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Symmetric Encryption Algorithm AES provides:

Confidentiality (Yes and it is very obvious)

Authenticity (I think yes but some blogs say no, assuming only the parties communicating, have the shared key and the fact that the message is successfully decrypted means that it is encrypted by another person. If your answer is no, can you explain?)

Integrity (Not able to decrypt does not mean that someone cannot flip bits in the encrypted message and alter output of decryption, AES is susceptible, if yes, can you point me to an example?)

Asymmetric Encryption Algorithm RSA provides:

Confidentiality (Yes and it is very obvious)

Authenticity (encrypt with private key and decrypt with public key)

Integrity (Not able to decrypt does not mean that you cannot flip bits in the encrypted message and alter out of decryption, RSA is susceptible, if yes, possible can you point me to an example?)

Generic questions

  1. For argument's sake, in signing, assuming the size of message getting signed is within the limits of key size and comparing original message with decrypted-signed message is easy, hashing is still required? If yes, is this because someone can send an [altered message + corresponding signed message without decrypting the message] if not hashed and hashing makes this really hard to do?

  2. For argument's sake, to achieve integrity, can I hash and encrypt with a symmetric key and use this to check bulk data integrity?

  3. HMAC is faster because there is no encryption involved and hence used to check bulk data integrity?

  4. Difference between MAC and HMAC correct? I am confused because MAC also has hashing involved. HMAC has double hash?

MAC enter image description here

HMAC enter image description here

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    $\begingroup$ As it is stated, this post contains about 10 questions, most of which have already been answered here. Please focus on one item at a time and check for previous questions / answers first. Note that AES is a block cipher, and RSA by itself is just a primitive. As such, neither provides any security by it's own, they need a secure mode of operation to act as a cipher, such as AES-EAX, or RSA-OAEP. In general, RSA signature generation is not the same as RSA encryption $\endgroup$
    – Maarten Bodewes
    Sep 20 at 1:18

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