Basic Principles and differences between digital signature and Encryption

Comments: What are the basic principles of Digital Signature and encryption? The digital signature mainly goes through the following processes: information senders use a one-way HASH function to generate information summaries; information senders use their own private key signature information summaries; the information sender sends the information together with the signed information digest. What are the basic principles and differences between the information signature and encryption?

The digital signature mainly goes through the following processes:

Information senders use a one-way HASH function to generate information summaries;

Information senders use their own private key signature information abstract;

The information sender sends the information together with the signed summary;

The information recipient generates a new information digest for the received information by using the same one-way HASH function as the information sender, then, use the public key of the Information sender to verify the information digest to check whether the identity and information of the Information sender have been modified.

Digital Encryption mainly goes through the following processes:

When a message sender needs to send information, a symmetric key is generated to encrypt the message to be sent;

The information sender encrypts the above symmetric key with the public key of the information receiver;

The information sender combines the result of step 1 and Step 2 to the information recipient, which is called a digital envelope;

The information recipient uses its own private key to decrypt the encrypted symmetric key, and uses this symmetric key to decrypt the ciphertext encrypted by the sender to obtain the real original text.

Although both digital signatures and digital encryption use public key systems, the implementation process is the opposite, and the key pairs used are different. The digital signature uses the sender's key pair. The sender encrypts the key with its own private key, and the receiver decrypts the key with the public key of the sender. This is a one-to-many relationship, anyone with the sender's public key can verify the correctness of the digital signature. Digital encryption uses the accesskey pair of the receiver, which is a many-to-one relationship. Anyone who knows the accesskey of the receiver can send encrypted information to the receiver, only one person with the private key of the recipient can decrypt the information. In addition, the digital signature only uses asymmetric key encryption algorithms, which can ensure the integrity, identity authentication and non-repudiation of the sent information, digital encryption uses a combination of symmetric key encryption algorithms and asymmetric key encryption algorithms to ensure the confidentiality of sent information.