Application overview of Enterprise encryption systems-Introduction to common encryption algorithms

Comments: Common encryption algorithms include symmetric encryption algorithms, asymmetric encryption algorithms, and Hash algorithms. Symmetric encryption is an encryption algorithm that uses the same key for encryption and decryption. The advantage of symmetric encryption algorithms is the high speed of encryption and decryption and the difficulty of using long keys. Assume that two users need to encrypt and exchange data using symmetric encryption, then the user needs at least two common encryption algorithms of the key, which can be divided into three types: symmetric encryption algorithm, asymmetric encryption algorithm and Hash algorithm. Symmetric encryption is an encryption algorithm that uses the same key for encryption and decryption. The advantage of symmetric encryption algorithms is the high speed of encryption and decryption and the difficulty of using long keys. Assume that two users need to use symmetric encryption to encrypt and exchange data, then the user needs at least two keys for exchange and use. If there are n users in the enterprise, the entire enterprise requires a total of n × (n-1) keys. the generation and distribution of keys will become a nightmare for the Enterprise Information Department. The security of symmetric encryption algorithms depends on the storage of encryption keys. However, it is impossible for everyone in the enterprise to keep a secret, generally, they intentionally or unintentionally disclose the key. If a user's key is obtained by an intruder, the hacker can read all the documents encrypted by the user key, if the entire enterprise shares an encryption key, the confidentiality of the entire enterprise document cannot be discussed. Common symmetric encryption algorithms include DES, 3DES, Blowfish, IDEA, RC4, RC5, RC6, and AES. asymmetric encryption algorithms use different keys for encryption and decryption, also known as public/private key encryption. Assume that two users want to encrypt and exchange data, and both parties exchange public keys. One party uses the other party's public key to encrypt the data, and the other party can use its own private key to decrypt the data. If the enterprise has n users, the enterprise needs to generate n pairs of keys and distribute n public keys. Since the public key can be made public, users only need to keep their own private key, so the distribution of encryption keys will become very simple. At the same time, because each user's private key is unique, other users can verify the authenticity of the information source by using the public key of the Information sender, the sender cannot deny that the message has been sent. The disadvantage of asymmetric encryption is that encryption and decryption speed is far slower than symmetric encryption. In some extreme cases, encryption speed is even 1000 times slower than asymmetric encryption. Common asymmetric encryption algorithms include RSA, ECC (for mobile devices), Diffie-Hellman, El Gamal, and DSA (for digital signature) the Hash algorithm is a one-way algorithm. You can use the Hash algorithm to generate a unique Hash value of a specific length for the target information, however, you cannot obtain the target information through the Hash value. Therefore, Hash algorithms are often used in non-recoverable Password Storage and information integrity verification. Common Hash algorithms include MD2, MD4, MD5, HAVAL, and SHA encryption algorithms. Generally, the efficiency of the algorithms can be based on the complexity and length of keys (the longer the key, the safer the key) and encryption/Decryption speed. In the above algorithms, except for the insufficient DES key length and the slow MD2 speed, it has been gradually eliminated. Other algorithms are still used in the current encryption system products.