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Feb
2
revised Any efficient text-based steganographic schemes?
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Feb
2
comment Any efficient text-based steganographic schemes?
I guess that a weak point of translation-based stego is: Why should a sender send a (poor quality) translation and not the original so that the recipient could have it translated himself (there being facilities on the Internet) and also have the original to check in case ambiguities arise? That question might lead the warden to wonder under circumstances IMHO. On the other hand poor quality messages presumably could work well, if the sender is known to be fairly poor in language competence, e.g. an immigrant taking yet a language course.
Feb
2
comment Any efficient text-based steganographic schemes?
But the editing must have some sense at the superficial level and that would be difficult, wouldn't it? Wouldn't very frequent editing attract suspicions of the warden?
Feb
1
comment Any efficient text-based steganographic schemes?
Accidental trailing spaces are by definition rare. If a stego scheme capitlizes on exploiting trailing spaces, there would be lots of them to attract the warden's attention. Of course almost everything in the real world is connected with probabilities. There is barely 100% surety. One knows that even courts sometimes (have to) base their verdicts on the so-called presumptive evidences and thus occassionally innocent people go to jail because of that.
Feb
1
comment How to best obtain bit sequences from throwing normal dice?
I have computed the values of efficiencies for different number of rolls in increasing order (in parentheses is value of the method described by Thomas) up to 100 rolls: 1 1.66667 (1.33333), 2 2.33333 (2.22222), 4 2.38272, 7 2.53178 (2.40800), 12 2.57454 (2.54856), 24 2.57598, 36 2.57708, 48 2.57712, 53 2.58454 (2.57951)
Jan
31
awarded  Supporter
Jan
31
comment How to best obtain bit sequences from throwing normal dice?
The method you described for both single and two rolls are very fine for the practice, I believe. One just have to look up in a table to write down the bits. For three rolls, however, there is a drop in efficiency, if my computation is not in error. (For the method described by Thomas the efficiency of using 3 rolls is also less than that of using 2 rolls.)
Jan
31
comment What is a tweakable block cipher?
A major reference is: cs.berkeley.edu/~daw/papers/tweak-crypto02.pdf
Jan
30
comment How to best obtain bit sequences from throwing normal dice?
Perhaps I should add that an example of a "practical" question would be: If a random number in [0, 2^1024-1] is required, how should one best go about to generate it as a bit sequence through throwing normal dice?
Jan
30
asked How to best obtain bit sequences from throwing normal dice?
Jan
28
comment What is a smart card?
You have provided admirably plenty valuable informations. In a particular product: bsi.bund.de/SharedDocs/Downloads/DE/BSI/Zertifizierung/… there are stated: "The TOE provides full on-chip encryption covering the complete core, busses, memories and cryptographic co-processors leaving no plaintext on the chip." "No data in plain are handled anywhere on the TOE and thus also the two CPUs compute entirely masked and in addition dynamic mask changes are applied." Wouldn't that mean that homomorphic computations are being done there?
Jan
26
comment Cryptographic Symmetric Stream Cipher
What is the point of requiring two "independent" computers? Wouldn't one computer be sufficient in any case?
Jan
26
answered Any efficient text-based steganographic schemes?
Jan
25
comment Any efficient text-based steganographic schemes?
Concerning (2): With careful examination of inserted spaces at line-end etc., the warden can easily detect these. Thus they are insecure IMHO. I have myself designed a scheme using the number of words per line to transmit one stego-bit (EMAILSTEGANO in s13.zetaboards.com/crypto) but its stego-bit rate is very low. Much higher stego-bit rates would IMHO be badly needed in certain practical situations. I'll be very interested in schemes using the 3rd method you listed under (3) above. Do you happen to have a few references to them?
Jan
24
answered What is a block cipher?
Jan
23
comment Any efficient text-based steganographic schemes?
Right. But my previous comment was for encrypted stego bits. (Encryption is a necessity if a stego scheme is to be of any non-trivial usage in practice nowadays at least.)
Jan
23
comment Any efficient text-based steganographic schemes?
I doubt your point of 'user friendly'. Could you give some convincing examples or references containing such?
Jan
21
asked Any efficient text-based steganographic schemes?
Jan
20
asked Any implication of a Yale result to security of quantum cryptology?
Jan
16
awarded  Critic