Transcript Challenge-response - Prof. Ravi Sandhu

CHALLENGE-RESPONSE
AUTHENTICATION
Prof. Ravi Sandhu
STRONG AUTHENTICATION
CHALLENGE RESPONSE
NETWORK
WORK
STATION
HOST
User ID
Challenge
Response
© Ravi Sandhu
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CHALLENGE RESPONSE
Secret Key
Challenge
Encrypt
Response
© Ravi Sandhu
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CHALLENGE RESPONSE
Secret Key
Challenge
HMAC
Response
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TIME SYNCHRONIZED
NETWORK
WORK
STATION
HOST
User ID
One Time Password
© Ravi Sandhu
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TIME SYNCHRONIZED
Secret Key
Time
HMAC
One Time Password
© Ravi Sandhu
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PUBLIC KEY SIGNATURE
BASED
Private Key
Challenge
Sign
Response=signed(challenge)
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PUBLIC KEY SIGNATURE
BASED
Private Key
Time
Sign
Response=signed(Time)
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PUBLIC KEY ENCRYPTION
BASED
Private Key
Challenge=Encrypt(Response)
Decrypt
Response
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PUBLIC KEY ENCRYPT
BASED
Private Key
Time
Decrypt
verify
Encrypt(Decrypted(Time))
Response=Decrypted(Time)
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