[Solved]Q24 Suppose Bob Sender Wants Send Message Alice Sending Message Bob Generates Digital Sign Q37131755

Q2.4
Suppose, Bob (the sender) wants to send a message to Alice. Beforesending the message, Bob generates a digital signature. Assume thatBob and Alice use both of the public-key cryptography system andhash function when computing digital signatures. Say, the hashfunction used to compute and verify signatures is insecure, but thepublic-key cryptography system is secure. Show that Trudy can forgesignatures.

Q2. (Digital Signatures) [2+2+2+1-7 Marks] Suppose Bob and Alice, two business partners, use their smart phones to communicate with each other regarding their business decisions. Hence, their messages are very sensitive and require to be authenticated. Otherwise, an attacker, say one of their business rivals, may perform phone number porting fraud attack. In this attack, the attacker may use another SIM card to port Alice or Bob’s phone number for pretending as Alice or Bob, respectively. Therefore, BoB and Alice uses digital signature scheme in their smart phone to sign messages for ensuring authenticity. The working procedure of the dgital signature is illustrated in FigureQ2. Message Bob’s Siqned Message Signing with private-key Bob (Sender) Verification Verified Message Verification with Bob’s public-key Alice (Receiver) Answer Q2.1, Q2.2 and Q2.3 using the scenario mentioned above. Show transcribed image text Q2. (Digital Signatures) [2+2+2+1-7 Marks] Suppose Bob and Alice, two business partners, use their smart phones to communicate with each other regarding their business decisions. Hence, their messages are very sensitive and require to be authenticated. Otherwise, an attacker, say one of their business rivals, may perform phone number porting fraud attack. In this attack, the attacker may use another SIM card to port Alice or Bob’s phone number for pretending as Alice or Bob, respectively. Therefore, BoB and Alice uses digital signature scheme in their smart phone to sign messages for ensuring authenticity. The working procedure of the dgital signature is illustrated in FigureQ2. Message Bob’s Siqned Message Signing with private-key Bob (Sender) Verification Verified Message Verification with Bob’s public-key Alice (Receiver) Answer Q2.1, Q2.2 and Q2.3 using the scenario mentioned above.

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Answer to Q2.4 Suppose, Bob (the sender) wants to send a message to Alice. Before sending the message, Bob generates a digital sig… . . .