The first limitation of the database method is that it simply protects users against known viruses rather than proactively defending against new ones. When new viruses are created, it takes hours or even days for anti-virus companies to create patches and updates. This "lag" time allows the malicious programs to do tremendous damage before the new patch or update is released.

The second limitation of the database solution is that PDAs have limited file space compared to their PC counterparts. Therefore, the large databases that currently work for PCs may not fit on a PDA. Presently, the databases containing PDA viruses are relatively small because the number of known PDA viruses is also small. However, when the number of PDA viruses increases dramatically, the size of the anti-virus database for PDAs could quickly become too big to be stored on the device itself. Despite these limitations, McAfee and Symantec are both implementing a database solution for handheld devices, understandable, since that's the architecture of their desktop-based solutions.

McAfee VirusScan Wireless
McAfee VirusScan Wireless (at http://mcafeestore.beyond.com/Product/0,1057,3-18-ML100108,00.html) protects users' computers against viruses that may reside on a PDA resulting from unprotected synchronization. Its primary purpose is to protect corporate networks against viruses brought into the office by an employee via their PDA. The software doesn't run on the device itself, rather it's loaded on a user's PC and uses virus definitions in the database to automatically scan all files as they're passed to and from a PDA for known viruses when a user synchronizes.

VirusScan Wireless fulfills its primary purpose by protecting the network and the PDA during synchronization, but the program doesn't protect PDA users from downloading viruses directly to their handheld device via infrared beaming or network access (which makes the "wireless" part of the product name something of a misnomer). To keep the software current, it must be maintained through either automatic or manual updates, making the product less durable.

For Palm OS-based devices, VirusScan Wireless consists of both PC-resident and PDA-resident components. The piece of the product that goes on the PDA takes up only 3K of file space. This is very small compared to other software that resides on the PDA. Given the huge amounts of storage space on PCs today, the minimum system requirement of 10MB of hard-disk space is practically negligible. No matter how many new viruses appear, computers will be able to handle the extra storage space requirements.

Released in August of 2000, McAfee VirusScan Wireless was one of the industry's first full version virus security solutions offering protection from viruses transferred via PDA devices. The software is priced at $29.95 on the McAfee Web site. The VirusScan Wireless software was developed for use by non-technical consumers and is easy to install and use. Directions for setting what to scan, scheduling updates, or even deleting the application altogether take just a few simple steps.