Encryption algorithms can be divided into two types according to the type of key: "asymmetric key encryption algorithm" and "symmetric key encryption algorithm". Asymmetric key encryption algorithm refers to an encryption algorithm that uses different keys for encryption and decryption; symmetric key encryption algorithm refers to an encryption algorithm that uses the same key for encryption and decryption.
The operating environment of this tutorial: Windows 7 system, Dell G3 computer.
The basic process of data encryption is to process files or data that were originally plain text according to a certain algorithm, turning it into an unreadable piece of code called "ciphertext", so that it can only be entered when the corresponding password is entered. The original content can be displayed only after the key is obtained. In this way, the purpose of protecting the data from being stolen and read by illegal persons is achieved. The reverse of this process is decryption, the process of converting the encoded information into its original data.
Encryption algorithms can be divided into two types according to the type of key: "asymmetric key encryption algorithm" and "symmetric key encryption algorithm".
The asymmetric encryption algorithm requires two keys: the public key (publickey: referred to as the public key) and the private key (privatekey: referred to as the private key).
The public key and the private key are a pair. If the public key is used to encrypt data, it can only be decrypted with the corresponding private key. Because encryption and decryption use two different keys, this algorithm is called an asymmetric encryption algorithm.
The basic process of asymmetric encryption algorithm to realize the exchange of confidential information is: Party A generates a pair of keys and makes the public key public, and other roles (Party B) who need to send information to Party A use the key (Party A) Party A's public key) encrypts the confidential information before sending it to Party A; Party A then uses its own private key to decrypt the encrypted information.
The opposite is true when Party A wants to reply to Party B. It uses Party B's public key to encrypt the data. Similarly, Party B uses its own private key to decrypt.
The symmetric key encryption algorithm requires only one key: the private key, so it is also called private key encryption. It is an encryption algorithm that uses the same key for encryption and decryption.
Sometimes called traditional cryptographic algorithm, the encryption key can be calculated from the decryption key, and the decryption key can also be calculated from the encryption key. In most symmetric algorithms, the encryption key and decryption key are the same, so this encryption algorithm is also called a secret key algorithm or a single key algorithm.
It requires the sender and receiver to agree on a key before communicating securely.
The security of symmetric algorithms relies on the key. Leaking the key means that anyone can decrypt the messages they send or receive, so the confidentiality of the key is crucial to the security of communication.
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