Objective:
➢ Understanding the need of data security and integrity to be included during design of distributed operating system.
➢ Types of cryptography modules used by different operating system store data and authorize users.
➢ Implement a file encryption technique using DES for the windows platform.
➢ Comparing the time and space aspects of decrypted file and encrypted file.
ABOUT DES
• The Data Encryption Standard (DES) is a symmetric-key block cipher published by the National Institute of Standards and Technology (NIST).
• DES is an implementation of a Feistel Cipher.
• It uses 16 round Feistel structure.
• The block size is 64-bit.
• Though, key length is 64-bit, DES has an effective key length of 56 bits, since 8 of the 64 bits of the key are not used by the encryption algorithm (function as check bits only).
SCOPE:
• First of all user fulfill the agreement form of this program then user insert a text massage or include text massage file.
• Encryption key as an input as a result, this program will encrypt and decrypt this text massage and save it in a file.
Few Modification has been made from the original project, hope you all like it!