User's Manual

Table Of Contents
Protocols
User Guide 3
share the same bandwidth. Because of this "shared-medium" topol-
ogy, cable modem users might experience somewhat slower network
access during periods of peak demand, and can be more susceptible
to certain types of attacks more than users with other types of con-
nectivity.
Digital Subscriber Line (DSL) Internet connectivity, unlike cable
modem-based service, provides the user with dedicated bandwidth.
However, the maximum bandwidth available to DSL users is usually
lower than the maximum cable modem rate because of differences
in their respective network technologies. Also, the "dedicated band-
width" is dedicated only between your home or office and the DSL
provider's central office. The provider offers little or no guarantee of
bandwidth across the Internet.
Internet Service Providers
(ISP) are companies that provide access to
the Internet.
Protocols
You will often hear the term protocol. A
protocol
is a specification
that allows computers to communicate across a network. In a way,
protocols define the grammar that computers use to communicate
with each other.
The standard protocol whenever you connect to the Internet is
called Internet Protocol (IP). This protocol can be thought of as the
common language of computers on the Internet.
A protocol also defines how data is assembled and transmitted
through a network. The most frequently used protocols are TCP
(Transmission Control Protocol) and UDP (User Datagram Protocol).
Other IP protocols are less commonly used.
TCP/IP is the basic protocol used by computers connected to the
Internet. TCP/IP involves certain settings that you need to know
when setting up your Firebox X Edge. For more information on TCP/
IP, see “Finding your TCP/IP properties” on page 13.
How Information Travels on the Internet
The data that is sent through the Internet is divided into units called
packets. When you send a file from one place to another on the