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07-16 Putting It All Together

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    Now, we have the last thing that we needed to complete the Garbled Circuit Protocol,
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    the way Bob obtains his inputs is using oblivious transfer.
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    That could be done at this stage to enable Bob to learn his inputs to the circuit.
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    Alice sends the garbled circuit along with her inputs and Bob can evaluate the circuit.
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    Then from the encrypted output wires, Bob can obtain the result of the circuit execution,
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    and he could share that with Alice or they could flip roles and do it again.
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    And then Alice would obtain the output.
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    We have one little step in this protocol that we haven't described yet,
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    which is how you actually obtain that output value.
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    The outputs for the garbled tables are all encrypted,
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    so at the end of the execution what Bob has is a list of encrypted wire labels.
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    He wants to turn that into semantic output. That's left as the question for the exam.
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    I should note that actually executing protocols like this, doing all these encryption is really expensive.
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    This works for any function, but it is very expensive.
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    It's a very active research area, how to do this faster.
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    This is one of the things my research group works on as well as a lots of other researchers
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    to try to find ways to provide properties like the one described here
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    but without as much computation effort as executing the protocol that I have just described.
Title:
07-16 Putting It All Together
Team:
Udacity
Project:
CS387 - Applied Cryptography
Duration:
01:14
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