If C is a secure PRG, and D is a secure PRF, is C(m) || D(m) A PRF?
Q: Consider the Hill cipher in which the ciphertext is related to the plaintext using the form: k k2…
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Q: Consider the plaintext PLAINCIPHERTEST, arrange it to 3*5 matrix and rearrange R1 to R3, R2 to R3,…
A: Given plain text is, PLAINCIPHERTEST Arranged in 3*5 matrix Then rearrange R1 to R3, R2 to R3, C1 to…
Q: a) A ciphertext has been generated with an affine cipher, which is defined as follows: C = (a × P +…
A: Answer:- C≡aP+b(mod 26) where; Pis a plaintext letter and Cis the resulting ciphertext letter. To…
Q: a. Describe the steps involved in mounting a statistical attack on a monoalphabetic substitution…
A: Answer (a): Monoalphabetic figure is a substitution figure in which for a given key, the code letter…
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A: Question 5. Monoalphabetic ciphers are stronger than Polyalphabetic ciphers because frequency…
Q: 1) Discuss the security of the following challenge-based scheme for mutual authentication, where…
A: The Needham – Schroeder protocol is one of two important modes of transport intended for use in the…
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A: Introduction: In the DES (Data Encryption Standard) Cipher Block Chaining Mode: It's a cipher mode…
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A: Introduction: In a public key encryption, only one technique is utilised for encryption and related…
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: 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: Let 1 = (Gen1;Enc1;Dec1) and 2 = (Gen2;Enc2;Dec2) be two encryption schemes for which it is known…
A: To identify which is secure 1 0r 2, we need to form a message for 1 As per Encryption Algorithm: m1…
Q: Q1: Based on DES, if the shared key is "SECURITY" and the output of round 15 is "IT*? 7b/" find the…
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Q: In block ciphers, if we use AES for encryption, it does not matter whether the cipher is CBC-based…
A: In block ciphers, if we use AES for encryption, it does not matter whether the cipher is CBC-based…
Q: ce between a hard link and a symbolic (soft) link? Make sure your answers i
A: Hard Link: A hard link is a mirrored replica of the selected file. It makes use of the information…
Q: Consider a large institution that has 9970 employees. How many keys are necessary to allow any pair…
A: Note : As per guidelines we are authorized to answer 1 question when multiple questions are posted.…
Q: "The RSA Algorithm" as a model, apply the RSA algorithm using the following values: p = 3, q = 11, e…
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Q: Consider the final key agreement protocol detailed in the textbook. If Alice and Bob are both…
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Q: Is it possible to encrypt the connection as well as the data from beginning to end? What benefit…
A: Introduction: Link encryption is a type of communication authentication in which all data at both…
Q: What was NIST's initial set of crite for evaluating prospective AES ciphers?
A: AES encryption It is defined as the process of concealing electronic data using an approved…
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A: First Multi-authority secure electronic voting scheme is used. So All Authority can compare the…
Q: odern and a trad
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Q: What is the difference between an ally secure cipher? unconditionally secure cipher and a…
A: Unconditionally secure cipher and Computationally secure cipher are the types of the cipher. The…
Q: Entity A wants to send a message "SECURITY" confidentially to the another entity B using Hill…
A: Given, Message: SECURITY Key = 6 241131610201715 Each alphabet is represented with its equivalent…
Q: Find the ciphertext using DES if the shared key is "SECURITY" and round 15's output is "IT? 7b/"?
A: Public Encryption Key and Shared Key To safeguard communications delivered between strangers, SKIP…
Q: Both cipher feedback mode and cipher block chaining are superior methods for encrypting huge data.…
A: Data Encryption Standard (DES) Cipher Block Chaining Mode: To prevent block replacement, it is a…
Q: Consider a large institution that has 16891 employees. How many keys are necessary to allow any pair…
A: For using symmetric cipher algorithm total pairs of required will beN(N-1)/2 pairs where N is the…
Q: a. Mention the drawback of Mono alphabetic cipher. b. Which Cipher is used to resolve the issue with…
A: Drawback of Mono Alphabetic Cipher: A mono-alphabetic substitution cipher provides a very (too)…
Q: 1. Referring to Figure 15-1, which CAs must B/Y/Z/A/C trust in order to find a path to A/C/Y?
