Watchguard Firebox X1000 Reference Manual page 146

CHAPTER 9: Glossary
134
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.
out-of-band (OOB)
A management feature that enables the management station to
communicate with the Firebox using a telephone line and a
modem. OOB is very useful for remotely configuring a Firebox
when Ethernet access is unavailable.
packet
A unit of information containing specific protocols and codes that
allow precise transmittal from one node in a network to another.
packet filtering
A way of controlling access to a network by analyzing the
incoming and outgoing packets and letting them pass or halting
them based on the IP addresses of the source and destination.
WatchGuard Firebox System