Messages in this thread | | | From | "Kevin M. Bealer" <> | Subject | [ samizdat, offtopic ] Re: I2O | Date | Tue, 22 Jul 1997 22:44:50 -0400 |
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"Russell Coker - mailing lists account" wrote: > Here's the date and sum info for the I2O doco. If they are tagging the >documents as someone suggested then the differences should show up in sum >output. Let me know if you have downloaded a version from the primary FTP >site which gets different sum output to mine. > > >rjc@wendy:/usr/local/ftp/pub/staff/rjc/I2O$l >total 1934 >drwxr-xr-x 2 archive anonftp 1024 Jul 20 23:38 . >drwxr-xr-x 3 archive anonftp 1024 Jul 20 23:38 .. >-rw-r--r-- 1 archive anonftp 1968945 Mar 12 10:00 ver1-5.pdf >rjc@wendy:/usr/local/ftp/pub/staff/rjc/I2O$sum * >52137 1923 >
Note that you just identified the "otherwise anonymous" engineer. I2O could look at these numbers and figure out which copy of the specs you have. (In this case I imagine they already know which copy was "dropped", assuming they care, assuming they have multiple independant copies to begin with. It has been there quite some time last I checked.)
I don't think there is any simple way to prevent tracking of such documents. They can not only insert whitespace, but typos, and even flip perfectly legitimate words between two spellings.
There is a grey area in the color coding of the disc drive. There is a gray area in the colour coding of the disk drive.
A spell checker or even a careful proof reader would not catch these flips most of the time, and this is straight text... Thus even printing a document is not a safety feature, and as was pointed out, "pdf", "ps", et al could be given minor tweaks to make the horizontal rules longer/shorter, fiddle with the top margin (a perfectly decodable "hidden message protocol" on a long document, assuming it doesn't get hand photocopied or something.)
hidden message protocol, or subliminal channel - you can hide a bit of information in every "flippeable" feature of a document, or 7/8 of a bit if you want error detection ;), so on a long document, you could even write the person's name into the text, assuming you have automatic "text feature flippability detection".
--kmb203@psu.edu----------------Debian/GNU--1.3---Linux--2.0.30--- OK, so you're a Ph.D. Just don't touch anything.
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