Mathematical representation. Cryptography 1. 1 SUBSTITUTION TECHNIQUES . INTRODUCTION the practice and study of techniques for constructing and analyzing protocols that overcome the influence of adversaries and which are related to various aspects in information such as data confidentiality data integrity and authentication Applications of cryptography include ATM cards, computer passwords, and electronic commerce We equated cryptography with a toolkit where various cryptographic techniques are considered as the basic tools. It is now considered as a ‘broken’ block cipher, due primarily to its small key size. A substitution cipher is a type of encryption where characters or units of text are replaced by others in order to encrypt a text sequence. Cryptographic Techniques: Plain Text and Cipher Text, Substitution Techniques, Transposition Techniques, Encryption and Decryption, Symmetric and Asymmetric Key Cryptography, Steganography, Key Range and Key Size, Possible Types of Attacks. Some Resources Cryptography Seminar And Ppt With Pdf Report. In cryptography, a substitution cipher is a method of encrypting in which units of plaintext are replaced with ciphertext, according to a fixed system; the "units" may be single letters (the most common), pairs of letters, triplets of letters, mixtures of the above, and so forth.The receiver deciphers the text by performing the inverse substitution. Substitution ciphers are symmetrical encryption techniques, but modern symmetric encryption can be much more complicated. It is still a respected block ciphers but inefficient compared to the new faster block ciphers available. SUBSTITUTION TECHNIQUES. In the second chapter, we discussed the fundamentals of modern cryptography. Of course, even the strongest substitution code wouldn’t stand up to five minutes of intense hacking using today’s technology. Digital Encryption Standard (DES) − The popular block cipher of the 1990s. Note: Special case of Substitution cipher is known as Caesar cipher where the key is taken as 3. These two methods are the basic building blocks of the encryption techniques and can also be used together, which is called a product cipher. One of these tools is the Symmetric Key Encryption where the key used for encryption and decryption is … In this section and the next, we examine a sampling of what might be called classical encryption techniques. But though these techniques are in no way secure enough for modern applications, they did pave the way for the development of contemporary methods of encryption and cryptographic analysis. A substitution technique is one in which the letters of plaintext are replaced by other letters or by numbers or symbols. CLASSICAL ENCRYPTION TECHNIQUES . Substitution Techniques. Cryptography Seminar and PPT with pdf report Sumit Thakur January 10, 2015 Cryptography Seminar and PPT with pdf report 2017-02-10T05:58:43+00:00 CSE Seminars 7 Comments Cryptography Seminar and PPT with pdf report: Cryptography is the practice and the study of concealing the information and it furnishes … Symmetrical encryption is a type of encryption that is used for the encryption and decryption of electronic data by just one key (a secret key). Substitution technique and transposition technique are the fundamental methods of codifying the plaintext message to acquire the respective ciphertext. Substitution ciphers are a part of early cryptography, predating the evolution of computers, and are now relatively obsolete. There are two basic building blocks of all encryption techniques: substitution and transposition. A study of these techniques enables us to illustrate the basic approaches to symmetric encryption used today and the types of … The encryption can be represented using modular arithmetic by first transforming the letters into numbers, according to the scheme, A = 0, B = 1,…, Z = 25. 2.2. A study of these techniques enables us to illustrate the basic approaches to symmetric encryption used today and the types of … Triple DES − It is a variant scheme based on repeated DES applications. In this section and the next, we examine a sampling of what might be called classical encryption techniques.