Firewall
A hardware or software device that
prevents unauthorized access to a private
network from the Internet. The TG2492
provides a built-in firewall.
G
Gateway
The device, usually a router, that
connects devices on a given IP subnet to
other IP subnets.
H
Headend
The “central office” in an HFC network.
The headend houses both video and data
equipment. In larger cable networks, a
“master” headend often feeds several
“remote” headends to provide distributed
services.
HTTP
HyperText Transfer Protocol.
Hub
A box with several Ethernet connectors.
Ethernet hubs provide a common point of
contact for all connected devices.
I
IP address
A number assigned to your computer by
your cable company, used to identify your
computer to other systems on the
Internet.
ISDN
Integrated Services Digital Network. A
digital telephony standard that provides
communication speeds about twice as
fast as standard dialup.
L
LAN
Local Area Network. A network that
allows computers in a single location
(such as a building) to communicate with
one another.
LED
Light Emitting Diode. A semi-conductor
diode that emits light when current is
passed through it.
M
MAC address
A number that uniquely identifies any
device connected to a network. Your
cable company uses your Telephony
Gateway’s MAC address to authorize
access to the Internet. The MAC address
is printed on a label on the bottom of
your Telephony Gateway.
P
Protocol
A set of rules and formats that
determines the communication behavior
of network entities at a given layer.
Proxy
A device or program that stands in
between a server (for example, a web site)
and a client (your browser), providing a
way to relieve some of the burden from
the server. For example, your cable
company may have a web proxy that
keeps copies of popular web pages; the
proxy can send you those pages instead of
fetching them directly from the web site,
resulting in faster page loading and less
network congestion.
Release 24 STANDARD 1.1 March 2015
Touchstone TG2492 Telephony Gateway User Guide 41
Copyright ARRIS Enterprises, Inc. 2015. All Rights Reserved.