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DTTF/NB479: Dszquphsbqiz Day 34. Announcements: Today: digital cash Thursday will be workday for presentations. Anyone needing help can meet me in my office. Friday: presentations Elliptic curves Quantum cryptography Questions?. Digital Cash: goals. Electronic: want speed and security
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DTTF/NB479: Dszquphsbqiz Day 34 • Announcements: • Today: digital cash • Thursday will be workday for presentations. Anyone needing help can meet me in my office. • Friday: presentations • Elliptic curves • Quantum cryptography • Questions?
Digital Cash: goals • Electronic: want speed and security • Can’t be counterfeited • Anonymous: spender’s ID not disclosed to merchant • Payment done offline • Transferable • Divisible (can make change) Okimoto and Ohta: Universal electronic cash, In Proc. Advances in Computing – CRYPTO, 1991
Digital Cash Exercise • T&W 11.1 summarizes a system statsfying goals 1-4 (can’t give coins away, a single denomination only) • Focus is on preventing fraud due to double-spending • Adds lots of complexity • Interpret this as “adds lots of equations” • Handout • Read/skim the 3-page summary of chapter. • Do the questions alone or with a partner. • Submit at end of class