Digital Signature In Blockchain

In my previous article, we discuseed Hashing in Blockchain. Another use of cryptography in Blockchain is digital signing. 
 
A digital signature of a user is a cryptographically created digital identity of the user. A digital signature is attached to some data during the data transfer mechanism to ensure that the data remains in intact and the original creator of data is identifiable.
 
Digital signatures in a blockchain solves three purposes – authentication, non-repudiation, and data integrity.
  •  Authentication - make sure the message was created by a known sender.
  • Non-repudiation – the sender cannot deny sending the message.
  • Data integrity – the message wasn’t altered in transit.
In this video, speaker explains what a digital signature is, how it works, and how to create digital signatures in your code.
 
 
Digital signatures are commonly used on document signing and document verification. The following diagram shows a document signing and verification process using digital signature.
 
 
 
Source: Wikimedia