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Cryptography - Block cipher & stream cipher

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Niloy Biswas
Niloy Biswas

Here I describe two encryption and decryption method of cryptography. Block Cipher Stream Cipher. Here I described how that method works.

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Daffodil International University SUBMITTED BY NILOY BISWAS (171-35-225) TANVIR ISLAM (171-35-239) Submitted to RidwanullahYousuf Lecturer, Department of SWE Daffodil International University 2 DATE: 01 April 2019
A stream cipher is a symmetric key cipher where each plain text symbol is encrypted one at a time with the corresponding key stream to give a symbol of cipher text stream  stream cipher  How does Stream Cipher work? Unlike block ciphers that operate on chunks of input text, a stream cipher operates on a byte-at-a-time basis using an input stream. Actually, a stream cipher works using two data streams. The second data stream is the stream of key data. The key data stream is generated by a function whose seed is the encryption key. 3
 stream cipher Example: 4
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 Block cipher A block cipher is an encryption method that applies a deterministic algorithm along with a symmetric key to encrypt a block of text, rather than encrypting one bit at a time as in stream ciphers. 7
 Example of Block Cipher: 8
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Block Cipher VS Stream cipher 10
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If you have any question… please keep it for yourself. I’m not google! 12

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Cryptography - Block cipher & stream cipher

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  • 2. Daffodil International University SUBMITTED BY NILOY BISWAS (171-35-225) TANVIR ISLAM (171-35-239) Submitted to RidwanullahYousuf Lecturer, Department of SWE Daffodil International University 2 DATE: 01 April 2019
  • 3. A stream cipher is a symmetric key cipher where each plain text symbol is encrypted one at a time with the corresponding key stream to give a symbol of cipher text stream  stream cipher  How does Stream Cipher work? Unlike block ciphers that operate on chunks of input text, a stream cipher operates on a byte-at-a-time basis using an input stream. Actually, a stream cipher works using two data streams. The second data stream is the stream of key data. The key data stream is generated by a function whose seed is the encryption key. 3
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  • 7.  Block cipher A block cipher is an encryption method that applies a deterministic algorithm along with a symmetric key to encrypt a block of text, rather than encrypting one bit at a time as in stream ciphers. 7
  • 8.  Example of Block Cipher: 8
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  • 10. Block Cipher VS Stream cipher 10
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  • 12. If you have any question… please keep it for yourself. I’m not google! 12