, such as the
IEEE Computer Society.
IKE (Internet Key Exchange) - A negotiation and key exchange protocol spec-
ified by the Internet Engineering Task Force. An IKE security association (SA)
automatically negotiates encryption and authentication keys. With IKE, an ini-
tial exchange authenticates the VPN session and automatically negotiates keys
that will be used to pass encrypted data over the Internet or any other network.
IP (Internet Protocol) - The method or protocol by which data is sent from one
computer to another on the Internet. It is a standard set of rules, procedures, or
conventions relating to the format and timing of data transmission between two
computers that they must accept and use to be able to understand each other.
IP Address - In the most widely installed level of the Internet Protocol (IP)
today, an IP address is a 32-binary digit number that identifies each sender or
receiver of information that is sent in packet across the Internet. When you
request an HTML page or send e-mail, the Internet Protocol part of TCP/IP
includes your IP address in the message (actually, in each of the packets if more
than one is required) and sends it to the IP address that is obtained by looking
up the domain name in the Uniform Resource Locator you requested or in the
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Instant Broadband
®
Series
Firmware - Code that is written onto read-only memory (ROM) or program-
mable read-only memory (PROM). Once firmware has been written onto the
ROM or PROM, it is retained even when the device is turned off.
FTP (File Transfer Protocol) - A protocol used to transfer files over a TCP/IP
network (Internet, UNIX, etc.). For example, after developing the HTML pages
for a Web site on a local machine, they are typically uploaded to the Web serv-
er using FTP.
FTP includes functions to log onto the network, list directories and copy files.
It can also convert between the ASCII and EBCDIC character codes. FTP oper-
ations can be performed by typing commands at a command prompt or via an
FTP utility running under a graphical interface such as Windows. FTP transfers
can also be initiated from within a Web browser by entering the URL preceded
with ftp://.
Unlike e-mail programs in which graphics and program files have to be
"attached," FTP is designed to handle binary files directly and does not add the
overhead of encoding and decoding the data.
Full Duplex - The ability of a device or line to transmit data simultaneously in
both directions.
Gateway - A device that interconnects networks with different, incompatible
communications protocols.
Half Duplex - Data transmission that can occur in two directions over a single
line, but only one direction at a time.
Hardware - Hardware is the physical aspect of computers, telecommunica-
tions, and other information technology devices. The term arose as a way to dis-
tinguish the "box" and the electronic circuitry and components of a computer
from the program you put in it to make it do things. The program came to be
known as the software.
Hop - The link between two network nodes.
HTTP (HyperText Transport Protocol) - The communications protocol used
to connect to servers on the World Wide Web. Its primary function is to estab-
lish a connection with a Web server and transmit HTML pages to the client
browser.
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