Journal of Communications

Universal composable threshold signature

Qiang Li

Published Jan 1, 2009• 0 citations

Abstract

Threshold signature allowed any subset of t parties generating a signature,but that disallowed the creation of a valid signature if fewer than t parties participate in the protocol.Since the security of threshold signature was only con-sidered in a single instance before,the universal composability framework was introduced.The framework with its secu-rity preserving composition property allowed for modular design and analysis of the threshold signature.The defined ideal functionality of threshold signature is proved equals to the standard security notion of threshold signature.Further-more,how to applying the ideal functionality is described.The proposed threshold signature protocol and proactive threshold signature protocol are not only provably secure,but also universally composable.

Related papers

Adaptive Universal Composability Framework for Server-Aided Threshold Signature

Xuan Hong, Luqun Li

The threshold signature scheme is a protocol that allows any subset of t parties out of n to generate a signature. Since the t members can cooperate together to compute the secret key, we introduce the server-aided threshold signature, which provides controllability for activating the signing function in a certain enhanced way. In this study, we present a server-aided threshold RSA signature protocol against the adaptive attacks. We give the universally composable secure model for the server-aided threshold signature primitive and prove that the proposed protocol is claimed to be well-formed, correct and unforgeability. As a separate contribution we also prove that it is also secure in the adaptive universal composability framework. After the discussion about the security and the performance, we claim that the protocol is practical and efficient.

Research Journal of Applied Sciences Engineering and TechnologyJan 1, 20130 citations

Universally Composable Group Signature Protocol

ZHAO Chen,YU Huifang,LI Jianmin

At present,most group signature is only secure in the standard alone.Its security becomes weak in multiple protocol environment.In view of this,the security of group signature protocol is studied in the multiple concurrent execution under the universally composable framework.Since the protocol can be analyzed modularly under the universally composable framework,an ideal function of group signature protocol is defined in this framework.Then a group signature protocol is proposed to realize the ideal function,and its universally composable security as well as unforgeability is also proved.Furthermore,a concrete instance of this universally composable group signature protocol is given.Analysis results show that this protocol security is suitable for applications in multiple concurrent environment.

Mar 1, 20170 citations

Can universally composable cryptographic protocols be practical?

István Vajda

The Universal Composability (UC) framework provides provable security guaranties for harsh application environment, where we want to construct protocols which keep security guarantees even when they are concurrently composed with arbitrary number of arbitrary (even hostile) protocols.This is a very strong guarantee.The UC-framework inherently supports the modular design, which allows secure composition of arbitrary number of UC-secure components with an arbitrary protocol.In contrast, traditional analysis and design is a stand alone analysis where security of a single instance is considered, i.e. an instance which is not in potential interaction with any concurrent instances.Furthermore, a typical traditional analysis is informal, i.e. without a formal proof.In spite of these facts, beyond the task of key-exchange this technology have not really took the attention of the community of applied cryptography.From practitioner's point of view the UC-world may seem more or less an academic interest of theoretical cryptographers.Accordingly we take a pragmatic approach, where we concentrate on meaningful compromises between the assumed adversarial strength, ideality wishes and realization complexity while keeping provable security guarantees within the UC-framework.We believe that even modest but provable goals (especially, if tunable to application scenarios) are interesting if a wider penetration of the UC-technology is desired into the daily-practice of protocol applications.

International Journal of Computer Network and Information SecuritySep 8, 20152 citations

Universal composable security of multi-signature schemes

Zhibin Li

Since up to now the security of multi-signature protocols has only been considered in a single instance, the security of a multi-signature protocol when it is running with many other protocols concurrently was studied in the universal composable security framework. Firstly, the idea functionality of a multi-signature protocol was defined formally. Then, based on Waters' signature scheme, a multi-signature protocol was presented, which was proved to be Unified Communications (UC) secure. Thus, the presented multi-signature protocol can run safely in multi-protocol executing environments, such as Internet.

Journal of Computer ApplicationsJan 1, 20100 citations

Universally composable signature, certification, and authentication

Ran Canetti

Recently some efforts were made towards capturing the security requirements from digital signature schemes as an ideal functionality within a composable security framework. This modeling of digital signatures potentially has some significant analytical advantages (such as enabling component-wise analysis of complex systems that use signature schemes, as well as symbolic and automatable analysis of such systems). However, it turns out that formulating ideal functionalities that capture the properties expected from signature schemes in a way that is both sound and enjoys the above advantages is not a trivial task. This work has several contributions. We first correct some flaws in the definition of the ideal signature functionality of Canetti, 2001, and subsequent formulations. Next we provide a minimal formalization of "ideal certification authorities" and show how authenticated communication can be obtained using ideal signatures and an ideal certification authority. This is done while guaranteeing full modularity (i.e., each component is analyzed as stand-alone), and in an unconditional and errorless way. This opens the door to symbolic and automated analysis of protocols for these tasks, in a way that is both modular and cryptographically sound.

IEEE Computer Security Foundations Workshop (CSFW)Nov 12, 200484 citations

Universally composable signature, certification, and authentication

Ran Canetti

Recently some efforts were made towards capturing the security requirements from digital signature schemes as an ideal functionality within a composable security framework. This modeling of digital signatures potentially has some significant analytical advantages (such as enabling component-wise analysis of complex systems that use signature schemes, as well as symbolic and automatable analysis of such systems). However, it turns out that formulating ideal functionalities that capture the properties expected from signature schemes in a way that is both sound and enjoys the above advantages is not a trivial task. This work has several contributions. We first correct some flaws in the definition of the ideal signature functionality of Canetti, 2001, and subsequent formulations. Next we provide a minimal formalization of “ideal certification authorities ” and show how authenticated communication can be obtained using ideal signatures and an ideal certification authority. This is done while guaranteeing full modularity (i.e., each component is analyzed as stand-alone), and in an unconditional and errorless way. This opens the door to symbolic and automated analysis of protocols for these tasks, in a way that is both modular and cryptographically sound.

Jun 28, 2004167 citations