Pronunciation sh ù Zi Qi ā n mí ng Cu ò w ò
brief introduction
This kind of data or transformation allows the receiver of the data unit to confirm the source and integrity of the data unit, and protects the data from being forged by people (such as the receiver). This is a method of signing an electronic message, and the signed message can be transmitted in a communication network. Digital signature can be obtained based on both public key cryptosystem and private key cryptosystem. At present, digital signature is mainly based on public key cryptosystem. Include general digital signature and special digital signature.
Ordinary digital signature
There are RSA, ElGamal, Fiat-Shamir, Guillou- Quisquarter, Schnorr, Ong-Schnorr-Shamir digital signature algorithms, Des/DSA, elliptic curve digital signature algorithms and finite automata digital signature algorithms. Special digital signatures include blind signature, proxy signature, group signature, undeniable signature, fair blind signature, threshold signature, signature with message recovery function and so on. It is closely related to the specific application environment. Obviously, the application of digital signature involves legal issues, and the federal government of the United States has formulated its own digital signature standard based on the discrete logarithm problem over a finite field.
digital signature
Technology is a typical application of asymmetric encryption algorithm. The application process of digital signature is that the sender of the data source encrypts the data checksum or other variables related to the data content with his own private key to complete the legal "signature" of the data, and the receiver of the data interprets the received "digital signature" with the public key of the other party, and uses the interpretation result to check the integrity of the data to confirm the legality of the signature. Digital signature technology is an important technology to confirm identity in the virtual environment of network system, which can completely replace the "autograph" in the real process and get technical and legal protection. In the management of public and private keys, the application of digital signature is just the opposite of PGP technology for encrypting emails. In the application of digital signature, the sender's public key is easy to obtain, but his private key needs to be kept strictly confidential.
function
Ensure the integrity of information transmission, the identity authentication of the sender, and prevent denial in the transaction.
Digital signature technology encrypts abstract information with the sender's private key and sends it to the receiver together with the original text. The receiver can decrypt the encrypted digest information with only the transmitted public key, and then use a hash function to generate digest information for the received original text and compare it with the decrypted digest information. If they are the same, it means that the received information is complete and has not been modified during transmission, otherwise it means that the information has been modified, so the digital signature can verify the integrity of the information.
Digital signature is an encryption process and digital signature verification is a decryption process.