Toshiba Tekbright 700P - Manual (Page 107)

108 Establishing an Internet Connection
Internet security and the firewall
5.375 x 8.375 ver 2.1
How the firewall works
The primary purpose of a firewall is to provide a single point
of entry where a defense can be implemented, allowing
access to the Internet from within the organization while
controlling access from the Internet to the Magnia SG20.
The firewall works by refusing nearly all direct access to your
Magnia SG20 from the Internet. No one may access any
application, file, or resource within your firewall from the
Internet, but any application (from the local network) may
access the Internet and conduct bidirectional access
transparently.
All access to the Internet is channeled through a single access
point on the server, called the gateway. The firewall
incorporated into this gateway is a set of programs designed
to deny access to your network from the outside unless access
has been granted. By refusing access to your local network
resources, the firewall prevents potentially damaging use of
your local network computers by outside sources.
The server’s firewall is active for all connections made on the
public Ethernet port (used for broadband connections to the
Internet) as well as all communications on the modem or
ISDN port (used for dial-up Internet connections). This
logically separates the server from “remote” access
equipment, but does not restrict access by local network
clients.