User guide

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Glossary
Node—A point of concentrated communications; a central point of
communications.
Nonrepudiation—The condition when a receiver knows or has assurance that the
sender of some data did in fact send the data, even though the sender later might
want to deny ever having sent the data.
O
OSI—Abbreviation for the Open Systems Interconnection. Usually refers to the
7-layered protocol model for the exchange of information between open systems.
The 7 layers in order are physical, data-link, network, transport, session,
presentation, and application.
P
Packet—A sequence of data and control characters (binary digits) in a specified
formats that is switched/transferred as a whole.
PAP—Acronym for Password Authentication Protocol. An authentication protocol
that enables PPP peers to authenticate one another; it does not prevent
unauthorized access but merely identifies the remote end.
PCMCIA card—A credit card size memory or PC card that meets the PC Card
Standard developed jointly by the Personal Computer Memory Card International
Association (PCMCIA) and the Japan Electronic Industry Development Association
(JEIDA).
PKCS—Abbreviation for Public Key Cryptography Standard. A set of standards for
public key cryptography developed in cooperation with an informal consortium
(Apple, DEC, Lotus, Microsoft, MIT, RSA, and Sun) that includes algorithm specific
and algorithm independent implementation standards.
Point-to-point Tunneling Protocol (PPTP)—A TCP/IP technology used to create
virtual private networks or remote access links between sites or remote access.
PPTP is the work of a vendor group that includes Microsoft, 3Com, and Cooper
Mountain Networks. It is generally regarded as less secure than L2TP and is used
less frequently for that reason.
Policy—A broad statement of views and position. A policy states high-level intent
with respect to a specific area of security and is more properly called a security
policy.
Port number—A number carried in Internet transport protocols to identify which
service or program is supposed to receive an incoming packet. Examples are Web
services us port 80, email port 25, RADIUS uses either ports 1648-1649 or
1811-1812.
Pretty Good Privacy (PGP)—A shareware encryption technology for
communication that uses both public and private encryption technology to speed
up encryption without compromising security.