Use this URL to cite or link to this record in EThOS:
Title: Mitigating private key compromise
Author: Yu, Jiangshan
Awarding Body: University of Birmingham
Current Institution: University of Birmingham
Date of Award: 2016
Availability of Full Text:
Access from EThOS:
Access from Institution:
Cryptosystems rely on the assumption that the computer end-points can securely store and use cryptographic keys. Yet, this assumption is rather hard to justify in practice. New software vulnerabilities are discovered every day, and malware is pervasive on mobile devices and desktop PCs. This thesis provides research on how to mitigate private key compromise in three different cases. The first case considers compromised signing keys of certificate authorities in public key infrastructure. To address this problem, we analyse and evaluate existing prominent certificate management systems, and propose a new system called "Distributed and Transparent Key Infrastructure", which is secure even if all service providers collude together. The second case considers the key compromise in secure communication. We develop a simple approach that either guarantees the confidentiality of messages sent to a device even if the device was previously compromised, or allows the user to detect that confidentiality failed. We propose a multi-device messaging protocol that exploits our concept to allow users to detect unauthorised usage of their device keys. The third case considers the key compromise in secret distribution. We develop a self-healing system, which provides a proactive security guarantee: an attacker can learn a secret only if s/he can compromise all servers simultaneously in a short period.
Supervisor: Not available Sponsor: Engineering and Physical Sciences Research Council ; School of Computer Science ; University of Birmingham
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: QA75 Electronic computers. Computer science