## 07-02 Secure Computation

• 0:00 - 0:05
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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• 0:57 - 1:02
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,
• 1:05 - 1:10
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,
• 1:19 - 1:21
you'll be able to answer it correctly.
• 1:21 -
Can we achieve this property using cryptography?
Title:
07-02 Secure Computation
Team:
Udacity
Project:
CS387 - Applied Cryptography
Duration:
01:26