The digital signature represents the most efficient means of ensuring the integrity of sent
data (e.g., submitted transactions) and secure verification of their sender.
Therefore, the use of digital signatures is limited to situations where the means of
communication used is a computer (such as
Corporate
Banking or
Internet
Banking).
Digital signature principle
A digital signature is created in the following way: first, a cryptographic check sum is
calculated from the signed data. Based on a private key, the cryptographic check sum is used
to calculate a digital signature.
The verification of the digital signature is similar: the recipient checks that the digital
signature matches the sender's public key. He or she then calculates the cryptographic
check sum of the received data and compares it to the cryptographic check sum received from the
sender. If the check sums match, it has been verified that the data have not been modified since
they were sent by the client.
The recipient has access only to the sender's public key. Only the sender's
public key can be used to verify the sender's digital signature. Anyone can know the public
key. However, the key cannot be used to create a valid digital signature.
