P-662H/HW-D Series User’s Guide

This is an Internet file transfer service that operates on the Internet and over TCP/IP networks. A system running the FTP server accepts commands from a system running an FTP client. The service allows users to send commands to the server for uploading and downloading files.

Note: The anti-virus packet scan on the ZyXEL Device offers the first defense against possible virus attacks on your network. It is not a replacement of the anti-virus client software that you may install on network computers.

12.3.1 How the ZyXEL Device Virus Scan Works

The following describes the virus scanning process on the ZyXEL Device.

1The ZyXEL Device first identifies the packet types (SMTP, POP3, HTTP and FTP through standard ports only) from the network traffic.

2If the packets are not session connection setup packets (such as SYN, ACK and FIN), the ZyXEL Device records the sequence of the packets.

3The scanning engine scans the content of the packet for virus.

4If a virus pattern is matched, the ZyXEL Device “cleans” the virus by deleting the infected packet and alerts the intended computer user(s).

Note: Since the ZyXEL Device “destroys” a file by deleting the infected portion of the file content, you cannot open the file.

12.3.2 Limitations of the ZyXEL Device Packet Scan

The ZyXEL Device does not scan the following types of file for virus:

•Compressed or zipped files

•Simultaneous file downloads (for example, when you use the FlashGet download program).

•When a virus is detected, an alert message is displayed in Miscrosoft Windows-based operation systems only.1

12.4Anti-Virus Packet Scan Configuration

Note: Before you can use the anti-virus packet scan on the ZyXEL Device, you must register for the anti-virus service in the Registration and Virus Information Update screen (see the Section 12.5 on page 207 section for more information).

1. For Windows 98/Me, refer to the antivirus supplement for requirements.

Chapter 12 Anti-Virus Packet Scan

205