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07-02 Secure Computation

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    So here's the goal of secure computation. Let's suppose Alice and Bob meet at a conference.
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    They don't yet know each other despite the fact that they've been talking to each other
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    through units 1 through 6, but let's pretend they're not quite so friendly yet,
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    and they both have their smart phones.
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    On their smart phone, they have an address book.
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    What they want to do is figure out, do they know any of the same people?
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    This is a pretty common occurrence at conferences.
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    Often, the way people do this is the slow, "Were you ever at this place?"
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    "Do you know someone here?" "Do you know anyone there?"
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    They want to do it more efficiently, so what they'd like to do is have a protocol
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    that allows them to compare their address books and find all the people they know in common.
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    In this case, it would match Dennis since they both know the same Dennis and then they would
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    see the matches but not reveal anything else about their address book to the other person.
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    They want to do this by executing some protocol
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    where at the end of the protocol both parties would know the matching entries
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    but not learn anything else about the other person's address book.
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    More generally, we have two parties - A and B. They have some private information.
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    They want to perform some secure computation,
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    and at the end of that they learn the result of some function on both of their inputs,
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    but they don't learn anything about the other party's input.
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    Now it's time for a question.
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    It's sort of a trick question, but if you were paying attention at the beginning of this unit,
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    you'll be able to answer it correctly.
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    Can we achieve this property using cryptography?
Title:
07-02 Secure Computation
Team:
Udacity
Project:
CS387 - Applied Cryptography
Duration:
01:26
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