Eicon Networks SHIVA 1100, Administrator'S Manual, Page: 45 / 136

Chapter 4: Firewall
Chapter 4
Firewall
The Shiva VPN Gateway is equipped with a fully featured, stateful firewall. The firewall
allows you to control both incoming and outgoing access, so that computers on the
LAN can have tailored Internet access facilities and are shielded from malicious
attacks. By default the firewall is active, and allows all outgoing connections and
blocks all incoming connections.
The Shiva VPN Gateway's stateful firewall keeps track of outgoing connections (e.g.
a computer on your LAN requesting content from a server on the Internet) and only
allows corresponding incoming traffic (e.g. the server on the Internet sending the
requested content to the computer).
Sometimes it may be useful to allow some incoming connections, e.g. if you have a
mail or web server on your LAN that you want to be accessible from the Internet.
These situations are catered for by configuring Packet Filtering rules.
Generally, the majority of customizations to the default firewall rule set will be done
through Packet Filtering (page 49).