Show a situation that the above algorithm is vulnerable to the man/women-in-the-middle attack.
Q: Alice and Bob use the ElGamal scheme with a common prime q=131 and a primitive root a=6. Let Bob's…
A:
Q: Alice and Bob use the ElGamal scheme with a common prime q= 131 and a primitive root a=6. Let Bob's…
A: Key generation Common prime q=131 primary root = 6 Bob's public key =3 Random integer chosen k= 4…
Q: Alice and Bob use the ElGamal scheme with a common prime q=131 and a primitive root a=6. Let Bob's…
A: Given, YB=3, q=131, a= 6, k=4, M= 9 The formulas use are : C1=ak mod qC2 = KM mod qK = YBk mod q
Q: Question 1 : a) Generate the public private key pairs for Bob using the following values Bob P = 19…
A: RSA algorithm: Choose 2 large prime numbers P and Q Calculate n=P×Q Select a public key or…
Q: Alice and Bob use the ElGamal scheme with a common prime q= 131 and a primitive root a = 6. Let…
A: Answer Step1: Key generation Common prime q=131 primary root αα = 6 Bob's public key YBYB = 3 Random…
Q: Question 5 a) Roger wants to send Simon a message asking him to transfer RM6,000 to his account.…
A:
Q: In RSA, suppose p = 3, q = 11, e = 7, and d = 3. Given the message m = 5, show the encryption…
A: RSA : RSA is a public key cryptographic algorithm or asymmetric key encryption technique that uses…
Q: If e = 241015, employ the low-exponent attack to determine d. please do it by hand and take care to…
A: Tо соmрute the vаlue fоr d, use the Extended Euсlideаn Аlgоrithm tо саlсulаte…
Q: tocol. a. Given p = 13, g = 4, SA = 4, and SB = 5. Compute TA, TB, and the shared key k using…
A: prime number p = 13 primitive root α = 4 A's private key SA = 4 A's public key bis taken TA =…
Q: 6. Consider the failed attempt of Alice to get Bob’s public key as shown in the following figure.…
A: Please find the answer to the above question below:
Q: Consider an encryption system in which the entropy of a plaintext is 32 bits per 128 bit block and…
A: Unicity distance is defined as U=H(K)/(lg Σ -H(X))where H(K) is the entropy of the key, and for…
Q: The following diagram describes a secure communication between a sender and a receiver; answer the…
A: From the data given in the diagram, it is clear that the scheme used for encryption is Asymmetric…
Q: Consider the final key agreement protocol detailed in the textbook. If Alice and Bob are both…
A: if both Alice and Bob are honest and any adversaries are passive, then the components given below…
Q: Consider the following mode of block cipher operation: C₁ = Ex(C-1) @P for i>I Ex(IV) Pi C₁ H where…
A: The given formula for Encryption is as follows: Ci = EK(Ci - 1)⊕Pi for i > 1 If i = 1, then the…
Q: State the attack scenario (e.g. ciphertext-only, known-plaintext, chosen-plaintext,…
A: Ciphertext is nothing but an encryption algorithm that transforms an original message into secret…
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A: one of the main attack, public key encryption is vulnerable is Brute-force attack. Brute force…
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Q: 8.9. Suppose you observe a CBC ciphertext and two of its blocks happen to be identical. What can you…
A: The answer is
Q: Question 1. Understand the following problem scenarios and draw their structural diagrams.…
A: Answer : The required solution for the above given question is mention as below,
Q: 3. Suppose that Alice and Bob are using the right shift cipher (M,C, e, d, K) to commu- nicate…
A: Given: Suppose that Alice and Bob are using the right shift cipher (M,C,e,d, K) to commu- nicate…
Q: (a) Suppose you are given an ElGamal encryption of an unknown plaintext M ∈G. Show how to construct…
A: Answer is given below-
Q: Alice and Bob use the ElGamal scheme with a common prime q=131 and a primitive root a=6. Let Bob's…
A: Key generation Common prime q=131 primary root = 6 Bob's public key =3 Random integer chosen k= 4…
Q: B. If Alice uses the same k to encrypt two messages M₁ and M₂ as (12, 65) and (12, 64), what is the…
A: The answer is
Q: Given the following table describing the procedure for Alice to send a signed message with RSA…
A: Answer :
Q: Question 9: Using public key cryptography, X adds a digital signature ø to message M, encrypts , and…
A: The question has been answered in step2
Q: Alice and Bob use the ElGamal scheme with a common prime q= 131 and a primitive root a = 6. Let…
A: Below is the answer to above question. I hope this will meet your requirement...
