As an encryption technology, digital signature has the following functions and attributes:

1, to prevent impersonation, others cannot forge the signature of the message, because the private key is only known to the signer, so others cannot forge the correct signature result. Require private key holders to keep their private keys safe.

2. Anti-tampering For digital signatures, the signature and the original file have formed a mixed whole data, which cannot be tampered with, thus ensuring the integrity of the data.

3. Anti-replay in digital signature, if the technology of adding serial number and timestamp to the signature message is adopted, replay attack can be prevented.

Function:

Some methods (such as handwriting, fingerprints, etc. ) has been used to prove the identity of the signer. This is because: the signature is credible; Cannot be forged; Not reusable; Undeniable; The signed document is irrevocable. In the coming digital life, electronic documents will gradually replace paper documents as the main body of information exchange.

The way to prove that the electronic document is made by the author is to make an electronic signature on the electronic document by simulating the ordinary handwritten signature. The author can identify himself by digital signature, and the reader can verify the identity of the author by digital signature. Because the process of information storage, transmission and processing is often carried out on an open communication network.

Therefore, information is more vulnerable to eavesdropping, interception, modification, forgery and replay attacks from outside or inside. Therefore, digital signature should have some special properties to resist these attacks.