codetomake.com

Cryptography

2021.03.17 13:45



Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our User Agreement and Privacy Policy .

Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User Agreement for details.

SlideShare Explore Search You Upload Login Signup Home Explore Successfully reported this slideshow. We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime. Cryptography Upcoming SlideShare Loading in … 5 × 1 1 of 22 Like this presentation? Why not share! Share Email Cryptography.ppt by kusum sharma 178079 views cryptography by Abhijeet Singh 22003 views Cryptography by Shivanand Arur 100319 views Introduction to Cryptography by Popescu Petre 6605 views Certification authority by proser tech 3515 views Steganography by Mayank Saxena 19382 views Share SlideShare Facebook Twitter LinkedIn Embed Size (px) Start on Show related SlideShares at end WordPress Shortcode Link

Cryptography

61,512 views
Share Like Download ...

Sidharth Mohapatra

, Student Follow

Published on Sep 19, 2013

Cryptography is the science of using mathematics to encrypt and decrypt data.

Cryptography enables you to store sensitive information or transmit it across insecure networks so that it cannot be read by anyone except the intended recipient.

... Published in: Education , Technology 21 Comments 117 Likes Statistics Notes Full Name Comment goes here. 12 hours ago Delete Reply Block Are you sure you want to Yes No Your message goes here

Login to see the comments

VinayDevdas 2 months ago GovinderN. Verma 3 months ago NasheerAhamed 4 months ago Priyamsingh35 7 months ago PriyamSingh37 7 months ago Show More No Downloads Views Total views 61,512 On SlideShare 0 From Embeds 0 Number of Embeds 314 Actions Shares 0 Downloads 5,921 Comments 21 Likes 117 No notes for slide

Cryptography

1. Presented By : Shibani Sarangi IT Branch, Regd no. 1001289324 Guided By : Prof. X 1 2. 2 Cryptography Vocabulary Encryption & Decryption Transmission Technique Symmetric Cryptography Asymmetric Cryptography 3. 3 Cryptography is the science of using mathematics to encrypt and decrypt data. Cryptography enables you to store sensitive information or transmit it across insecure networks so that it cannot be read by anyone except the intended recipient. 4. 4 Plaintext: Data that can be read and understood without any special measures. Encryption: The method of disguising plaintext in such a way as to hide its substance is called encryption. Cipher text: Encrypting plaintext results in unreadable gibberish called cipher text. Decryption: The process of reverting cipher text to its original plaintext is called decryption. Key: some secret piece of information 5. 5 Cryptanalysis: The art of breaking ciphers, i.e. retrieving the plaintext without knowing the proper key. Cryptographers: People who do cryptography Cryptanalysts: Practitioners of cryptanalysis. Cryptology: The branch of mathematics that studies the mathematical foundations of cryptographic methods. 6. 6 7. 7 For “secret writing” To establish a shared secret when other people (eavesdroppers) are listening. TYPES Mainly classified into two types : 1. Symmetric key cryptography 2. Asymmetric key cryptography 8. 8 encoder decoder (plaintext in - ciphertext out) ciphertextciphertext msgmsg (ciphertext in - plaintext out) (should understand nothingnothing about the msg) eavesdropper bla-blabla-bla cmbcmb--cmbcmb bla-blabla-bla Cipher msg Plain text – in Cipher text - out Should understand NOTHING about the message Cipher text – in Plain text - out 9. Cryptography Symmetric key Asymmetric key cryptography cryptography (Public key cryptography) Classical Modern cryptography cryptography Transposition Substitution Stream Block cipher cipher cipher cipher 9 10. BOTH SHOULD KNOWTHE KEY 10 11. 11 In classical cryptography, a transposition cipher changes one character from the plaintext to another i.e. the order of the characters is changed. 12. 12 Substitution cipher is a method of encryption by which units of plaintext are substituted with ciphertext according to a regular system. 13. 13 A Stream Cipher is a symmetric or secret- key encryption algorithm that encrypts a single bit at a time. With a Stream Cipher, the same plaintext bit or byte will encrypt to a different bit or byte every time it is encrypted. e.g. : Plain text: Pay 100 Binary of plain text: 010111101 (hypothetical) Key: 100101011 ----- Perform XOR ____________________ Cipher text 110010110 ----- 14. 14 Block cipher technique involves encryption of one block of text at a time .Decryption also takes one block of encrypted text at a time. Length of the block is usually 64 or 128 bits. e.g. : Plain text: four and five Four and five Key Key Key wvfa ast wvfa --- 15. 15 Public key cryptography is an asymmetric scheme that uses a Pair of keys for encryption: a Public key, which encrypts data, and a corresponding Private key (secret key) for decryption. 16. 16 Cryptanalysis refers to the study of ciphers, cipher text, or cryptosystems (that is, to secret code systems) with a view to finding weaknesses in them that will permit retrieval of the plain text from the cipher text, without necessarily knowing the key or the algorithm. This is known as breaking the cipher, cipher text, or cryptosystem. Unlike cryptography which is a clearly 17. 17 Known - plain text analysis Chosen – plain text analysis (Differential cryptanalysis) Cipher text - only analysis Man – in – the - middle attack 18. 18 It is a side channel attack which exploits sounds emitted by computers or machines. Modern acoustic cryptanalysis mostly focuses on sounds emitted by computer keyboards and internal computer components Historically it has also been applied to impact printers and electromechanical cipher machines. 19. 19 Use rubber keyboard or virtual keyboards to prevent keystroke sounds. Use acoustic printers. Use Acoustic case for CPU. 20. 20 Cryptography, being an art of encrypting and decrypting confidential information and private messages, should be implemented in the network security to prevent any leakage and threat. It can be done by using any of these techniques discussed above for fortifying the personal data transmission as well as for secure transaction. Acoustic cryptanalysis, being an art of 21. Yang, Sarah (14 September 2005), Researchers recover typed text using audio recording of keystrokes , UC Berkeley News. Adi Shamir & Eran Tromer. Acoustic cryptanalysis . Blavatnik School of Computer Science, Tel Aviv University. Retrieved 1 November 2011. http://en.wikipedia.org/wiki/Cryptography 21 22. 22 Recommended Explore professional development books with Scribd Scribd - Free 30 day trial Cryptography.ppt kusum sharma cryptography Abhijeet Singh Cryptography Shivanand Arur Introduction to Cryptography Popescu Petre Public key cryptography and RSA Shafaan Khaliq Network security and protocols Online Steganography Mayank Saxena Certification authority proser tech Symmetric and asymmetric key Triad Square InfoSec Introduction to Cryptography Bharat Kumar Katur English Español Português Français Deutsch About Dev & API Blog Terms Privacy Copyright Support

