Web Anti-Virus
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9.2. Configuring Web Anti-Virus
Web Anti-Virus scans all objects that are loaded on your computer via the HTTP
protocol, and monitors any WSH scripts (JavaScript or Visual Basic Scripts, etc.)
that are run.
You can configure Web Anti-Virus settings to increase component operation
speed, specifically:
•
Set the scanning algorithm by selecting a complete or limited set of threat
signatures
•
Creating a list of trusted web addresses
It is also possible to select the actions that Web Anti-Virus will take in response
to discovering dangerous HTTP objects.
The following sections examine these settings in detail.
9.2.1. Setting a scan method
You can scan data from the Internet using one of the following algorithms:
•
Streaming scan
– this method for detecting malicious code in network
traffic scans data on the fly: as a file is downloading from the Internet,
Web Anti-Virus scans the file’s portions as they are downloaded, which
delivers the scanned object to the user more quickly. At the same time, a
limited set of threat signatures is used to perform streaming scans (only
the most active threats), which significant lowers the security level for
using the Internet.
•
Buffering scan
– this method scans objects only after they have been fully
downloaded to the buffer. After the scan is complete, the program either
passes the object to the user or blocks it.
When using this scan type, the full threat signature set is used, which
improves the level of malicious code detection. However, using this
algorithm increases object processing time, and hence makes web
browsing slower: it can also cause problems when copying and
processing large objects because the connection with the HTTP client can
time out.
One way to solve this problem is to limit the caching time for object
fragments downloaded from the Internet. When the time limit expires, the
user will receive the downloaded part of the file without it being scanned,
but once the object is fully copied, it will be scanned in its entirety. This
can deliver the object to the user sooner, and can solve the problem of
