Ip Addresses; Protocols; Port Numbers - Watchguard Firebox SOHO 6 User Manual

How Information Travels on the Internet
and reassembles the data; for example, data that may consist of an
email message or a program file. IP adds information to the
packets that includes the destination and the handling
requirements.

IP addresses

An IP address identifies a computer on the Internet that sends and
receives packets. Each computer on the Internet has an address.
The SOHO 6 is also a computer and has an IP address. When you
configure a service behind a firewall, you must include the trusted
network IP address for the computer that supplies the service.
A URL (Uniform Resource Locator) identifies each IP address on
the Internet. An example of a URL is:
http://www.watchguard.com/.

Protocols

A protocol defines how a packet is assembled and transmitted
through a network. The most frequently used protocols are TCP
and UDP (User Datagram Protocol). There are other IP protocols
that are less frequently used.

Port numbers

During the communication between computers, port numbers
identify which programs or applications are connected.
User Guide 5