Digital signature What is it and how does it work

Until not long ago, the only way to demonstrate the authenticity of a document was with a handwritten signature or an official seal. Today times are changing and the rise of the Internet and new technologies have led to the appearance of the digital signature.

What is digital signature
In Spain, the electronic signature is regulat by Law 59/2003 on Electronic Signatures, which in article 3.1 defines it as follows:

The electronic signature is the set of data in electronic form. Record together with others or associat with them, that can be us as a means of identification of the signatory.

Likewise, it recognizes two types of electronic signature.

Unequivocally identifies the signatory

Advanc electronic signature: allows the signer to be identifi and any subsequent changes to the sign data to be detect, which is uniquely link to the telephone list signer and the data to which it refers and which has been creat by means that the signer can maintain under his or her exclusive control.
Recogniz electronic signature: It is an advanc electronic signature bas on a recogniz certificate and generat using a secure signature creation device. For legal purposes it is the only equivalent to a handwritten signature.
The functions of the electronic signature are three:

It ensures the integrity of the sign document, meaning that it has not suffered any alteration or manipulation.
This type of signature was creat thinking about operations carri out over the Internet.

How the digital signature works

The digital signature of a document is obtained after an operation in three steps:

A mathematical algorithm is applied to the document to create a fingerprint call a hash. This hash is a number that uniquely identifies the document.
The Hash is encrypt using the signer’s private key.
To verify the authenticity of the document, the recipient must have a program that supports digital signatures. The program uses the public key to decrypt the hash key. This way you can compare the calculat hash with BO Leads the decrypt hash. If they match, the document has not been modifi.

Our Clinic Cloud program offers the option to sign documents electronically in two modalities: verifi signature with legal support and unverifi signature. You have more information on this support page.

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