I'm David Llewellyn-Jones and this is my homepage. I'm a researcher in computer security who's also interested in programming and graphics. You might be interested in my research, my software or my random musings.

Want to know more about me? Here's a personality sketch written by a psychologist when I was in school.

“David is of high intelligence, although lacking in true creativity. He has a need for order and clarity, and for neat and tidy systems in which every detail finds its appropriate place. His writing is rather dull and mechanical, occasionally enlivened by somewhat corny puns and by flashes of imagination of the sci-fi type. He has a strong drive for competence. He seems to have little feel and little sympathy for other people and does not enjoy interacting with others. Self-centered, he nonetheless has a deep moral sense.”

Wow. Harsh. But disturbingly accurate.

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26 Apr 2016 : Explicit Delegation using Configurable Cookies #
My slides from the 2016 Security Protocols Workshop are now available to download from the Presentations page. Ross Anderson wrote a brief but neat summary of the presentation on Light Blue Touchpaper, along with the other presentations from the workshop. This is my first publication working on the Pico project (I'll upload the paper once the post-presentation editing stage is complete).
22 Apr 2016 : Easter teaching #
Added Security I for Part 1B students to my teaching page.
15 Mar 2016 : A New Lightweight Homomorphic Encryption Scheme for Mobile Cloud Computing #
Added a further paper to my publications list. This by another of my previous students, Mohd Rizuan Baharon, working on the fascinating area of homomorphic encryption and presented in Liverpool last year.
15 Mar 2016 : On the evaluation of reputation and trust-based schemes in mobile ad hoc networks #
I'm very proud to have worked with Dr Sohail Abbas, one of my previous students, on a paper he published recently "on the evaluation of reputation and trust-based schemes in mobile ad hoc networks". The paper's now up on my publications list.
27 Feb 2016 : Moving to fixed-width after 18 years #
Today I switched the site to a fixed-width template. It wasn't easy, and I wrote a blog post about it so you can share my pain. Click the 'Full width' button on the homepage to go back to how it was before.