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Digital Signature

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Digital signature

  • A digital signature is an electronic, encrypted, stamp of authentication on digital information such as email messages or electronic documents. 
  • A signature confirms that the information originated from the signer and has not been altered. 
  • It provides the highest levels of security and universal acceptance. 

Working of Digital Signature

Sender’s side 

  • When the sender electronically signs a document two keys are generated: Public and Private. 
  • The private key is kept by the signer and it should be kept securely. On the other hand, the receiver must have the public key to decrypt the message. 
  • Then the Hash function is used on the document to create Hash, which is also known as digest. 
  • Then the private key is used to encrypt hash. 
  • The document is sent to the recipients along with the sender's public key. 

Receiver’s side

  • The recipient receives the document and decrypts the encrypted hash with the sender's public key certificate. 
  • A cryptographic hash is again generated on the recipient's end using the same hash function that the sender used. 
  • Both cryptographic hashes(of sender and receiver) are compared to check its authenticity. 
  • If they match, the document hasn't been tampered with and is considered valid. 


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