Cryptography - Block cipher & stream cipher

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

1. Block Cipher & Stream Cipher 1

2. Daffodil International University Submitted By Niloy Biswas (171-35-225) Tanvir Islam (171-35-239) Submitted to Ridwanullah Yousuf 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

4. stream cipher Example: 4

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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