In the case of PKI (Public Key Infrastructure), A must first make a request to the Public Key Authority, which will then produce and transmit a message to B (E(PRauth[PUB] || Request || Time1]). Which key A should be used to understand the message is controversial.

**Please use the provided information** Shared session key establishment using a Key Distribution Center (KDC). Using the following table, illustrate how Alice can initiate a secure session with Bob with the help of KDC. Here, KEKs are the long term key establishment keys used to transport the session keys across the network securely. Assume the encryption process to be as follows: Divide the key into two halves: LK and RK; Divide the plaintext into two halves: LT and RT; Then ciphertext= LC||RC where LC=LK XOR RT; and RC = RK XOR LT; where LC, RC, LT, and RT are each 4 bits; Plaintext and ciphertext are each 8 bits. For example, if plaintext=A7 (Hexa) and Key = 6D; then LC=6 ⊕ 7 = 0110 ⊕ 0111 = 0001 = 1 (Hexa); and RC = D ⊕ A = 1101 ⊕ 1010 = 0111 = 7 (Hexa); so Ciphertext = 17 (Hexa). To decryptt, it does the reverse operation: Given ciphertext of C=LC||RC, it finds plaintext T=LT||RT, by finding LT=RC ⊕ RK and RT = LC ⊕ LK. In the above example, LT = 7 ⊕D = 0111⊕1101=1010=A; RT=1 ⊕…

When it comes to PKI (Public Key Infrastructure) In order to get B's public key, A must first submit a request to the Public Key Authority, which will then generate and send a message to B (E(PRauth[PUB] || Request || Time1]). It's debatable which key A should use to interpret the message.

Please refer to the following for the locking procedure: After an item has been unlocked, a higher-numbered item can no longer be locked. Any moment is appropriate to open locks. Only X-locks are used for this purpose. Demonstrate how the protocol does not ensure the serialisation of the data.