ZyXEL Communications Broadband Security Gateway P-312 - Manual (Page 245)

P312 Broadband Security Gateway
X Glossary
Plain Text The opposite of Cipher Text, Plain Text is readable by anyone.
Prestige Web
Configurator
This is a web-based Prestige router (not all) configurator that includes an Internet
Access Wizard, Advanced and Firewall (not all Prestige models) configurations.
POP Post Office Protocol. This is a common protocol used for sending, receiving, and
delivering mail messages.
Port (H/W) An interface on a computer for connecting peripherals or devices to the computer. A
printer port, for example, is an interface that is designed to have a printer connected to
it. Ports can be defined by specific hardware (such as a keyboard port) or through
software.
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.
Promiscuous
Packet Capture Actively capturing packet information from a network. Most computers only collect
packets specifically addressed to them. Promiscuous packet capture acquires all
network traffic it can regardless of where the packets are addressed.
Protocol A “language” for communicating on a network. Protocols are sets of standards or rules
used to define, format, and transmit data across a network. There are many different
protocols used on networks. For example, most web pages are transmitted using the
HTTP protocol.
Proxy Server A server that performs network operations in lieu of other systems on the network.
Proxy Servers are most often used as part of a firewall to mask the identity of users
inside a corporate network yet still provide access to the Internet. When a user
connects to a proxy server, via a web browser or other networked application, he
submits commands to the proxy server. The server then submits those same
commands to the Internet, yet without revealing any information about the system that
originally requested the information. Proxy servers are an ideal way to also have all
users on a corporate network channel through one point for all external
communications. Proxy servers can be configured to block certain kinds of
connections and stop some hacks.
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