Notes About The Zywall Anti-Virus; General Anti-Virus Setup; Figure 118 Zywall Anti-Virus Example - ZyXEL Communications ZYWALL P1 User Manual

Figure 118 ZyWALL Anti-virus Example

The following describes the virus scanning process on the ZyWALL.
1 The ZyWALL first identifies SMTP, POP3, HTTP and FTP packets through standard
ports.
2 If the packets are not session connection setup packets (such as SYN, ACK and FIN), the
ZyWALL records the sequence of the packets.
3 The scanning engine checks the contents of the packets for virus.
4 If a virus pattern is matched, the ZyWALL "destroys" the file by removing the infected
portion of the file.
5 If the send alert message function is enabled, the ZyWALL sends an alert to the file's
indented destination computer(s).
Since the ZyWALL erases the infected portion of the file before sending it, you
may not be able to open the file.

12.2.2 Notes About the ZyWALL Anti-Virus

1 The ZyWALL anti-virus scanner cannot detect polymorphic viruses.
2 When a virus is detected, an alert message is displayed in Microsoft Windows
computers.
3 The ZyWALL does not scan the following file/traffic types:
• Simultaneous downloads of a file using multiple connections. For example, when you
use FlashGet to download sections of a file simultaneously.
• Encrypted traffic (such as on a VPN) or password-protected files.
• Traffic through custom (none-standard) ports.
• ZIP file(s) within a ZIP file.

12.3 General Anti-Virus Setup

Click SECURITY > ANTI-VIRUS to display the configuration screen as shown next.
1. For Windows 98/Me, refer to the
ZyWALL P1 User's Guide
1
Appendix F on page 453
Chapter 12 Anti-Virus
for requirements.
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