Services of digital signature (EDS) provides the company's partners IQusion.

EDS is used by individuals and legal entities as an analogue of a handwritten signature to an electronic document giving legal force equal to the validity of the document on paper, signed the handwritten signature of the authorized person and the seal.

Integration of digital signatures in electronic document management system significantly speeds up the numerous business operations, reducing the amount of paper accounting records, saves staff time and company expenses related to sign an agreement and payment documents, reporting to regulatory authorities, obtaining certificates from various government agencies and other .

Each client generates a unique private and public cryptographic keys EDS.

The private key signature

The private key signature is formed on the basis of absolutely random numbers generated by random number, a public - private key is calculated from EDS in such a way as to get a second from the first was impossible.

The private key signature is a unique character sequence length 264 bits, which is designed for generation of digital signatures in electronic documents. Private key only works in conjunction with a public key. The private key must be kept secret, because anyone who knows him will be able to forge digital signatures.

The document is signed using a digital signature private key, digital signature, which is a single copy only for its owner. This private key corresponds to public key with which you can check whether a signature of its owner.

Public key digital signature and public key certificate

The public key is used to verify digital signature received documents (files). The public key will only work in conjunction with the private key. The public key is contained in the public key certificate, and confirms the public key belonging to a certain person's DS. Besides the public key, public key certificate contains personal information about its owner (name, contact details), a unique registration number, expiration date of Public Key Certificate. With purpose to ensure the integrity of the data presented in the Certificate shall be signed by the private key accredited key certification center. A public key certificate may be published on the site of CA in accordance with the Agreement on the provision of services of EDS.

Signing an electronic document signature

When signing an electronic document to its original content is not changed, and added a block of data, called a digital signature.

Receipt of this unit can be divided into two stages:

1. In the first phase with the software and a special mathematical function is computed so-called "mark messages» (message digest).

This stamp features the following:

• fixed length, regardless of the length of the message;

• a unique fingerprint for each message;

• inability to restore the message to his thumbprint.

If the document has been modified, it will change and his imprint, which will be reflected when checking the digital signature.

2. In the second phase imprint document is encrypted using a software and a private key of the author.

Decrypt a digital signature and retrieve the original print, which will correspond to the document, you can only use the public key certificate of the author.

The calculation of print paper to protect it from unauthorized modifications after signing, and encryption of private key of the author confirms the authorship of the document.

Check EDS received document

Verify digital signatures, the received document is carried out in several stages:

1. In the first stage destination using the software's certificate's public key decrypts the signed print and receives the imprint of the original document.

2. With the help of special software and a mathematical function of the document, which was obtained, is calculated its footprint.

3. When checking the signature compares the original and prints the resulting documents. Result of the test - one of the responses: "true" / "false".

Scheme verify digital signature of the document obtained by software

Electronic digital signature confirms the authenticity and integrity of the document. If it were in the process of delivery made any changes, even very minor, then the replacement is found. A public key certificate contains personal information about the owner, that can uniquely identify the author of the document.

Additional features when working with digital signature

One of additional possibilities when working with EDS is a service of fixing the exact time of the signing of EDS - note the exact time. Mark the exact time accurately determine the time of applying a digital signature, and change later, its value, even the person who left a signature is not possible. May only re-signing with the fixation of modern times. Mark the exact time using the software and hardware complex of CA is synchronized with Coordinated Universal Time (UTC) and is set to within one second.

To send confidential documents via the Internet or local network, it is advisable to use the encryption function. An electronic document is encrypted using the recipient's public key certificate and can only be decrypted private key of the recipient. Consequently, the content of this document can only be read by the person to whom it is addressed.