Encryption and Decryption using Password Based Encryption, MD5, and DES

摘要

Password-Based Encryption gets the encryption key from the password. To make the task from keyword to key is very time-consuming for an attacker, most implementations of Password-based Encryption will be combined with a randomization system, known as salt. It should be that we want to effectively select an encryption key. We may want to encrypt files based on the passwords we enter, so we can remember them. In this case, the only information would be a password. Password-Based Encryption is used in the application because usually the attacker repeatedly tries to guess undetected keywords and is beyond the original sender/recipient control, if the keyword is used to log in to the server, it can detect many possibilities that are not properly done and in the worst case is to shut down the server to prevent more effort, if a tapper take encrypted files that we use. Password Based Encryption with Message Digest (MD5) and Data Encryption Standard (DES) is a cryptographic method using algorithms that combine both hashing and standard encryption methods. MD5 was developed by Ronald Rivest where the MD5 takes messages of any length and generates a 128-bit message digest, and with the use of DES working in plaintext it is useful to return the same size ciphertext.