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Let us continue with the section of cryptography in this section we will discuss about asymmetric encryption.

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Public key cryptography is the most revolutionary concept in last 400 years in public key cryptography

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that is asymmetric encryption to reader keys.

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Public and private keys are used publicly and be freely distributed.

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While it's very private, key remains a secret.

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The public key is used for encryption and for decryption.

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Private key is used.

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The main difference between these methods is the fact that those symmetric systems used to kill rather

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than one employed by the Semitic schemes.

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One of the keys can be publicly shared, while the other must be kept in private.

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Let us come back to the example of Alice and Bob.

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This time, Alice and Bob don't ever need to meet.

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First, Bob buys a padlock and a matching key.

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Then Bob Mills unlock padlock to Alice and keeping the key safe Alice by the simple lock box that closes

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with the padlock and puts a message in it.

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Then she locks it with Bob Spurlock and mails it to Bob.

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She knows that the mailman can't read the message as he has no way of opening the padlock when Bob receives

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the lock box, he can open it with his key and read the message.

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This only works to send messages in one direction, but Alice could buy a blue lock and the key and

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mail the ballot to Bob so that he can reply.

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Or instead of sending a message in padlock secure lock box, Alice could just send Bob one pair of identical

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keys.

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Then Alice and Bob can send messages back and forth in the Semitic lockbox, as they did in the first

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example.

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Now, I will summarize this real life example.

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Bob generates a keeper consisting of public and private key.

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Bob then publishes this public and Alice it Alice and generates a temporary Semitic.

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And uses Bob's publicly, who securely send it to Bob, Bob then uses his private key to unlock his

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copy of Tricky.

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Bob and Alice can use dosimetry keys to securely send messages back and forth in the next lecture.

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We will see advanced types of asymmetric encryption.