A Digital Signature is a form of online encryption that ensures any message sent does not have its contents altered or tampered with during transit. It is the most secure and advanced form of electronic signature available.
When the server digitally signs any information it sends, a one-way hash is added using the public and private key pair. This means that any clients who receive encrypted information from you can decode it using your server’s public key.
If any tampering is made to the information during transit, then the Digital Signature will be altered. If this is the case, you will be alerted to a third-party intercepting and tampering with the information.
How does a Digital Signature work?
A Digital Signature is a numerical value represented as a sequence of characters. These are so complex that only a computer can create and decrypt one.
To break this down into steps, let’s consider James is making payment via a secure online shop and his credit card information needs to be sent to the shop’s server:
- James enters his credit card information through an online shop that is secured by an SSL Certificate.
- Before the information is sent, the credit card details are first encrypted with the Public Key and assigned a Digital Signature.
- Now that James’ card details are encrypted, his information is sent to the online shop’s server for confirmation.
- The server decrypts his details using the connected Private Key which is only located on the server and calculates the Digital Signature of the original message.
- If the received Digital Signature does not match the calculated Digital Signature, then that is confirmation that the information has been tampered with by a third-party during transit.