An electronic signature is a digital signature for sure but all digital signatures need not be electronics signature. A digital signature is a broader term and is used to encrypt messages, software, financial documents and all that can be tampered with. It is easy to forge a handwritten signature or stamp but same is not true with an electronic signature.
A digital signature provides a validation and security layer to the messages that are sent over public channels. A digital signature uses cryptography system that employs both public as well as private keys. A public key is used to encrypt the data whereas a private key is used for decryption.
A sender encrypts the electronics document with a recipient’s public key and sends it. When it reaches a recipient, a private key that is known to the owner of the message is used to decrypt it. So unless there is a pairing of private keys, the data always remain in non-readable form.
How Digital Signature works
A user needs a private key and an encryption software to put a digital signature on an electronic file. A digital stamp that is placed on the document is difficult to tamper with. A user will promptly come to know if anyone tries to forge the document that is secured with a digital signature.
In the first step, the characters of the document are shortened to a fixed value key by a process called hashing. This process makes the data retrieval faster due to shorter hashed key. The final document after hashing is called message direct.
The software then encrypts this message direct with the owner or user’s private key to create a digital signature.
Finally, the software adds this digital signature to the hashed document.
Now let us see what happens when this document reaches the recipient.
As soon as the other user receives the document, the software at the recipient’s system decrypts the digital signature with sender’s public key and converts it back to message digest.
Now the software needs to make sure that the data is not forged during transmission. To do this, the software hashes the document to create a message direct. If this message-direct matches the message-direct created during decryption process, then it means the document is original and is not tempered with.
Use Digital Signatures to Transmit Documents Safely
Businesses are relying heavily on using digital signatures on all the sensitive data. Electronics signature is one example of the same and is being used extensively across the world by business houses and SMBs. Digital signature is endorsed by not only private and public enterprises but also by government organizations on a large scale. I hope you got the introduction to digital signature and how it works. Do share your queries, if any, in comments section.