Although the transactions on the Bitcoin blockchain have the main purpose of recording currency transfers, they can also carry a few bytes of metadata. A sequence of transaction metadata forms a subchain of the Bitcoin blockchain, and it can be used to store a tamper-proof execution trace of a smart contract. Except for the trivial case of contracts which admit any trace, in general there may e...

In this paper, adapting a novel dual authentication method based on smart cards in public networks is proposed. This method uses the ElGamal public key cryptosystem and extend Chaum–van Antwerpen’s scheme to authenticate a signature between the signer and verifier using a dual protocol with a smart card that has tamper-resistant features. We propose the method to change the verification and dis...

We explore a new man-in-the-middle adversarial model for multi-prover interactive proofs (MIPs), and construct round-optimal, unconditionally secure, non-malleable MIPs. We compile from a large sub-class of Σ-protocols to a non-malleable MIP, avoiding the use of expensive NP-reductions to Graph Hamiltonicity or other NP-complete problems. Our compiler makes novel use of non-malleable codes – in...

After the terror attacks of 9/11, the U.S. Congress passed legislation that requires in the US Visa Waiver Program to begin issuing issuing machine readable passports that are tamper resistant and incorporate biometric and document authentication identifiers. The International Civil Aviation Organization (ICAO) has issued specifications for Machine Readable Travel Documents (MRTD) that are equi...

In a complex, smart card based system this feature turns smart cards from passive datastorage devices into active computational units. In fact they contain a tamper resistant secure one-chip microcomputer able to execute various cryptographic functions. Moreover, their potential can be extended after the issuance of the card by uploading various new applications. However, the limited resources ...

High-tech goods counterfeiting, multimedia content copying, and identity theft are all major concerns today. The proven cryptographic protocols implemented in Atmel’s tamper-resistant microcontrollers offer a powerful turnkey solution to fight these threats. This paper presents examples of efficient and cost effective IP protection applications utilizing secure chips in various embedded systems.

It is relatively easy to build an encryption system that is secure if it is working as intended and is used correctly but it is still very hard to build a system that does not compromise its security in situations in which it is either misused or one or more of its sub-components fails (or is ’encouraged’ to misbehave) . . . this is now the only area where the closed world is still a long way a...

We apply cryptographic techniques to the problem of fraud in metered mail. We describe a mail system that combines off-the-shelf barcode technology, tamper-proof devices, and cryptography in a fully-integrated secure franking system. This system provides protection against: 1. Tampering with postage meters to fraudulently obtain extra postage; 2. Forging and copying of stamps; 3. Unauthorized u...

Resilient modulus of pavement materials is a key property required for the pavement thickness design. This paper describes the results of an experimental study on the effects of temperature and loading frequency on the resilient modulus of a SBS polymer modified asphalt concrete under dry and saturated conditions. Dynamic creep tests were conducted on dry and saturated specimens of the mixture ...

A major challenge in software protection is the problem of tampering where an adversary modifies a program and uses it in a way that was not intended or desired. Several ad hoc techniques for software tamper resistance have been proposed, some of which provide a significant level of resilience against tampering. However, the literature lacks a formal definition of tampering that takes into acco...