897 research outputs found
How to Watermark Cryptographic Functions
We introduce a notion of watermarking for cryptographic functions and propose a concrete scheme for watermarking cryptographic functions. Informally speaking, a digital watermarking scheme for cryptographic
functions embeds information, called a \textit{mark}, into functions such as one-way functions and decryption functions of public-key encryption. There are two basic requirements for watermarking schemes.
(1) A mark-embedded function must be functionally equivalent to the original function.
(2) It must be difficult for adversaries to remove the embedded mark without damaging the original functionality.
In spite of its importance and usefulness,
there have only been a few theoretical works on watermarking for functions (or programs). Furthermore, we do not have rigorous definitions of watermarking for cryptographic functions and concrete constructions.
To solve the above problem, we introduce a notion of watermarking for cryptographic functions and define its security. Furthermore, we present a lossy trapdoor function (LTF) based on the decisional linear (DLIN) problem and a watermarking scheme for the LTF. Our watermarking scheme is secure under the DLIN assumption in the standard model. We use techniques of dual system encryption and dual pairing vector spaces (DPVS) to construct our watermarking scheme. This is a new application of DPVS.
Our watermarking for cryptographic functions is a generalized notion of copyrighted functions introduced by Naccache, Shamir, and Stern (PKC 1999) and our scheme is based on an identity-based encryption scheme whose private keys for identities (i.e., decryption functions) are marked, so our technique can be used to construct black-box traitor tracing schemes
Aspects of a Watermark Solution
Although watermarking is a relatively new technology, there are many ways of applying it on an electronic data set with the purpose of ensuring copyright integrity and authenticity of the electronic data. But, bearing in mind the evolution of information technology and of communication, a watermark may be the target of several attacks which aim at its robustness, its form and even at its removal. In order to reduce these threats, this paper proposes a solution - digital watermarking completed by a hash function which has an important role in the authenticity of the content of a message and in the security of the transmission of this message through computer networks which are the main support of collaborative systems.Digital Watermarking, Hash Functions, Digital Information Security, Collaborative Systems
Improving random number generators by chaotic iterations. Application in data hiding
In this paper, a new pseudo-random number generator (PRNG) based on chaotic
iterations is proposed. This method also combines the digits of two XORshifts
PRNGs. The statistical properties of this new generator are improved: the
generated sequences can pass all the DieHARD statistical test suite. In
addition, this generator behaves chaotically, as defined by Devaney. This makes
our generator suitable for cryptographic applications. An illustration in the
field of data hiding is presented and the robustness of the obtained data
hiding algorithm against attacks is evaluated.Comment: 6 pages, 8 figures, In ICCASM 2010, Int. Conf. on Computer
Application and System Modeling, Taiyuan, China, pages ***--***, October 201
Randomness Quality of CI Chaotic Generators: Applications to Internet Security
Due to the rapid development of the Internet in recent years, the need to
find new tools to reinforce trust and security through the Internet has became
a major concern. The discovery of new pseudo-random number generators with a
strong level of security is thus becoming a hot topic, because numerous
cryptosystems and data hiding schemes are directly dependent on the quality of
these generators. At the conference Internet`09, we have described a generator
based on chaotic iterations, which behaves chaotically as defined by Devaney.
In this paper, the proposal is to improve the speed and the security of this
generator, to make its use more relevant in the Internet security context. To
do so, a comparative study between various generators is carried out and
statistical results are given. Finally, an application in the information
hiding framework is presented, to give an illustrative example of the use of
such a generator in the Internet security field.Comment: 6 pages,6 figures, In INTERNET'2010. The 2nd Int. Conf. on Evolving
Internet, Valencia, Spain, pages 125-130, September 2010. IEEE Computer
Society Press Note: Best Paper awar
New security and control protocol for VoIP based on steganography and digital watermarking
In this paper new security and control protocol for Voice over Internet
Protocol (VoIP) service is presented. It is the alternative for the IETF's
(Internet Engineering Task Force) RTCP (Real-Time Control Protocol) for
real-time application's traffic. Additionally this solution offers
authentication and integrity, it is capable of exchanging and verifying QoS and
security parameters. It is based on digital watermarking and steganography that
is why it does not consume additional bandwidth and the data transmitted is
inseparably bound to the voice content.Comment: 8 pages, 4 figures, 1 tabl
Constructing practical Fuzzy Extractors using QIM
Fuzzy extractors are a powerful tool to extract randomness from noisy data. A fuzzy extractor can extract randomness only if the source data is discrete while in practice source data is continuous. Using quantizers to transform continuous data into discrete data is a commonly used solution. However, as far as we know no study has been made of the effect of the quantization strategy on the performance of fuzzy extractors. We construct the encoding and the decoding function of a fuzzy extractor using quantization index modulation (QIM) and we express properties of this fuzzy extractor in terms of parameters of the used QIM. We present and analyze an optimal (in the sense of embedding rate) two dimensional construction. Our 6-hexagonal tiling construction offers ( log2 6 / 2-1) approx. 3 extra bits per dimension of the space compared to the known square quantization based fuzzy extractor
- …