Design And Construction Of File Encryption System

CHAPTER ONE
INTRODUCTION
There are a number of methods for security measures to be attached to files or documents, these may include file password or file locking, data / file encryption and decryption, installation of antivirus, USB encryption, laptop encryption, firewall, password encryption, database encryption, disk encryption for data etc. Since the use of the computer is so wide and data or file security is very important, an important concept to note is that data or file encryption is one of the best security measures and can be incorporated into systems that participate in data or file transfer and sharing to allow for privacy. This is because it places security measure on the system on the data itself. Applications need to have a way of encrypting data or documents before sending to the recipient(s) at the receiving end, and the recipient should also be able to have a means to decrypt or unlock the encrypted message being sent. This is made possible by using a unique pass code (key or password) for both the encryption and the decryption processes. Encryption is the process of translating plain text data (plaintext) into something that appears to be random and meaningless (cipher text). Decryption is the process of converting cipher text back to plaintext. To encrypt more than a small amount of data, symmetric encryption is used because it renders main security goals which are privacy and authenticity of the communicated data. A symmetric key is used during both the encryption and decryption processes. To decrypt a particular piece of cipher text, the key that was used to encrypt the data must be used.