Cryptogaphy

1. SEMINAR REPORT ON
CRYPTOGAPHY
SUBMITTED TO:
Mr.SANJAY SINGH & Mr. S. K. SHAH
SUBMITTED BY:
Mustahid ali

2. TOPICS COVERED IN THE
SEMINAR :
• BASIC DEFINATIONS OF TERMS USED
IN CRYPTOGRAPHY
• NEED OF CRYPTOGRAPHY
• TYPES OF CRYPTOGRAPY
• APPLICATIONS

3. BASIC DEFINATIONS
• Encryption: process of coding the
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message.
Decryption: decoding the message in
original form.
Cipher text: encrypted data.
Key: single piece of private information.
Plain text: original information.

4. INTRODUCTION:
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Cryptology=kryptos+logos
Which means hidden +words
Important services that cryptography
provides
• 1.secrecy
• 2.authencity
• 3.integrity

6. NEED OF CRYPTOGRAPHY:
• It is necessary when communicating over
untrusted medium.
• To increase the privacy & security.
• Protection against theft & alteration

7. TYPES :
Cryptography
Single key
Or
Secret key
Two key
Or
Public key
Hash function

8. Single key :
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One key is used by sender & receiver
Key is transferred by a secure medium.
Provides secrecy & authenticity.
Major disadvantage is transfer of key
because it is costly, inconvenient & slow

9. Two key :
• Uses two keys.
• employs two keys that are mathematically
related.
• Both the keys are required for decryption.
• It provides integrity along with privacy &
authenticity.

10. Hash functions :
• are algorithms that, in some sense, use no
key. Instead, a fixed-length hash value is
computed based upon the plaintext that
makes it impossible for either the contents
or length of the plaintext to be recovered.
Hash algorithms.
• Provide a measure of integrity.

11. Applications:
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Atm cards.
Computer passwords.
Electronic commerce.