This paper proposes a simple method that equips UMTS-based telecom companies with a mechanism to prove the records on mobile users’ phone bills. In the history of mobile phone communication, we have seen countless unsettled disputes where the mobile user disagrees with the telecom company either on the calling time or on the duration, or even on whether or not a call was actually made. In this ...

In this paper, we introduce a new electronic money methodology: sub-contracting the blinding to a trustee and using an Identitybased piece of information to achieve provable privacy and security. This variation on the Brickel, Gemmel and Kravitz paradigm [2] offers protection against various attacks minimizing user’s computational requirement. Furthermore, our scheme offers various complexity/p...

To achieve secure data communications, two parties should be authenticated by each other and agree on a secret session key by exchanging messages over an insecure channel. In this paper, based on the bilinear pairing, we present a new two-party authenticated key agreement protocol, and use the techniques from provable security to examine the security of our protocol within Bellare-Rogaway model.

This paper deenes a congruence relation on Gamma programs. Based on this congruence relation, laws for transforming programs are derived. We deene an axiomatic semantics for Gamma based on Brookes' transition assertions. The deenition of the congruence is in terms of provable satissability of such assertions. We consider the relationship between our congruence and other orderings that have been...

A simple and efficient shuffling scheme containing two protocols is proposed. Firstly, a prototype, Protocol-1 is designed, which is based on the assumption that the shuffling party cannot find a linear relation of the shuffled messages in polynomial time. As application of Protocol-1 is limited, it is then optimised to Protocol-2, which does not need the assumption. Both protocols are simpler ...

This essay relates to a recent article of Koblitz&Menezes that “criticizes several typical ‘provable security’ results” and argues that the “theorem-proof paradigm of theoretical mathematics is often of limited relevance” to cryptography. Although it should be obvious that these claims are utterly wrong, we undertake articulating this triviality. In particular, we point out some of the fundamen...

This is a proposal on the construction of a Message Authen-tication Code (MAC) based on Latin Squares. The design is inspired by Wegman-Carter construction which takes advantage of provable security. The MAC is described and its security is examined. It is also compared with other MACs and its advantages are shown.

In this paper we give an improved security analysis of the NESSIE submission BMGL. The new analysis improves also asymptotically some of the theoretical results on which the BMGL keystream generator is based. We also give an alternative, bootstrapped version of the generator which is implementation-wise very close to the original generator and offers even stronger provable security properties.

Public Key Encryption (PKE) scheme based on isogeny star has been proposed to be against the attack of the quantum computer for several years. But, there is no report about provable security PKE scheme based on isogeny star. In this paper, we propose a PKE scheme based on isogeny star and prove the security of the scheme in the random oracle.