Digital Signature

Digital signature (also called public-key digital signature, electronic signature) is a kind of similar written on paper of ordinary physical signature, but use public-key encryption technology realization, the method used to identify the digital information. A digital signature usually define two complementary operations, one for signatures, another for the verification.
Digital signature does not refer to put your signature scanning into digital images, or use touchpad acquired signature, more not your inscribe.
Digital signature files are easy to verify the integrity of the (don't need QiFeng chapter, QiFeng signature, also do not need the handwriting expert), and digital signature is can't deny sex (don't need handwriting expert to validation).
Say simply, the so-called digital signature is attached to a unit of data on some of the data, or for data unit of password change. This data or transform allows data unit receiver to confirm units of data sources and units of data integrity and the protection of data, to prevent being (such as receiver) were forged. It is to the electronic forms of information on signature of a kind of method, a signature news can in a communications network transmission. Based on public-key cryptosystem and private key cryptosystem can get digital signature, mainly is based on public key cryptosystems digital signature. Including ordinary digital signatures and special digital signature. Ordinary digital signature algorithm has RSA, Shamir, Fiat - ElGamal, Guillou - Quisquarter, Schnorr, Shamir Ong - Schnorr - digital signature algorithm, Des/DSA, elliptic curve digital signature algorithm and finite automaton digital signature algorithm, etc. Special digital signature that have blind signature, proxy signature, group signature, undeniable signature, fair blind signature, threshold signature, with news recovery features signature, etc, it is closely related with the specific application environment. Obviously, the application of digital signature involves legal issues, the federal government based on finite domains discrete logarithm problem set its own digital-signature standard (DSS).
Our Digital technology is asymmetric encryption algorithm of typical application. The application process of digital signature, data sending using their own private key to data validation and or other relevant variables with data content to encrypt data and the completion of the legitimate "signature", data receiver is use the other public key to interpret received "digital signatures", and will interpret results are used to data integrity test to confirm signature legitimacy. Digital signature technology is in network system in virtual environment identified the important technology, can completely replace reality in the process of holograph signs ", in technical and legal is guaranteed. In the digital signature applications, the sender's public key can be easily obtained, but he's private-key requires strictly confidential.
The main function
Ensure the integrity of the information transmission, the sender's identity authentication, prevent transaction in a clean happen.
Digital signature technology is based on the information with sender's private-key is encrypted, together with the original transmitted to the receiver. The receiver only in sending public key can decrypt encrypted information, then use HASH function to receive the original produce a information, and the declassified information contrast. If the same, then explaining the information received is complete, during transmission unmodified, or that the information has been modified so digital signatures can validation information integrity.
Digital signature is a encryption process, digital signature verification is a decryption process.
Personal safety email certificate
With digital signature function of personal safety email certificate is a certificate of a user, refers to the unit used when user email certificate mechanisms ensure safety must have the certificate. Personal safety email certificate is accord with x.509 standard digital security certificate and with digital certificate and S/MIME technology on regular E-mail do encryption and digital signature processing, ensure the safety of the E-mail content, confidentiality, the sender's identity confirmed sex and can't deny sex. With digital signature function of personal safety certificate holder email certificate contains the email address, certificate issued by the holder of the public key, who (CA) and those of the certificate issued by the signature. Personal safety email certificate depends on the realization of the function of user use E-mail system whether to support the corresponding function. At present, MS Outlook, Outlook Express, Foxmail and CA safety E-mail systems are supported corresponding function. The use of personal safety email certificate can be transceiver encryption and digital signature mail, email transmission guarantee the confidentiality, integrity, and undeniable sex, securing E-mail communication parties identity authenticity.