Jack Ungerleider wrote:
> 
> 
> > On Wed, 31 Jan 2007, Steve Siegfried wrote:
> >
> >> OS rankings published by OneStat.com on 14Aug2006:
> >>
> >>   > The 10 most popular operating systems in the world on the web are:
> >>   >
> >>   > 	1.  	Windows XP  		86.80%
> >>   > 	2. 	Windows 2000 		6.09%
> >>   > 	3. 	Windows 98 		2.68%
> >>   > 	4. 	Macintosh 		2.32%
> >>   > 	5. 	Windows ME 		1.09%
> >>   > 	6. 	Linux 			0.36%
> >>   > 	7. 	Windows NT 		0.24%
> >>   > 	8. 	Macintosh Power PC 	0.15%
> >>
> >> ...
> >>
> >>   > Methodology: A global usage share of xx percent
> >>   > for OS Y means that xx percent of the visitors
> >>   > of Internet users arrived at sites that are
> >>   > using one of OneStat.com's services by using the
> >>   > particular number of OS Y. All numbers mentioned
> >>   > in the research are averages and all measurements
> >>   > are normalised to the GMT timezone. Research is
> >>   > based on a sample of 2 million visitors divided
> >>   > into 20,000 visitors of 100 countries each day.
> >
> >
> > Is it possible that Linux machines don't identify as such?  I don't know
> > why a machine would give it's OS to a web site!  It seems like a bad idea,
> > so maybe Linux users avoid it.
> >
> > Linux definitely has more market share on the server, as you suggested.
> >
> 
> It would part of the HTTP_USER_AGENT value, which is a standard CGI
> environment variable. Its included as part of the HTTP REQUEST data. Do a
> Google search on "browser identification" there are several sites on the
> web that will feed the information back to you.
> 

I concur, it's probably done by looking a web browser HTTP_USER_AGENT
strings.


However, if you look at who _serves_ the pages instead of who _reads_
'em, it's quite a different story:

   >                         Top Developers
   >
   > Developer  December 2006   Percent January 2007    Percent  %_Change
   > Apache     63819607        60.64   64312083        60.17    -0.47
   > Microsoft  32277976        30.67   32898421        30.78     0.11
   > Sun         1763847         1.68    1749026         1.64    -0.04
   > Zeus        635673          0.60     551767         0.52    -0.08

Source: http://news.netcraft.com/archives/web_server_survey.html


Note that the Security Space "Research Reports" section reports slightly
different statistics:

   > January 1st, 2007
   >
   > Across All Domains
   >
   > Market Share Change (Total servers: 21,566,239)
   > 
   > SERVER     DEC. COUNT      DEC %   NOV COUNT       NOV %   CHANGE
   > Apache     15,785,782      73.20%  15,645,600      73.28%  -0.08%
   > Microsoft   4,383,008      20.32%   4,369,859      20.47%  -0.15%
   > Zeus          122,967       0.57%     132,276       0.62%  -0.05%
   > WebSTAR        97,982       0.45%      86,885       0.41%  +0.04%
   > Netscape       71,532       0.33%      70,557       0.33%  +0.00%
   > WebSite        10,579       0.05%      10,833       0.05%  +0.00%
   > Other       1,094,389       5.07%   1,034,155       4.84%  +0.23%

Source: http://www.securityspace.com/s_survey/data/200612/index.html

Methodology in both of these surveys seems to be web-crawlers and/or
HEAD requests.


So, Apache has roughly 60-70% of the market, at least twice that of
Microsoft.  How much of the Apache market runs what platform is tougher
to find out (read: I'm still looking).


BTW: http://www.securityspace.com has some interesting surveys, including
one on mail servers showing sendmail with 32% of the market, Microsoft
with 21% and the rest spread among other mail servers.

-S