MadeEasy Test Series: Computer Networks - Network Security

Question

Consider the following statements with respect to digital signatures:
S1: Digital signature ensures authenticity of the sender but not integrity of the message.
S2: A single secret key can be used by the sender to sign multiple documents for multiple receiver.
S3: Using a public-key system, the signer signs using his private key and the verifier verifies using his public key.
S4: Both RSA cryptosystem and RSA digital signature scheme uses same set of keys.
Which of the following is true?

Answer 1

Only S3 is correct

Comments

S3

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what is the answer? prove other option wrong if you say s3.

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S1. is False

Digital Signature ensure authenticity of both the sender and integrity of message.

S3. is True. It is just checking authe​​ntication of sender in public key system.

S4. is False. 

RSA Crypto system 

     At sender side - sender uses receiver public key to encrypt plain text.

     At receiver side -  receiver uses its own private key to decrypt the cipher text.

RSA Digital Signature 

     At sender side - sender uses its own private key to encrypt message digest

     At receiver side - receiver uses sender public key to decrypt message digest and verify with the the message digest it calculate.