A digital signature scheme secure against adaptive chosen-message attacks
SIAM Journal on Computing - Special issue on cryptography
Universal one-way hash functions and their cryptographic applications
STOC '89 Proceedings of the twenty-first annual ACM symposium on Theory of computing
Efficient offline electronic checks (extended abstract)
EUROCRYPT '89 Proceedings of the workshop on the theory and application of cryptographic techniques on Advances in cryptology
Optimistic protocols for fair exchange
Proceedings of the 4th ACM conference on Computer and communications security
Efficient verifiable encryption (and fair exchange) of digital signatures
CCS '99 Proceedings of the 6th ACM conference on Computer and communications security
Communications of the ACM
The Design of Rijndael
Finite-state analysis of two contract signing protocols
Theoretical Computer Science
SIAM Journal on Computing
Abuse-Free Optimistic Contract Signing
CRYPTO '99 Proceedings of the 19th Annual International Cryptology Conference on Advances in Cryptology
CRYPTO '00 Proceedings of the 20th Annual International Cryptology Conference on Advances in Cryptology
A Digital Signature Based on a Conventional Encryption Function
CRYPTO '87 A Conference on the Theory and Applications of Cryptographic Techniques on Advances in Cryptology
A Practical Public Key Cryptosystem Provably Secure Against Adaptive Chosen Ciphertext Attack
CRYPTO '98 Proceedings of the 18th Annual International Cryptology Conference on Advances in Cryptology
ASIACRYPT '00 Proceedings of the 6th International Conference on the Theory and Application of Cryptology and Information Security: Advances in Cryptology
Optimistic Fair Exchange with Transparent Signature Recovery
FC '01 Proceedings of the 5th International Conference on Financial Cryptography
Simple and fast optimistic protocols for fair electronic exchange
Proceedings of the twenty-second annual symposium on Principles of distributed computing
RSA-OAEP Is Secure under the RSA Assumption
Journal of Cryptology
Correlating Topology and Path Characteristics of Overlay Networks and the Internet
CCGRID '06 Proceedings of the Sixth IEEE International Symposium on Cluster Computing and the Grid
How to win the clonewars: efficient periodic n-times anonymous authentication
Proceedings of the 13th ACM conference on Computer and communications security
Introduction to Modern Cryptography (Chapman & Hall/Crc Cryptography and Network Security Series)
Introduction to Modern Cryptography (Chapman & Hall/Crc Cryptography and Network Security Series)
Compositional analysis of contract-signing protocols
Theoretical Computer Science - Automated reasoning for security protocol analysis
Tor: the second-generation onion router
SSYM'04 Proceedings of the 13th conference on USENIX Security Symposium - Volume 13
SP '07 Proceedings of the 2007 IEEE Symposium on Security and Privacy
Making p2p accountable without losing privacy
Proceedings of the 2007 ACM workshop on Privacy in electronic society
Incentivizing outsourced computation
Proceedings of the 3rd international workshop on Economics of networked systems
Public-key cryptosystems based on composite degree residuosity classes
EUROCRYPT'99 Proceedings of the 17th international conference on Theory and application of cryptographic techniques
Optimistic fair exchange in a multi-user setting
PKC'07 Proceedings of the 10th international conference on Practice and theory in public-key cryptography
Legally-enforceable fairness in secure two-party computation
CT-RSA'08 Proceedings of the 2008 The Cryptopgraphers' Track at the RSA conference on Topics in cryptology
EUROCRYPT'05 Proceedings of the 24th annual international conference on Theory and Applications of Cryptographic Techniques
A fair protocol for signing contracts
IEEE Transactions on Information Theory
Optimistic fair exchange of digital signatures
IEEE Journal on Selected Areas in Communications
Distributing trusted third parties
ACM SIGACT News
| Hi-index | 0.00 |
Fairly exchanging digital content is an everyday problem. It has been shown that fair exchange cannot be achieved without a trusted third party (called the Arbiter). Yet, even with a trusted party, it is still non-trivial to come up with an efficient solution, especially one that can be used in a p2p file sharing system with a high volume of data exchanged. We provide an efficient optimistic fair exchange mechanism for bartering digital files, where receiving a payment in return for a file (buying) is also considered fair. The exchange is optimistic, removing the need for the Arbiter's involvement unless a dispute occurs. While the previous solutions employ costly cryptographic primitives for every file or block exchanged, our protocol employs them only once per peer, therefore achieving an O(n) efficiency improvement when n blocks are exchanged between two peers. Our protocol uses very efficient cryptography, making it perfectly suitable for a p-2-p file sharing system where tens of peers exchange thousands of blocks and they do not know beforehand which ones they will end up exchanging. Therefore, our system yields up to one-to-two orders of magnitude improvement in terms of both computation and communication (40s vs. 42min, 1.6MB vs. 200MB). Thus, for the first time, a provably secure (and privacy-respecting when payments are made using e-cash) fair exchange protocol can be used in real bartering applications (e.g., BitTorrent) [14] without sacrificing performance.