What is a digital signature?

A digital signature is based on asymmetric cryptography; it is used to validate that a message is coming from an authentic source and has not changed during transit. Each user has two mathematically linked keys: a private key and a public key. The public key is shared with the receiver, but the private key is kept private. A message encrypted with a private key can only be decrypted using the corresponding public key.

Creation

The data is hashed and then encrypted using the private key. This encrypted hash is the digital signature.

Mechanism

First, the sender creates a public and private key and shares the public key with the receiver. Then, a digital signature is created using the private key. Next, the digital signature is appended to the data to be transmitted. Finally, the receiver decrypts the digital signature using this key. Since the receiver knows that the digital signature, encrypted with the sender’s private key, can only be decrypted with the sender’s public key, the receiver can verify that the message is from an authentic source. The receiver then compares the hashed message (using the hashing algorithm ) and the decrypted message. If the two messages are the same, then it means that the message did not change in transit.

Users

The following are some of the many industries that use digital signatures.

• Healthcare

  Companies working in healthcare are legally required to protect consumer data and, therefore, use digital signatures.

• Financial services

  Companies providing financial services are the prime users of digital signatures as they prioritize data security.

• Manufacturing

  Manufacturing​ companies use digital signatures to speed up the delivery of essential documents while preserving their integrity.