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TOR Extended 3 - Applied Cryptography

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    And the correct answer is the second and third options.
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    The first one is not true. Alice can determine the key using
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    the typical Diffie-Hellman protocol as discussed in the Unit 3
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    by taking the value G to the power Y and raising
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    it to the power X. The fourth option is not true; adding the
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    hash to the message actually increases the size of it.
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    To see whether second and third options are true, let’s take
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    a look at what could happen without including the hash.
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    So Alice picks the value X, calculates G of X and
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    encrypts G of X with Bob’s public key. She then tries to send
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    this to Bob. Now, you could intercept the message, then
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    send a different value to Bob, Bob recalculate the key,
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    G of X prime Y. Bob would then send G of Y which Mallory
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    could intercept and send a new value to Alice.
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    Alice would then calculate a non-sense key and have no
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    idea that the key she has calculated is worthless. Adding the
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    hash value of the key to this protocol allows Alice to verify
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    that she has a valid key that came from Bob and not
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    from some attacker in the middle.
タイトル:
TOR Extended 3 - Applied Cryptography
Video Language:
English
Team:
Udacity
プロジェクト:
CS387 - Applied Cryptography
Duration:
01:01
Udacity Robot edited 英語(米国) subtitles for TOR Extended 3 - Applied Cryptography
podsinprint_user1 edited 英語(米国) subtitles for TOR Extended 3 - Applied Cryptography
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English subtitles

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