What You Need To Know - ZyXEL Communications NXC5200 User Manual

Chapter 20 Anti-Virus

20.1.2 What You Need to Know

The following terms and concepts may help as you read this chapter.
Anti-Virus Engines
Subscribe to signature files for ZyXEL's anti-virus engine or one powered by
Kaspersky. When using the trial, you can switch from one engine to the other in
the Registration screen. After the trial expires, you need to purchase an iCard for
the anti-virus engine you want to use and register it in the Registration >
Service screen. You must use the ZyXEL anti-virus iCard for the ZyXEL anti-virus
engine and the Kaspersky anti-virus iCard for the Kaspersky anti-virus engine. See
Chapter 8 on page 151
Virus and Worm
A computer virus is a small program designed to corrupt and/or alter the
operation of other legitimate programs. A worm is a self-replicating virus that
resides in active memory and duplicates itself. The effect of a virus attack varies
from doing so little damage that you are unaware your computer is infected to
wiping out the entire contents of a hard drive to rendering your computer
inoperable.
NXC Anti-Virus Scanner
The NXC has a built-in signature database. Setting up the NXC between your local
network and the Internet allows the NXC to scan files transmitting through the
enabled interfaces into your network. As a network-based anti-virus scanner, the
NXC helps stop threats at the network edge before they reach the local host
computers.
You can set the NXC to examine files received through the following protocols:
• FTP (File Transfer Protocol)
• HTTP (Hyper Text Transfer Protocol)
• SMTP (Simple Mail Transfer Protocol)
• POP3 (Post Office Protocol version 3)
• IMAP4 (Internet Message Access Protocol version 4)
How the NXC Anti-Virus Scanner Works
The following describes the virus scanning process on the NXC.
The NXC first identifies SMTP, POP3, IMAP4, HTTP and FTP packets through
1
standard ports.
288
for details.
NXC5200 User's Guide