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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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
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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.
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4.  stream cipher
Example:
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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.
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8.  Example of Block Cipher:
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10. Block Cipher VS Stream cipher
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12. If you have any question… please keep it for yourself. I’m not google!
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