describe the simple protocol for classical cryptographic key exchange. assume alice and bob want to communicate and cathy is the trusted third party
Simple protocol for Classical Cryptographic key exchange
Goal
Alice and bob want to communicate
Criteria
Cathy is the trusted third party
Classical Cryptographic key exchange
How do Alice and Bob begin?
Consider trusted third party, Cathy
Use this to exchange shared key KS
Simple Key Exchange Protocol
describe the simple protocol for classical cryptographic key exchange. assume alice and bob want to communicate...
5. Diffie-Hellman key exchange. Alice and Bob use Diffie-Hellman key exchange protocol to communicate in secret. They publicly announce a prime number p = 23 and a primitive root r = 5 under modulus 23, Alice picks a secret key a-6 and in turn receive the key ß-19 from Bob (a.) (2 points) What is the key that Alice sends to Bob? b) (2 points) What is the shared secret key?
Question1: Alice and Bob use the Diffie–Hellman key exchange technique with a common prime q = 1 5 7 and a primitive root a = 5. a. If Alice has a private key XA = 15, find her public key YA. b. If Bob has a private key XB = 27, find his public key YB. c. What is the shared secret key between Alice and Bob? Question2: Alice and Bob use the Diffie-Hellman key exchange technique with a common...
Answer all of it asap Discrete mathematics Problem 10 (10 pts) Alice and Bob would like to exchange a key using the Diffie-Hellman protocol that uses the following public information: the cyclic group Zio, and 5 as its base element. Alice: If she chooses 3 as her private key, which element does she send to Bob. Bob: If he chooses 4 as his private key, which element does he send to Alice Key-Exchanged: What is their Private Key exchanged. Problem...
If Alice and Bob are using quantum key distribution with light polarization and the BB84 protocol, given the information below, write the resulting key Alice and Bob use in the blank ⟷ = 0 ↕︎ = 1 ⤡ = 0 ⤢ = 1 Alice sends: ⤢ ↕︎ ↔︎ ⤢ ↕︎ ↕︎ ⤢ ↔︎ ↔︎ ⤡ ↕︎ ⤡ Bob uses filters: ╳ + + + ╳ + ╳ ╳ + + ╳ ╳ The key they agree on is
Diffie-Hellman Key Exchange: Alice and Bob wants to agree on a key. First, both agree on p = 23 and g = 5 which is public. Alice chooses her secret key xA = 8 and Bob xB = 14. (a) What will be the shared secret key? (b) DH Key exchange is vulnerable to the following attack. Adversary sits between Alice and Bob, intercepting all messages. Alice and Bob thinks they talk to each other while in fact both talking...
ints) Suppose Alice and Bob want to communicate using the elliptio e on the modulo p= 23 and the curve Ep: y26a+7 (mod 23). Bob chooses a point Q= (16, on the curve an integer k Recoverthene sm essage. a pair of points (Yİ.Y5) where Y1 = (4,7) and ½ = (12,6). Recover Alic from Alice ger K-1. He hecemessage. (12,6). Recover then receives from Alice ints) Suppose Alice and Bob want to communicate using the elliptio e on the...
The Diffie-Hellman key exchange is vulnerable to the following type of attack. An opponent Carol intercepts Alice’s public value and sends her own public value to Bob. When Bob transmits his public value, Carol substitutes it with her own and sends it to Alice. After this exchange, Carol simply decrypts any messages sent out by Alice or Bob, and then reads and possibly modifies them before re-encrypting with the appropriate key and transmitting them to the other party. Choose all...
Authentication Protocol: 3 Marks] Q4 (Authentication Protocol) The following mutual authentication protocol is proposed based on a symmetric-key cryptography algorithm. We assume that the cryptography algorithm that is used here is secure. Given that the following protocol does not provide mutual authentication. Give two different attack scenarios where Trudy can convince Bob that she is Alice. Briefly explain each attack scenario performed by Trudy with proper diagram which on the protocol. "Alice",R E(R, KAB E(R+1, KAB) Alice Bob [Hints: You...
Suppose that Alice wants to initiate a message exchange (also called session) to instruct her bank, NetBank, to pay Bob N40. Alice shares a long-term secret, X, with NetBank (hereafter denoted as C). Alice starts the session by sending a service request, (A, C, n), to NetBank, 3. a. where A is Alice's identity, C is NetBank's identity, and n is a nonce. Assume that NetBank keeps a record of the nonces used by Alice for X. Answer the following...
The Diffie-Hellman key exchange is vulnerable to the following type of attack. An opponent Carol intercepts Alice’s public value and sends her own public value to Bob. When Bob transmits his public value, Carol substitutes it with her own and sends it to Alice. After this exchange, Carol simply decrypts any messages sent out by Alice or Bob, and then reads and possibly modifies them before re-encrypting with the appropriate key and transmitting them to the other party. Choose all...