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Joined 2026-09-21 Message
Incoming links: Computer Security examination paper by the University of Oxford (2015)
Past exam of the computer science course of the University of Oxford 2015 Computer security 2026-10-31
Solutions to all three questions of the examination dated 15 June 2015. The cover permits candidates to answer two questions.[ref]
Computer Security examination paper by the University of Oxford (2015). Cover, A12073W1; questions on printed pages 2–7
The authentication claims in Question 2 require particular care: the printed third message permits substitution of Bob's key ticket after his cryptographic nonce becomes public. The solutions distinguish the intended freshness argument from the Dolev-Yao model attack that defeats Bob's authentication. This is a property of the printed protocol, rather than a missing part of the source.