Dr Abubakar-Sadiq Shehu
About
I am a Cyber Security Postdoctoral Research Fellow at the University of Surrey’s DECaDE Centre, where my work focuses on secure digital content provenance, decentralised identity management, and GDPR-compliant trust systems. My research integrates reputation frameworks and privacy-preserving technologies, particularly self-sovereign identity, to build secure digital ecosystems. I hold a PhD in computer science from the University of Porto, Portugal, and have published extensively on topics like secure data delegation and decentralised identity verification.
From 2017–2023, I contributed to the European NanoSTIMA project at INESC TEC Porto, designing GDPR-compliant platforms for secure health data sharing. Prior roles include enhancing Google Search’s NLP algorithms for Sub-Saharan African languages, developing fraud prevention strategies at Apple, and consulting for tech firms on security best practices.
Affiliations and memberships
Research
Publications
Global labour markets face significant disruption from the rapid advance of artificial intelligence (AI) and automation. Digital or gig economy workers, like freelancers and online independent contractors, are more exposed to the disruptive impacts of technological changes due to their flexible working conditions, which often come with flexible contracts, less robust legal agreements and other unstable working conditions. This study explores how gig economy workers benefit from alternative privacy-enhancing decentralised reputation systems and technologies that enable them to manage information like education, certifications, credentials, and professional experience, both by collecting and sharing information with employers. We propose a blockchain framework comprising three components: (1) Self-sovereign identity (SSI) enabling cryptographically secured, portable control over credentials via decentralised storage; (2) Immutable reputation registries leveraging consensus mechanisms to secure tamper-proof work histories; and (3) Privacy-preserving signalling using zero-knowledge proofs (ZKPs) to let workers selectively disclose reputation metrics without revealing sensitive details. We combine Signalling Theory (ST) and the Unified Theory of Acceptance and Use of Technology (UTAUT) to empirically assess real workers' intentions to use this type of decentralised reputation system. Our framework enhances transparency, worker autonomy, and privacy in the digital economy.
Sharing content, including photos, has become effortless thanks to social media and enterprise services. However, these platforms often overlook protecting content owners’ rights, such as proof of ownership, usage rights, and privacy. In this paper, we present a novel SSI application that enables photographers to collect credentials for their photos and assert ownership to third parties in a privacy-preserving manner. We describe a proof-of-concept implementation using the Hyperledger Aries SSI library, which can be extended for real-world deployment. We also discuss the potential for scaling this implementation.