Watchguard Firebox SOHO 6 Wireless, Руководство пользователя

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4 WatchGuard Firebox SOHO 6 Wireless
How does information travel on the Internet?
The data that is sent through the Internet is divided into packets.
To make sure that the packets are received at the destination,
information is added to the packets. The protocols for these tasks
are called TCP and IP. TCP disassembles and reassembles the data,
for example an email message or a program file. IP adds
information to the packets, which 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 Wireless 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.