Smaller anti-virus efforts, such as the new ones from companies like SonicWall and WatchGuard, really cant keep up with this. And in many cases their techniques cant be as thorough, especially when trying to perform heuristic analysis.
Consider the new SonicWall gateway-level protection, which inspects at a packet level. Theres no way you can get a big-enough picture at this level to do heuristic analysis. Beefier boxes, like the Servgate Edgeforce line, which are actually Linux PCs with hard disks in them, can view entire files and do more sophisticated analysis. The Servgate boxes run McAfees anti-virus software. Like the SonicWall boxes, they also provide firewall protection, VPN and many other functions.
Gateway-level anti-virus from different vendors often differs in other subtle, but important ways. Does the system scan only SMTP or does it also scan POP3, in case a user inside the LAN checks an outside server? Does it scan IMAP (not that many people care)? Does it scan outbound traffic?
Unfortunately, you get what you pay for, and this kind of high-quality anti-virus gateway enforcement doesnt come cheap. Good protection is not the sole province of the Big Three. Kaspersky, Sophos, Bitdefender and others all have good products. But small companies trying to do their own scanners are just not in their league.
Security Center Editor Larry Seltzer has worked in and written about the computer industry since 1983.
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