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Cryptography is used to secure communication between networked devices.

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In this section I will cover the concepts that are used for cryptography.

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Encryption is used to provide data confidentiality for securing communication between network devices

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without encryption data assent and clear text and can be seen by unauthorized users when data is encrypted

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it is sent as cipher text and needs to be decrypted to be seen as clear readable text with encryption

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keys are used to encrypt and decrypt data.

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One way to use keys for encrypting traffic is with symmetric encryption.

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This type of encryption uses the same key for encryption and decryption some examples of symmetric encryption

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are does three does and a yes another method of using keys to encrypt data is asymmetric encryption

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asymmetric encryption uses different keys for encryption and decryption an example of asymmetric encryption

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would be RSA with encryption there are rules called ciphers the different types of ciphers are substitution

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poly alphabetic and transposition these ciphers just provide different ways to encode data for example

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a substitution cipher substitutes values.

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So ABC and clear text would be encrypted as an LP by simply substituting the letters with different

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ones based on the cipher values hashing provides data integrity to ensure that data has not been modified

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hashing is achieved by generating hash values for data that can be compared if both sides compute the

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same hash value for transfer data.

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Then the data has not been modified.

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If hash values do not match then the data would be considered to be corrupt some hashing methods are

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empty five shall one shot two and H Mac.