User`s guide

Chapter 11. Appendix C Glossary SL6000 ADSL Ethernet Router User’s Guide
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SNMP
Simple Network Management Protocol
The TCP/IP protocol used for network management.
splitter
A device that splits off the voice component of the DSL signal to
a separate line, so that data and telephone service each have
their own wiring and jacks. The splitter is installed by your
telephone company where the DSL line enters your home. The
CO also contains splitters that separate the voice and data
signals, sending voice to the PSTN and data on high-speed lines
to the Internet.
See also CO, PSTN, splitterless, microfilter
.
splitterless
A type of DSL installation where no splitter is installed, saving
the cost of a service call by the telephone company. Instead,
each jack in the home carries both voice and data, requiring a
microfilter for each telephone to prevent interference from the
data signal. ADSL is usually splitterless; if you are unsure if your
installation has a splitter, ask your DSL provider.
See also
splitter, microfilter
.
subnet
A subnet is a portion of a network. The subnet is distinguished
from the larger network by a
subnet mask
which selects some of
the computers of the network and excludes all others. The
subnet's computers remain physically connected to the rest of
the parent network, but they are treated as though they were on
a separate network.
See also network mask
.
subnet mask
A mask that defines a subnet.
See also network mask
.
TCP See TCP/IP
.
TCP/IP
Transmission Control Protocol/Internet Protocol
The basic protocols used on the Internet. TCP is responsible for
dividing data up into packets for delivery and reassembling them
at the destination, while IP is responsible for delivering the
packets from source to destination. When TCP and IP are
bundled with higher-level applications such as HTTP, FTP,
Telnet, etc., TCP/IP refers to this whole suite of protocols.
Telnet
An interactive, character-based program used to access a
remote computer. While HTTP (the web protocol) and FTP only
allow you to download files from a remote computer, Telnet
allows you to log into and use a computer from a remote
location.
TFTP
Trivial File Transfer Protocol
A protocol for file transfers, TFTP is easier to use than File
Transfer Protocol (FTP) but not as capable or secure.
TTL
Time To Live
A field in an IP packet that limits the life span of that packet.
Originally meant as a time duration, the TTL is usually
represented instead as a maximum hop count; each router that
receives a packet decrements this field by one. When the TTL
reaches zero, the packet is discarded.
twisted pair
The ordinary copper telephone wiring long used by telephone
companies. It contains one or more wire pairs twisted together to
reduce inductance and noise. Each telephone line uses one pair.
In homes, it is most often installed with two pairs. For Ethernet
LANs, a higher grade called Category 3 (CAT 3) is used for
10BASE-T networks, and an even higher grade called Category