Subliminal Channels in Visual Cryptography

Subliminal Channels in Cryptographic Systems

Subliminal Visual Priming

Masked pictures of objects were flashed so briefly that only 13.5% of them could be named. Forced-choice accuracy for the unidentified objects was at chance. When the pictures were shown again, about 15 min and 20 intervening trials later, without any indication of possible repetitions, naming accuracy increased to 34.5%. The priming was completely visual, rather than semantic or verbal, as the...

The History of Subliminal Channels

In 1978 the United States was considering adopting a national security protocol designed to enable the U.S.S.R. to verify how many Minuteman missiles the United States had emplaced in a field of 1000 silos without revealing which silos actually contained missiles. For this protocol to have been acceptable to the U.S.S.R., the messages would have had to be digitally signed with signatures which ...

On Subliminal Channels in Deterministic Signature Schemes

Subliminal channels in randomized signature algorithms like the DSA are well-known. However, much less seems to be known about this issue when dealing with deterministic schemes. Using some known signature schemes like ESIGN-D and SFLASH as example, we illustrate the problem of subliminal channels in non-interactive deterministic signature algorithms. Based on an appropriate formalization, a de...

Exploring Subliminal Channels in Pairing-Based Signatures

The prisoners’ problem, introduced by Simmons in 1983, describes how two individuals attempt to communicate covertly by exploiting subliminal channels without alerting a ”warden” who controls the communication. Via subliminal channels it is possible to transmit covert messages by embedding them into cryptographic digital data (traditionally by exploiting randomness that is used in probabilistic...