AV-Comparatives is known for the thorough tests it does on security software. Following its May 2009 retrospective/proactive report, the company has released its August 2009 on-demand comparative. Sixteen products, last updated on August 10, were set on the same highest detection settings (except for Sophos and F-Secure) and put to the test.

There were two sets of malware: Set A, which contains malware from December 2007 to December 2008 (most products could detect over 97 percent), and Set B, which contains malware from the last seven months (1.6 million samples). The set included the following categories of malware: Trojans (69.5 percent), Backdoors/Bots (20.7 percent), Worms (6.1 percent), other malware (1.5 percent), Windows viruses (0.4 percent). Here are the results for Set B:

G DATA Antivirus 20.0.4.9: 99.8 percent AVIRA AntiVir Premium 9.0.0.446: 99.4 percent McAfee VirusScan Plus 13.11.102: 98.7 percent Symantec Norton Antivirus 17.0.0.136: 98.4 percent Avast Professional Edition 4.8.1348: 98.0 percent F-Secure Antivirus 10.00.246: 97.9 percent BitDefender Antivirus 13.0.13.254: 97.8 percent eScan AntiVirus 10.0.997.491: 97.7 percent Trustport Antivirus 2.8.0.3017: 97.6 percent ESET NOD32 Antivirus 4.0.437.0: 97.2 percent Kaspersky AntiVirus 9.0.0.463: 94.7 percent AVG Antivirus 8.5.406: 94.0 percent Sophos Antivirus 7.6.10: 91.3 percent Microsoft Windows Live OneCare 2.5.2900.28: 90.0 percent Kingsoft Antivirus 2009.08.05.16: 86.4 percent Norman Antivirus & AntiSpyware 7.10.02: 84.8 percent

Detection rates aren't the only thing that matters for an antivirus, though. The following graph shows missed malware samples (in percentage points) for each of the 16 products:

The second graph shows false alarms (number of detections that weren't actually malware) when scanning (on-demand) a set of clean files for each of the 16 products:

The final graph shows the throughput rate (in MB/sec) when scanning (on-demand) a set of clean files for the 16 products:

Using all of the above results, AV-Comparatives rated the security companies from best to worst in four separate categories:

Advanced+: G DATA, Symantec, Avast, F-Secure, BitDefender, eScan, ESET

Advanced: AVIRA, McAfee, TrustPort, Kaspersky, AVG

Standard: Microsoft

Tested: Sophos, Kingsoft, Norman

It's worth noting that the Microsoft solution tested here went the way of the dodo three months ago and in doing so, Redmond left the market for paid, consumer solutions. Microsoft Security Essentials, the company's free real-time consumer antimalware solution, is almost ready for release and is rumored to arrive as early as this week.