Accountability in Electronic Commerce Protocols

In most commercial and legal transactions, the ability to hold individuals or organizations accountable for transactions is important. Hence, electronic protocols that implement commercial transactions must be designed to provide adequate accountability assurances for transacting parties. Without such assurances, electronic transactions can be susceptible to disputes. Currently, protocol design for electronic commerce is done in an ad-hoc manner, a technique which has been shown to be error-prone by past experience with key distribution protocols [4]. Despite the importance of accountability in electronic commerce, and the subtlety of designing error-free protocols, currently, there are no analysis methods to examine whether a protocol design conforms to the accountability goals of the transaction that it implements. Since most current protocol analysis methods have been developed to analyze key management protocols, they focus on properties such as message replay detection, and key or..

A Novel Logic for Analyzing Electronic Payment Protocols

A novel formal method which can be used to analyze security properties such as accountability, fairness and timeliness in electronic payment protocols is proposed. The novel method extends Qing-Zhou approach based on logic reasoning by adding a simple time expression and analysis method. It increases the ability to describe the event time, and extends the time characteristics of the logical inference rules. An anonymous electronic cash payment protocol is analyzed by the novel logic, and the result shows that the fairness of the protocol is not satisfied due to the timeliness problem in protocol. The novel logic method proposed in this paper has a certain theoretical and practical significance for the design and formal analysis of electronic payment protocols. At the same time, its idea has a certain guiding value for improving the security of other security protocols

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On the Security Effectiveness of Cryptographic Protocols

We introduce the notion of security effectiveness, illustrate its use in the context of cryptographic protocol analysis, and argue that it requires analysis of protocol property dependencies. We provide examples to show that, without dependency analysis, the use of some logics for cryptographic protocol analysis yields results that are inconsistent or unrealistic in practice. We identify several types of property dependencies whose use in protocol analysis methods can yield realistic analyses. Categories and Subject Descriptors: C.2.4 [Computer-Communication Networks]: General- Security and Protection, Distributed Systems; D.4.6 [Operating Systems]: Security and Protection - authentication, cryptographic controls; K.6.5 [Management of Computing and Information Systems]: Security and Protection - authentication; E.3 [Data]: Data Encryption. Key Words and Phrases: Security effectiveness, cryptographic protocol, cryptographic assumption, logic, dependency, threat countermeasure. 1 Intr..

Reasoning about Message Integrity

We propose an approach for reasoning about message integrity protection in cryptographic protocols. The set of axioms presented herein relate design parameters and assumptions of message integrity protection mechanisms to generic message integrity threats. Comparison of threat properties derived using these axioms with the policy goals for integrity protection aids in assessing the strength (or lack thereof) of message integrity protection mechanisms. We provide examples to illustrate the use of our approach in examining the weaknesses of message integrity protection mechanisms, and also in suggesting modifications in their design parameters. Categories and Subject Descriptors: C.2.4 [Computer-Communication Networks]: General - Security and Protection, Distributed Systems; D.4.6 [Operating Systems]: Security and Protection - cryptographic controls; E.3 [Data]: Data Encryption. Key Words and Phrases: Message integrity, integrity threshold, effective threshold, block membership, order..

Logics for Cryptographic Protocols - Virtues and Limitations

In this note we offer a perspective on the virtues and limitations of several logics for cryptographic protocols focusing primarily on the logics of authentication. We emphasize the scope limitations of these logics rather than their virtues because (1) we consider their virtues to be better understood and accepted than their limitations, and (2) we hope to stimulate further research that will expand their scope. 1 Introduction Advances in the formal analysis of authentication protocols, based primarily on the logic of authentication of Burrows, Abadi, and Needham [2,4], have stimulated interest in the development of new logics for analysis of other aspects of cryptographic protocols, such as message-meaning recognition [9,10] and message secrecy or privacy [6], not just for authentication. The use of these logics can be hampered, to some extent, by the difficulty of delimiting their usefulness in practical applications. The limited application scope of these logics can be easily misu..