Q: Explain how the adversary can modify a ciphertext generated using a block cipher (e.g., AES) in CBC…
A: Answer: We have answer in handwritten format . I will attached in next step in brief details. how…
Q: For reasons, that will become clear, the version of RSA encryption covered in the lecture is called…
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Q: Consider the following encryption scheme for a block cipher (using the notation frequently used in…
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Q: Alice and Bob use the ElGamal scheme with a common prime q=131 and a primitive root a=6. Let Bob's…
A: Your answer is given below:
Q: 7. Alice wants to communicate with Bob, using public-key cryptography. She establishes a connection…
A: please see the next step for solution
Q: Suppose a public-key cryptosystem encrypts integers (say, modulo another integer n). Show that if…
A:
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Q: ) Assume that users Alice & Bob wish to compute shared session key using Diffie- Hellman key…
A:
Q: Alice and Bob use the ElGamal scheme with a common prime q= 131 and a primitive root a = 6. Let…
A: Solution is given below:
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A: Here i am using caesar cipher :…
Q: Alice and Bob use the ElGamal scheme with a common prime q=131 and a primitive root a=6. Let Bob's…
A: Key generation Common prime q=131 primary root = 6 Bob's public key =3 Random integer chosen k=…
Q: Suppose we have the encoding that enables Carol to mount the cube root attack (see The Cube Root…
A:
Q: Alice and Bob use the ElGamal scheme with a common prime q= 131 and a primitive root a = 6. Let…
A: Common prime q=131 primary root α = 6 Bob's public key YB =3 Random integer chosen k= 4 Plane text M…
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Q: Consider an encryption system in which the entropy of a plaintext is 32 bits per 128 bit block and…
A: Unicity distance is characterized as U=H(K)/(lg Σ - H(X)) where H(K) is the entropy of the key,…
Q: A Man-in-the-Middle attack can be successfully performed on the Diffie-Hellman key exchange protocol…
A: Man in the middle attack The attacker need to establish a secret with the party that starts the key…
1)
a) Given that Bob has an RSA key pair (PU, PK), where PU is his public key and PK is the private key, design an
b) Show a situation that the above algorithm is vulnerable to the man/women-in-the-middle attack.
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- Suppose that Alice and Bob communicate using ElGamal cipher and f (p. 9. Z) is common public values. Bob generates his private key d ER Z and then computes the corresponding and public public key y=g" (mod p). To save time, Bob uses the same number r each time he encrypts a plaintext message m (ie., r is a fixed nonce of Bob, and it is not randomly generated each time encryption is performed). Assume that Alice compute the ciphertext for the message m as (cc) = (g mod p, mxy mod p). and for the message m as (1,2)=(g" mod p, xy' mod p). Show how an adversary who possesses a plaintext-ciphertext pair (m. (c.ca)) can decrypt (1, 2) without knowing the private key d of Bob.Design a cryptographic solution for implementing the dinning cryptographers protocol. You should consider the following: The secret messages shared between any two agents in the protocol are communicated over public channels only. The announcements made by each agent must be traceable in a trustworthy way to that agent. Your solution should be a new protocol that addresses the above two requirements.1. Assume user A and B are communicating with each other. They are in need to verify the integrity of the message using hash function. User A encrypts only the hash code that was generated by him and sends it to user B. Show how could this be done and communication happen. 2. Now user A has decided to provide confidentiality along with the services offered in Question 1. Illustrate the scenario in all the possible ways. 3. Alice and Bob need to share a secret key for further communication. Show how the key can be shared using symmetric and asymmetric pattern. 4. Show the key distribution scheme in which there is high chance of man-in-the-middle attack with suitable illustrations. 5. Explain what a nonce is and the reason for using a nonce. Discuss how certificates are obtained from certificate authority and the certificates are exchanged between the user.
