[SOLVED] please answer the following questions of computer security.I need the original answer.
Im stuck on a Computer Science question and need an explanation.
Exercise 14.1 Cryptographic protocols are intended to let agents communicate securely over an insecure network. Is this statement correct?
Exercise 14.2 Cryptography needs physical security. To what extent is this statement correct?
Exercise 14.6 Consider the RSA signature algorithm without a hash function, i.e.s=me mod n. Explain how, and to what extent, an attacker could forge signatures if there are no redundancy checks on the message m.
Exercise 14.7 When a document is too long to be processed directly by a digital signature algorithm, a hash of the document is computed and then signed. Which properties do you require from this hash function to prevent an attacker from forging signatures?
Distinguish between situations where the attacker only knows messages signed by the victim and situations where the attacker can choose messages the victim will sign.
Distinguish between selective forgeries, where the attacker has control over the content of the forged message, and existential forgeries, where the attacker has no control over the content of the forged message.
Consider the specifific requirements of hash functions used with an invertible signature algorithm such as RSA.