User guide

CHAPTER 11: Glossary
154 WatchGuard Firebox System 6.0
non-seed router
A router that waits to receive routing information (the routing
maintenance table) from other routers on the network before it
begins routing packets.
NTP (Network Time Protocol)
An Internet service used to synchronize clocks between Internet
hosts. Properly configured, NTP can usually keep the clocks of
participating hosts within a few milliseconds of each other.
Oakley
The Oakley Session Key Exchange provides a hybrid Diffie-
Hellman session key exchange for use within the ISA/KMP
framework. Oakley provides the important property of Perfect
Forward Secrecy.
octet
A byte. Used instead of “byte” in most IP documents because
historically many hosts did not use 8-bit bytes.
one-time pad
A large, non-repeating set of truly random key letters used for
encryption, considered the only perfect encryption scheme.
one-way hash function
A function that produces a message digest that cannot be reversed
to produce the original.
Optional interface
An interface that connects to a second secured network, typically
any network of servers provided for public access.
Optional network
A network protected by the firewall but still accessible from the
Trusted and External networks. Typically, any network of servers
provided for public access.
OSI (Open Systems Interconnection)
A standard description or reference model for how messages
should be transmitted between any two points in a
telecommunication network. Its purpose is to guide product
implementors so that their products will consistently work with
other products.