ZyXEL Communications Prestige 642M series, User Manual

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Prestige 642M Series ADSL Bridge
D Glossary
Multiplexor
Multiplexors or MUXs, as they are often called, are devices that combine signals from various
sources such as PBX (Private Branch Exchange), asynchronous terminals or a bridge connected
to a Wan. A multiplexor transmits these signals as a single data stream over a digital line.
Multiplexors, among other tasks, conserve bandwidth.
NAT
Network Address Translation is the translation of an Internet Protocol address used within one
network to a different IP address known within another network.
Network
Any time you connect two or more computers together, allowing them to share resources, you
have a computer network. Connect two or more networks together and you have an internet.
NIC
Network Interface Card. A board that provides network communication capabilities to and from
a computer system. Also called an adapter.
Node
Any single computer connected to a network.
PAP
Password Authentication Protocol is a security protocol that requires users to enter a password
before accessing a secure system The user’s name and password are sent over the wire to a
server where they are compared with a database of user account names and passwords. This
technique is vulnerable to wiretapping (eavesdropping) because the password can be captured
and used by someone to log onto the system.
PNC
Prestige Network Commander. A Windows-based setup wizard for some Prestige routers.
Port
An Internet port refers to a number that is part of a URL, appearing after a colon (:), directly
following the domain name. Every service on an Internet server listens on a particular port
number on that server. Most services have standard port numbers, e.g. Web servers normally
listen on port 80.
POTS
Plain Old Telephone Service is the analog telephone service that runs over copper twisted-pair
wires and is based on the original Bell telephone system. Twisted-pair wires connect homes and
businesses to a neighborhood central office. This is called the local loop. The central office is
connected to other central offices and long-distance facilities.
PPP
Point to Point Protocol. PPP encapsulates and transmits IP (Internet Protocol) datagrams over
serial point-to-point links PPP works with other protocols such as IPX (Internetwork Packet
Exchange). The protocol is defined in IETF (Internet Engineering Task Force) RFC 1661
through 1663. PPP provides router-to-router, host-to-router and host-to-host connections.
PSTN
Public Switched Telephone Network was put into place many years ago as a voice telephone
call-switching system. The system transmits voice calls as analog signals across copper twisted
cables from homes and businesses to neighborhood COs (central offices); this is often called the
local loop. The PSTN is a circuit-switched system, meaning that an end-to-end private circuit is
established between caller and callee.
PVC
Permanent Virtual Circuit. A PVC is a logical point-to-point circuit between customer sites.
PVCs are low-delay circuits because routing decisions do not need to be made along the way.
Permanent means that the circuit is preprogrammed by the carrier as a path through the network.
It does not need to be set up or torn down for each session.
RFC
An RFC (Request for Comments) is an Internet formal document or standard that is the result of
committee drafting and subsequent review by interested parties. Some RFCs are informational
in nature. Of those that are intended to become Internet standards, the final version of the RFC