×

Share Clipboard

× Facebook Twitter LinkedIn Link

Public clipboards featuring this slide

× No public clipboards found for this slide

Select another clipboard

×

Looks like you’ve clipped this slide to already.

Create a clipboard

You just clipped your first slide!

Clipping is a handy way to collect important slides you want to go back to later. Now customize the name of a clipboard to store your clips.




  • Cryptography Tutorial - Tutorialspoint
    Definition: Cryptography is associated with the process of converting ordinary plain text into unintelligible text and vice-versa. It is a method of storing and transmitting data in a particular form so that only those for whom it is intended can read and process it.
  • Cryptography | Computer science | Computing | Khan Academy
    Cryptography is used in all fields to secure data and prevent it from getting hacked. For example, for securing passwords, authenticating banking transactions, etc. Nowadays, various new cryptographic techniques are developed and cracked; hence, it is important always to be aware of computer threats and take precautions to avoid them as best as we can.
  • What is Cryptography? Definition of Cryptography ...
    Cryptography is the science of using mathematics to encrypt and decrypt data. Cryptography enables you to store sensitive information or transmit it across insecure networks so that it cannot be read by anyone except the intended recipient.
  • Cryptography Techniques | Learn Main Types Of Cryptography ...
    This is called 'decryption.' Cryptography begins when we abandon physical locks and use 'ciphers' instead. Think of [ciphers] as virtual locks. Ciphers allow Alice and Bob to scramble and descramble their messages so that they would appear meaningless if Eve intercepted them. Cryptography has been around for thousands of years.
  • Cryptography - SlideShare
    Cryptography is the study of secure communications techniques that allow only the sender and intended recipient of a message to view its contents. The term is derived from the Greek word kryptos ...
  • cryptography · PyPI
    This tutorial covers the basics of the science of cryptography. It explains how programmers and network professionals can use cryptography to maintain the privacy of computer data. Starting with the origins of cryptography, it moves on to explain cryptosystems, various traditional and modern ciphers, public key encryption, data integration, message authentication, and digital signatures.
  • Real Life Applications of CRYPTOGRAPHY | by Prashanth ...
    Block Cipher. 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. Example: A common block cipher, AES, encrypts 128-bit blocks with a key of predetermined length: 128, 192, or 256 bits.
  • Cryptography and its Types - GeeksforGeeks
    cryptography is a package which provides cryptographic recipes and primitives to Python developers. Our goal is for it to be your “cryptographic standard library”. It supports Python 3.6+ and PyPy3 7.2+. cryptography includes both high level recipes and low level interfaces to common cryptographic algorithms such as symmetric ciphers, message ...
  • What is cryptography? (video) | Cryptography | Khan Academy
    Cryptography is technique of securing information and communications through use of codes so that only those person for whom the information is intended can understand it and process it. Thus preventing unauthorized access to information.
  • What is Cryptography? | Cryptographic Algorithms | Types ...
    Unit: Cryptography. Lessons. Ancient cryptography. Learn. What is cryptography? (Opens a modal) The Caesar cipher (Opens a modal) Caesar Cipher Exploration (Opens a modal) Frequency Fingerprint Exploration (Opens a modal) Polyalphabetic cipher (Opens a modal) Polyalphabetic Exploration (Opens a modal)