Introduction To Broadband Router Technology; Introduction To Firewalls - D-Link DI-804 User Manual

Introduction to Broadband Router Technology

A router is a device that forwards data packets from a source to a
destination. Routers work on OSI layer 3, which forwards data packets using
an IP addresses and not a MAC address. A router will forward data from the
Internet to a particular computer on your LAN.
The information that makes up the Internet gets moved around using
routers. When you click on a link on a web page, you send a request to a
server to show you the next page. The information that is sent and received
from your computer is moved from your computer to the server using
routers. A router also determines the best route that your information should
follow to ensure that the information is delivered properly.
A router controls the amount of data that is sent through your network
by eliminating information that should not be there. This provides security
for the computers behind your router because computers from the outside
can not access or send information directly to any computer on your network.
The router determines which computer the information should be forwarded
to and sends it. If the information is not intended for any computer on your
network, the data is discarded. This keeps any unwanted or harmful
information from accessing or damaging your network.

Introduction to Firewalls

A firewall is a device that sits between your computer and the Internet
that prevents unauthorized access to or from your network. A firewall can be
a computer using firewall software or a special piece of hardware built
specifically to act as a firewall. In most circumstances, a firewall is used to
prevent unauthorized Internet users from accessing private networks such as
corporate LAN's and Intranets.
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