How asymmetric key cryptography works to achieve Encryption, Integrity and Non-repudiation in data transmission. Which key is used when to achieve what in secure data transmission.

1. Encryption, Integrity and Non-repudiation
Simplified
Mahendra Pratap Singh
MS Cyber Law & Security, Lead Auditor ISO 27001
Team Whitehat People
Email: mpsinghrathore@yahoo.co.in
LinkedIn: www.linkedin.com/in/mpsingrathore
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Website: www.mpsinghrathore.com
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2. Confidentiality
 Symmetric encryption:-
In this encryption, a secret key is shared between both the parties to encrypt and
decrypt message at source and destination respectively.
 Asymmetric encryption:- (aka PKI)
This encryption requires 2 separate keys; one is private and another is public. In
next slides usage of public and private keys is explained by flow chart to achieve
confidentiality, integrity and non-repudiation.

3. Confidentiality
Sender (S) Recipient (R)
Sender encrypts message using
recipient’s Public key at source.
Message is decrypted at destination
using recipient's Private key
01011100100110110

4. Authenticity & Non-repudiation
Sender (S) Recipient (R)
Sender encrypts message using
sender’s Private key at source.
Message is decrypted at destination
using sender’s Public key

5. Integrity: Digital Signature
Message Message Hash Encrypted Hash Hash Algorithm
Digital Signature
Encrypted by private key of signer.
Transmission
Encrypted HashMessage Hash
Decrypted by public key of signer.

6. Integrity: Digital Signature
If decrypted message hash value at destination matches
with second message hash computed at destination,
Integrity is ensured.

7. By
Mahendra Pratap Singh
MS Cyber Law & Security, Lead Auditor ISO 27001
Team Whitehat People
Email: mpsinghrathore@yahoo.co.in
LinkedIn: www.linkedin.com/in/mpsingrathore
Facebook: www.facebook.com/mpsinghrathore1
Website: www.mpsinghrathore.com
Twitter: @mpsinghrathore
Content in slides is best of my understanding with the source.
Thank You