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|---|---|
| From | Mok-Kong Shen <mok-kong.shen@t-online.de> |
| Newsgroups | uk.comp.security |
| Subject | A software for combining text files to obtain high quality pseudo-random sequences in practice |
| Date | Sun, 9 Jul 2017 12:13:37 +0200 |
| Organization | albasani.net |
| Lines | 25 |
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An estimate of entropy of English texts is 1.34 bits per letter [1]. This implies that, if the letters are coded into 5 bits, one needs to appropriately combine 4 text files in order to obtain bit sequences of full entropy, since 4*1.34 = 5.36 > 5. The method used in our software is to sum (mod 32) the coded values of a-z (mapped to 0-25) as 5 bits of the corresponding letters of the text files. There are plenty of other schemes for obtaining high quality pseudo-random sequences in practice, e.g. AES in counter mode. However our scheme seems to be much simpler both in the underlying logic (understandability) and in implementation and is thus a viable alternative that one could use/need under circumstances. The software, TEXTCOMBINE-SP, is available at mok-kong-shen.de [1] T. M. Cover, R. C. King, A Convergent Gambling Estimate of the Entropy of English, IEEE Trans. Inf. Theory, vol. 24, 1978, pp. 413-421. M. K. Shen
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A software for combining text files to obtain high quality pseudo-random sequences in practice Mok-Kong Shen <mok-kong.shen@t-online.de> - 2017-07-09 12:13 +0200
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