Universal one-way hash functions and their cryptographic applications
STOC '89 Proceedings of the twenty-first annual ACM symposium on Theory of computing
Proceedings of the 4th ACM conference on Computer and communications security
Composition and integrity preservation of secure reactive systems
Proceedings of the 7th ACM conference on Computer and communications security
Pseudorandomness and Cryptographic Applications
Pseudorandomness and Cryptographic Applications
Universally Composable Commitments
CRYPTO '01 Proceedings of the 21st Annual International Cryptology Conference on Advances in Cryptology
Time-Stamping with Binary Linking Schemes
CRYPTO '98 Proceedings of the 18th Annual International Cryptology Conference on Advances in Cryptology
Universally Composable Security: A New Paradigm for Cryptographic Protocols
FOCS '01 Proceedings of the 42nd IEEE symposium on Foundations of Computer Science
A Model for Asynchronous Reactive Systems and its Application to Secure Message Transmission
SP '01 Proceedings of the 2001 IEEE Symposium on Security and Privacy
Composition of Secure Multi-Party Protocols: A Comprehensive Study
Composition of Secure Multi-Party Protocols: A Comprehensive Study
Symmetric Encryption in a Simulatable Dolev-Yao Style Cryptographic Library
CSFW '04 Proceedings of the 17th IEEE workshop on Computer Security Foundations
Knowledge-binding commitments with applications in time-stamping
PKC'07 Proceedings of the 10th international conference on Practice and theory in public-key cryptography
Authentic time-stamps for archival storage
ESORICS'09 Proceedings of the 14th European conference on Research in computer security
Securing data accountability in decentralized systems
OTM'06 Proceedings of the 2006 international conference on On the Move to Meaningful Internet Systems: AWeSOMe, CAMS, COMINF, IS, KSinBIT, MIOS-CIAO, MONET - Volume Part I
Do broken hash functions affect the security of time-stamping schemes?
ACNS'06 Proceedings of the 4th international conference on Applied Cryptography and Network Security
| Hi-index | 0.00 |
We present a Universally Composable (UC) time-stamping scheme based on universal one-way hash functions. The model we use contains an ideal auditing functionality, the task of which is to check that the rounds' digests are correctly computed. Our scheme uses hash-trees and is just a slight modification of the known schemes of Haber-Stornetta and Benaloh-de Mare, but both the modifications and the audit functionality are crucial for provable security. We prove that our scheme is nearly optimal – in every UC time-stamping scheme, almost all time stamp requests must be communicated to the auditor.