1, the number of signatures is different: digital signature is a technology based on public key cryptography. It generates a digital signature by encrypting the document with the sender's private key, and it needs a signer. On the other hand, double digital signature is further strengthened and protected on the basis of digital signature, and it needs two signers.
2. Different encryption keys: The core of digital signature is to use private key for encryption, which ensures the authenticity and non-repudiation of documents. The receiver decrypts the digital signature with the public keys of two signers, and obtains two hash values. By comparing the two hash values, the authenticity, integrity and non-repudiation of the document can be judged. The core of dual digital signature is the need for two signers to sign, which ensures the security and tamper resistance of the document.