User guide

CHAPTER 11: Glossary
158 WatchGuard Firebox System 6.0
behind the firewall based on the original destination port number.
Also called static NAT.
port space probe
An intrusion measure in which a hacker sequentially attacks port
numbers. These probes are usually attempts to map port space to
look for security holes which the sender might exploit.
port, TCP or UDP
A TCP or UDP service endpoint. Together with the hosts’ IP
addresses, ports uniquely identify the two peers of a TCP
connection.
PPP (Point-to-Point Protocol)
A link-layer protocol used to exchange IP packets across a point-
to-point connection, usually a serial line.
PPPoE (Point-to-Point Protocol over Ethernet)
A specification for connecting the users on an Ethernet to the
Internet through a common broadband medium.
PPTP (Point-to-Point Tunneling Protocol)
A VPN tunnelling protocol with encryption. It uses one TCP port
(for negotiation and authentication of a VPN connection) and one
IP protocol (for data transfer) to connect the two peers in a VPN.
Pretty Good Privacy (PGP)
An application and protocol (RFC 1991) for secure email and file
encryption. PGP uses a variety of algorithms, like IDEA, RSA,
DSA, MD5, SHA-1, for providing encryption, authentication,
message integrity, and key management.
primary key (IPSec)
An IPSec key responsible for creating a security association.
Values can be set in time or data size.
principle of precedence
Rules that determine which permissions and prohibitions
override which others when creating a combination of security
policies.