ZyXEL Communications Prestige 642 User Manual page 128

Prestige 642 ADSL Internet Access Router
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 2 or more computers together so that they can share resources, you
have a computer network. Connect 2 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 PAP 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 Prestige routers (not all).
Port An Internet port refers to a number that is part of a URL, appearing after a colon (:) right after
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 becomes the standard and no further comments or changes are
permitted. Change can occur, however, through subsequent RFCs.
D
Glossary