Challenge Response Authentication by Azaharul Islam Asik

2. My topics is Challenge
Response Authentication

3. Topics to be covered
• Definition
• Ways of Authentication
• Summery of the topics

4. Definition
The claimant proves that she knows a secret
without revealing it.

5. Ways of Authentication
• Using a Symmetric-Key Cipher
• Using Keyed-Hash Functions
• Using an Asymmetric-Key Cipher
• Using Digital Signature

6. Using a Symmetric-Key Cipher
These also happened in two stages
i. authentication using a nonce
ii. authentication using a timestamp.

7. Fig: Challenge response authentication using a nonce
Using a nonce

8. Fig: Challenge-response authentication using a timestamp.
Using a timestamp

9. Using Keyed-Hash Functions
Fig: Challenge-response using a keyed-hash function

10. There are two advantages to this scheme
i. Encryption/decryption algorithm is not
exportable to some countries.
ii. We can preserve the integrity of challenge and
response messages

11. Using an Asymmetric-Key Cipher
Fig: Challenge-response using an Asymmetric-Key Cipher

12. Using Digital Signature
Fig: Challenge-response using Digital Signature.

13. Remember these again
• Ways of Challenge Response
Authentication

14. Any Questions?
justianasik@gmail.com

15. Thanks for being
with Me