Record Details

Constructing Provably Secure Identity-Based Signature Schemes

Electronic Theses of Indian Institute of Science

View Archive Info
 
 
Field Value
 
Title Constructing Provably Secure Identity-Based Signature Schemes
 
Creator Chethan Kamath, H
 
Subject Identity Based Signature
Provably Secure sSgnatures
Schnorr Signature
Oracle Replay Attack
Galindo-Garcia Identity Based Signature
Random Oracles
Identity-Based Cryptosystems
Identity Based Signatures - Forking
Provable Security
Selective-Identity Model
Computer Science
 
Description An identity-based cryptosystem (IBC) is a public-key system where the public key can be represented by any arbitrary string such as an e-mail address. The notion was introduced by Shamir with the primary goal of simplifying certificate management. An identity-based signature(IBS) is the identity-based counter part of a digital signature.
In the first (and primary) part of the work, we take a closer look at an IBS due to Galindo and Garcia–GG-IBS, for short. GG-IBS is derived through a simple and elegant concatenation of two Schnorr signatures and, importantly, does not rely on pairing. The security is established through two algorithms (both of) which use the Multiple-Forking(MF) Algorithm to reduce the problem of computing the discrete logarithm to breaking the IBS. Our focus is on the security argument : It turns out that the argument is flawed and, as a remedy, we sketch a new security argument. However, the resulting security bound is still quite loose, chiefly due to the usage of the MF Algorithm. We explore possible avenues for improving this bound and , to this end, introduce two notions pertaining to random oracles termed dependency and independency. Incorporating (in) dependency allows us to launch the nested replay attack far more effectively than in the MF Algorithm leading to a cleaner,(significantly) tighter security argument for GG-IBS, completing the final piece of the GG-IBS jigsaw.
The second part of the work pertains to the notion of selective-identity (sID) for IBCs. The focus is on the problem of constructing a fully-secure IBS given an sID-secure IBS without using random oracles and with reasonable security degradation.
 
Contributor Chatterjee, Sanjit
 
Date 2018-04-03T16:43:40Z
2018-04-03T16:43:40Z
2018-04-03
2013
 
Type Thesis
 
Identifier http://etd.iisc.ernet.in/2005/3330
http://etd.iisc.ernet.in/abstracts/4194/G25722-Abs.pdf
 
Language en_US
 
Relation G25722