---------- Forwarded message ---------- Date: Sat, 22 Dec 2001 09:48:44 -0500 From: Niels Provos <provos@citi.umich.edu> To: Harald Koch <chk@pobox.com> Cc: cryptography@wasabisystems.com Subject: Re: Stegdetect 0.4 released and results from USENET search available In message <18592.1008992245@eloise.cfrq.net>, Harald Koch writes:

How many images are posted to usenet every *day*, never mind the sheer number of images stored on webservers everywhere. IANAS, but a mere one million messages is too small a sample set to be statistically significant. Herald,

thank you for the kind consideration of our work. How many images are posted to Usenet every day? I'd say around 50,000 a day, including GIF images and other image file types that we did not look at [1]. Which USENET archive that stores a full feed from the time before steganography suddenly hit the limelight of the press would you use? We had access to a couple of Terra bytes accounting for a few months of Usenet activity. Thats what we looked at. You might have heard that Usenet traffic is mostly for binary data. That is correct but most of the binary traffic is not in images [2]. If you have any suggestions on how to increase the scope of our analysis, I would be glad to hear them. Alternatively, you might conduct a study yourself as I just released most of my tools. It would be interesting to see something more "statistically significant" ;) Regards, Niels Provos. [1] http://www.newsadmin.com/cgi-bin/msgsummary [2] http://www.newsadmin.com/top100bytes.htm --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majordomo@wasabisystems.com