Reference no: EM133057175

(a) If Bob intends to protect confidentiality of his messages to Charlie using hybrid encryption, he needs to obtain Charlie's public key first. Illustrate the public key infrastructure (PKI) and how Bob should make use of the PKI in this process.

(b) The textbook RSA digital signature is an insecure scheme. As a first step to address the insecurity, the hash-and-sign paradigm is introduced. Illustrate the no-message attack on the textbook RSA digital signature.

Compare the verification algorithm in the textbook RSA digital signature with that in the hash-and-sign paradigm and discuss how the hash-and-sign paradigm solves the no-message attack.

(c) In a peer-to-peer network, an Eclipse attack is where an attacker can control all communications to and from a victim and let the victim view only the version of ledger that the attacker wants the victim to view.Based on your understanding on Bitcoin, examine the security objectives that are affected due to an Eclipse attack.