- Suppose that you receive a digital certificate that contains M and (h(M)]CA, where M = (Alice, Alice's public key) and "CA" is Certificate Authority. Assuming that you trust the CA, after verifying the signature on the certificate, what do you then know about the identity of the sender of the certificate? Remember that: [Xleob indicates encryption via Bob's private key to X (signature) h(X) indicates the cryptographic hash function applied to X O The sender is Alice O The sender is Trudy I cannot deduce the identity of the sender from the certificate The sender is the Certificate Authority3. Alice publishes her RSA public key: modulus n = 27455269 and exponent e = 191. (a) Bob wants to send Alice the message m = 27453912. What ciphertext does Bob send to Alice? (b) Alice knows that her modulus factors into a product of two primes, one of which is p = 5011. Find a decryption exponent d for Alice. (c) Alice receives the ciphertext c= 5329179 from Bob. Decrypt the message.Alice and Bob has designed an RSA algorithm based on n = 152416431947009. Bob chooses the public key eB = 11. (a) Find the private key dB of Bob so that 0 < dB. Justify each step. (b) What should Alice do to send the message 123456789 to Bob? What message Bob receives? (c) What should Bob do to decrypt the message he receives from Alice? Please solve all part
- Network Security problem Q1] Consider the RSA encryption algorithm. Suppose that a malicious user intercepts the ciphertext C = 18 that is being sent to Alice. If Alice's public key PUa = {5,35) is known by the malicious user, show how the malicious user will recover the plaintext M? [Hint: find M=?] Note: C stands for Ciphertext, M stands for Message (Plaintext), PUa stand for Alice's public key.Alice sets up an RSA public/private key, but instead of using two primes, she chooses three primes p, q, and r and she uses n=pqr as her RSA-style modulus. She chooses an encryption exponent e and calculates a decryption exponent d. Encryption and Decryption are defined: C ≡ me mod n and m ≡ Cd mod n where C is the ciphertext corresponding to the message m. Decryption: de ≡ 1 mod φ(n) | Let p = 5, q = 7, r = 3, e = 11, and the decryption exponent d = -13. n = 105 & φ(n) = 48 Q: Alice upgrades to three primes that are each 200 digits long. How many digits does n have?Consider an RSA key set for Alice with p = 23, q = 17, n = 391 and e = 15.a) Her public key is (e, n) = (15, 391). Is her private key (d, n) = (47, 391)? JusVfy your answer. b) Suppose Bob wants to encrypt a message 90 for Alice using RSA keys for confidenVality. Whatis the corresponding cipher text?Justify your answer.
- Can anyone please explain to me why we have such equations below in part b) and c)? They are the solutions to the questions, but I can't really understand why and how to get that. Many thanks. ==== QUESTION ==== In the Shamir secret sharing scheme, we distribute a secret among q different users as follows. If our secret is a message (m1, . . . , mk) from V (k, q) then, we encode it as a codeword of the Reed-Solomon RSk(q) and give one coordinate to each user. In this problem, we will use q = 7, k = 4 and the parity check matrix H4 below for RS4(7). H4 = [1 1 1 1 1 1 1, 0 1 2 3 4 5 6, 0 1 4 2 2 4 1] a) Write a generator matrix for RS4(7) b) A new secret is selected and user #1 receives share value 0, user #2 receives share value 6 and user #3 receives share value 1 and are collaborating to discover the new secret. Explain why they can’t recover the secret with only this information. c) Now, suppose users #1, #2 and #3 (as in the previous item) discover, in addition to the values of…Consider an RSA key set for Alice with p = 23, q = 17, n = 391 and e = 15.a) Her public key is (e, n) = (15, 391). Is her private key (d, n) = (47, 391)? Justffy your answer. b) Suppose Bob wants to encrypt a message 90 for Alice using RSA keys for confidenVality. Whatis the corresponding cipher text?Justify your answer.8. A security system is used to encrypt the password of a cryptocurrency wallet (crypto wallet) and generate 10 different codes that the owner of the wallet can copy on 10 papers that he will hide with great care. So if a thief finds 1 of these hidden papers, he will not be able to unlock the wallet. Indeed it would be necessary to have at least 6 (any 6) codes to reconstitute the secret passphrase and unlock the wallet. How is it possible ?