In this paper, we give the definition of the bit commitment channel, implement its formulization, prove the implementation of the zero-knowledge proof with with it and introduce four schemes of implementing the bit commitment channel. It is suggested that zero-knowledge proof algorithm can bebased on bit commitment channel and an instance for this is given.
In this note, we consider the problem of verifying the identity of an individual involved in a two party communication activity using a well-known Zero Knowledge protocol for a computationally intractable problem. This problem is the problem of coloring the vertices of a graph using three colors so that no pair of adjacent vertices receives the same color also known as 3-coloring problem. This problem is NP-complete, i.e. ít shares with a multitude of other natural combinatorial problems the property that most likely no fast (polynomial) algorithm exists for their solution. In this note, we use randomly generated 3-colorable graphs and use the knowledge of a 3-coloring of them to authenticate individuals. We exploìt the fact that one may easily generate a random 3-colorable graph with a specific 3-coloring that only he/she knows although it is a computationally intractable problem for someone who wants to impersonate the individual to discover a 3-coloring. Therefore, knowledge of a 3-coloring of a graph provides authentication of the individual possessing this knowledge. To prove this knowledge, the individual may use an adaptation of a Zero Knowledge Interactive proof protocol for 3-coloring.
An identification scheme based on a generator matrix of error-correcting codes over GF(q) is proposed, it is proved that the given protocol is a zero-knowledge interactive proof in the random oracle model, and it is shown that the scheme is secure when parameters are selected properly.
In this paper, we introduce the concept of subliminal channels with its historical background and the major application as it being a kind of information hiding technology. We give the meaning of closing subliminal channels. After analyzing some failed schemes for closing subliminal channels, wepresent an improved Chaum's zero-knowledge proof protocol and a divertible protocol which can close the known subliminal channels.
Advanced Steganography and Watermarking Techniques
Magdi El-Soudani, Heba S. El-Refaey, Hebat-Allah M. Mourad
Zero knowledge proofs form an important category in the public key identification protocols, they are depending on number theory. In 1989, Stern announced his protocol which is based on syndrome-decoding problem, he also studied the attacks against this type of problems. In this paper, we propose a broadcasting variant based on the Stern’ s Identification scheme. Broadcasting is applied when there are one prover and many verifiers. In the proposed broadcasting scheme, the prover is communicating with verifiers through a broadcasting channel so he is running the identification session once, which minimizes the time and the communication complexity. We have developed Stern basic scheme to be adequate for broadcasting applications, but the underlying hard problem that the security of Stern identification scheme depends on, is used as it is.
A new electronic cash scheme based on zero knowledge proof is proposed Unlike the other proposed schemes,our electronic cash scheme is not based on any specific scheme Thus we have provided an approach to construct electronic cash with any blind signature scheme or zero knowledge proof system The security of our scheme is proved based on some cryptographic assumptions
We describe a general technique to simplify as well as to improve several lattice based cryptographic protocols. The technique is rather straightforward and is easily applied to the protocols, and gives both a simpler analysis and better performance than the original protocols. The improvement is global: the modified protocols are simpler, faster, require less storage, use less bandwidth and need less random bits than the originals. Moreover, the improvement is achieved without any loss in security: we formally prove that the modified protocols are at least as secure as the original ones. In fact, the modified protocols might even be more secure as the adversary gets less information. We exemplify our technique on the Goldreich-Goldwasser zero-knowledge proof systems for lattice problems and the GGH public key cryptosystem. Partially supported by DARPA grant DABT63-96-C-0018 and NTT grant 67627-00. 1 1 Introduction Various cryptographic protocols based on the hardness of la...
Cryptography and Data Security
DNA and Biological Computing
Advanced Steganography and Watermarking Techniques