Signing with the Qualified Electronic Signature (QES)
How exactly is an electronic signature verified?
According to the Public Key Certificate, the signature verification reveals the information about the owner of the certificate (signatory): last name, first name and patronymic, validity of the certificate, contact information, etc.
What is the function of the QES, which the document is signed with?
- Identify the author of the signature (full name, natural or legal person, Tax Infividual Number or USREOU (code of the Unified State Register of Enterprises and Organizations of Ukraine);
- Determine whether the document has changed since it was signed;
- Protect the document from forgery;
- Record a timestamp, which is a very important parameter for an electronic document, as it allows you to confirm the authenticity of the signature even after the certificate has expired, or it has been withdrawn or revoked.
What is a timestamp?
The timestamp is a signed with QES document by which the Timestamp Service certifies that it has been assigned a hash function from the document at the specified time. The value of the hash function is also indicated in the label. It certifies, for example, that the signature was created before the signature key certificate was revoked. Thus, to verify the signature created before the certificate is revoked, you can use a certificate that has already been revoked.