Useful tips

What is the difference between a digital signature and a message authentication code?

What is the difference between a digital signature and a message authentication code?

Digital signatures are the public key equivalent of private key message authentication codes (MACs). Whereas MACs use private keys to enable a message recipient to verify that a message has not been altered during transmission, signatures use a private/public key pair.

What is the difference between a hash and a digital signature?

A hash is used to only verify the message integrity – if a message changes, the hash of a message will change, too. A digital signature is used to guarantee that a known source generated the message (non-repudiation), and that the message was not altered in transit (integrity).

Is digital signature message authentication?

Digital signatures are the public-key primitives of message authentication. They are used to bind signatory to the message. Similarly, a digital signature is a technique that binds a person/entity to the digital data. This binding can be independently verified by receiver as well as any third party.

Why MAC based authentication Cannot be used as a digital signature?

MAC has a lower length in comparison with the plaintext. Thus, it is not unique like hash function. In other words, two different plaintexts may have the same MAC values. However, the likelihood of this occurrence is very low and thus it can be used for authentication and integrity.

What is the difference between message authentication and entity authentication?

Message authentication (sometimes called data origin authentication) is the assurance that a given entity was the original source of the received data. Entity authentication (or user authentication) is the assurance that a given entity is involved and currently active in a communication session.

What are the different types of the message authentication codes and explain with an example?

These include: FIPS PUB 113 Computer Data Authentication, withdrawn in 2002, defines an algorithm based on DES. FIPS PUB 198-1 The Keyed-Hash Message Authentication Code (HMAC) ISO/IEC 9797-1 Mechanisms using a block cipher.

What is the difference between message integrity and message authentication?

Ensure a message cannot easily be forged. The message digest guarantees the integrity of a message that not been changed. However, message digest does not authenticate the sender of the message. To provide message authentication, sender needs to provide proof that he/she sending the message and not an impostor.

Is MAC a digital signature?

MACs differ from digital signatures as MAC values are both generated and verified using the same secret key. This implies that the sender and receiver of a message must agree on the same key before initiating communications, as is the case with symmetric encryption.

Is digital signature a hash?

The digital signature is basically a one-way hash (or message digest) of the original data that was encrypted with the signer’s private key. To validate the data’s integrity, the recipient first uses the signer’s public key to decrypt the digital signature.

What is digital signature authentication?

A digital signature is an electronic, encrypted stamp of authentication on digital information such as messages. This signature ensures that the information originated from the signer and was not altered, which proves the identity of the organization that created the digital signature.

How is digital signature verified?

When a digital signature is verified, the signature is decrypted using the public key to produce the original hash value. The data that was signed is hashed. If the two hash values match, then the signature has been verified.