Fortinet FortiGate 100A, Administration Manual

Page: 15 / 374

Introduction Spam filtering
FortiGate-100A Administration Guide 01-28007-0068-20041203
15
To prevent unintentionally blocking legitimate web pages, you can add URLs to an
exempt list that overrides the URL blocking and content blocking lists. The exempt list
also exempts web traffic this address from virus scanning.
Web content filtering also includes a script filter feature that can block unsecure web
content such as Java applets, cookies, and ActiveX.
Spam filtering
FortiGate spam filtering can scan all POP3, SMTP, and IMAP email content for spam.
You can configure spam filtering to filter mail according to IP address, email address,
mime headers, and content. Mail messages can be identified as spam or clear.
You can also add the names of known Real-time Blackhole List (RBL) and Open
Relay Database List (ORDBL) servers. These services contain lists of known spam
sources.
If an email message is found to be spam, the FortiGate adds an email tag to the
subject line of the email. The recipient can use the mail client software to filter
messages based on the email tag. Spam filtering can also be configured to delete
SMTP email messages identified as spam.
Firewall
The FortiGate ICSA-certified firewall protects your computer networks from Internet
threats. ICSA has granted FortiGate firewalls version 4.0 firewall certification,
providing assurance that FortiGate firewalls successfully screen and secure corporate
networks against a range of threats from public or other untrusted networks.
After basic installation of the FortiGate unit, the firewall allows users on the protected
network to access the Internet while blocking Internet access to internal networks.
You can configure the firewall to put controls on access to the Internet from the
protected networks and to allow controlled access to internal networks.
FortiGate policies include a range of options that:
• control all incoming and outgoing network traffic,
• control encrypted VPN traffic,
• apply antivirus protection and web content filtering,
• block or allow access for all policy options,
• control when individual policies are in effect,
• accept or deny traffic to and from individual addresses,
• control standard and user defined network services individually or in groups,
• require users to authenticate before gaining access,
• include traffic shaping to set access priorities and guarantee or limit bandwidth for
each policy,
• include logging to track connections for individual policies,
• include Network Address Translation (NAT) mode and Route mode policies,
• include mixed NAT and Route mode policies.
The FortiGate firewall can operate in NAT/Route mode or Transparent mode.