Internet host SMTP server survey 2003-11

Greetings,

This survey was carried out between 2003-10-31 and 2003-11-06.

I looked up PTR records for 1000000 random non-RFC1918 IP addresses. 
65350 of them had PTR records. Evidently the Internet now has about 278
million IP addresses with PTR records. For comparison: djb's previous survey
two years ago found 39206 addresses with PTR records out of 1000000 random
addresses.

I tried to connect to each address at the SMTP port:

  57991 connections timed out;
   6327 were refused;
      6 were dropped;
     44 were rejected with code 572;
      4 were rejected with code 421;
     20 were rejected with other result codes or no proper SMTP result code
     37 were reset.

There were 921 successful connections, a slight decrease from djb's survey of
two years ago.

I then sent a series of SMTP commands to each server, and fed the responses 
through a script that guesses what SMTP software is running on each host.

A few notes:

  Exim is catching up to Postfix; neither is close to qmail.
  4 of the qmail servers were running qpsmtpd instead of qmail-smtpd.
  3 of the qmail servers were running mailfront-smtpd instead of qmail-smtpd.
  Only 1 server didn't understand the EHLO command.  ESMTP is now essentially
    standard.
  
Here are the software tallies:

342 (37.1%) : sendmail     
157 (17.0%) : qmail     
142 (15.4%) : microsoft     
 55 (6.0%) : imail     
 47 (5.1%) : unknown / unidentifiable
 38 (4.1%) : postfix     
 36 (3.9%) : exim     
 28 (3.0%) : unknown (*****)    
 10 (1.1%) : mdaemon     
  9 (1.0%) : argosoft     
  7 (0.8%) : groupwise     
  6 (0.7%) : icewarp     
  5 (0.5%) : stalker     
  4 (0.4%) : lotusdomino     
  3 (0.3%) : smap     
  3 (0.3%) : postoffice     
  3 (0.3%) : ntmail     
  3 (0.3%) : mercur     
  3 (0.3%) : interscan viruswall    
  2 (0.2%) : WebSTAR     
  2 (0.2%) : pmdf     
  2 (0.2%) : mercury     
  1 (0.1%) : YellowTuna     
  1 (0.1%) : vpop3     
  1 (0.1%) : psc multinet (PMDF?)   
  1 (0.1%) : Perl SMTP::Server    
  1 (0.1%) : norton     
  1 (0.1%) : misconfigured HTTP server   
  1 (0.1%) : mailmarshal     
  1 (0.1%) : LSMTP/Windows     
  1 (0.1%) : interchange     
  1 (0.1%) : eudora     
  1 (0.1%) : Don's elisp SMTP daemon  
  1 (0.1%) : dmail     
  1 (0.1%) : checkpoint     
  1 (0.1%) : applemailserver     

Charles
-- 
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Charles Cazabon                                <[email protected]>
GPL'ed software available at:         http://www.qcc.ca/~charlesc/software/
Read http://www.qcc.ca/~charlesc/writings/12-steps-to-qmail-list-bliss.html
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