A: Explanation: Steps to reach the node: One can reach the node using following up-links or cross-link…
Q: i) Define “Principle of Integrity”.? Consider any “message” that needs to be secured and explain…
A: Integrity, in the view of computer systems, that will be refers to methods of ensuring data is real,…
Q: Suppose that you receive a digital certificate that contains M and (h(M)]CA, where M = (Alice,…
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Q: With the use of appropriate diagrams, explain the two fundamentally different types of encryption
A: security is a technique to prevent unauthorised access in system. To keep data secret during…
Q: that has 16891 employees. How many keys are necessary to allow any pair of employees to securely…
A: Ans- For using symmetric cipher algorithm total pairs of required will be- N(N-1)/2pairs where N is…
Q: What is "Non-deterministic encryption"? Is one time pad non-deterministic encryption?
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Q: Suppose Alice has a message that she is ready to send to anyone who asks. Thousands of people want…
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Q: Carry out protocol analysis of mutual authentication mechanism over VPN. The protocol analysis must…
A: EXPLANATION: The behavioral form of the data is simply referred to as protocol analysis. It's…
Q: a) Implement Vigenère Cipher to encrypt the following using the Vigenère table. Is there any…
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A: Given the provided letter encoding, what would be the encoding of the plaintext word ATTACKafter…
Q: Let M be the message to be sent by using RSA cryptosystem. If (n, e) is the public key and (n, d) is…
A: Here in this question we have given RSA cryptosystem.and we have asked the expression which is used…
Q: Suppose you observe a CBC ciphertext and two of its blocks happen to be identical.
A: Cipher Block Chaining (CBC) adds a feedback mechanism to a block cipher. The result of the…
Q: Given the following: • Plaintext: HARDWIRED • Key: FUNK • Blocksize: 4 What is the ECB ciphertext? O…
A: Answer : Given Data - Plaintext : HARDWIRED Key : FUNK Blocksize : 4
Q: When both confidentiality and message integrity are provided in Zigbee, what data field/s is/are…
A: ZigBee is a safe wireless communication technology. Its security design compliments the IEEE…
Q: What is the difference between an ally secure cipher? unconditionally secure e cipher and a…
A: what is computationally secure ?? A cipher is known as computationally secure if the amount of…
Q: Consider the encryption function for a symmetric cryptosystem E(k, m) described below, where K = M =…
A: Note: The answer of both subparts along with a straightforward explanation are given in this…
Q: Explain the difference between a secure cipher, a CPA-secure cipher, and a CCA-secure cipher. Under…
A: Difference:- CPA 'CPA' stands for 'Chosen Plaintext Attack.' It means that the attacker can get the…
Q: Each of the following is a true/false statement about a tweakable block cipher (TBC). Place a…
A: Each of the following is a true/false statement about a tweakable block cipher (TBC). Place a…
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- Q: Alice wants to set up a business company that securely deals with her clients. Bob is a potential client that Alice wants to have a good connection. As a security consultant, your job is to devise a plan to establish a secure information exchange. The assumption is made that Alice and Bob already have their public and public keys; (PrivA, PubA) and (PrivB, PubB) respectively, and both of them have exchanged their public key beforehand. Your plan includes comprehensive protocols to secure all messages, according to Alice’s requirements below. Discuss your answers based on Asymmetric Encryption. i) Integrity: Alice and Bob want to make sure that every message sent cannot be forged by anyone. ii) Authenticity: Alice and Bob can verify that messages actually came from them. iii) Confidentiality: Alice exchanges business-related documents with Bob in a way, so that Alice and Bob may open, read or modify the documents.Q: Alice wants to set up a business company that securely deals with her clients. Bob is a potential client that Alice wants to have a good connection. As a security consultant, your job is to devise a plan to establish a secure information exchange. The assumption is made that Alice and Bob already have their public and public keys; (PrivA, PubA) and (PrivB, PubB) respectively, and both of them have exchanged their public key beforehand. Your plan includes comprehensive protocols to secure all messages, according to Alice’s requirements below. Discuss your answers. i) Integrity: Alice and Bob want to make sure that every message sent cannot be forged by anyone. ii) Authenticity: Alice and Bob can verify that messages actually came from them. iii) Confidentiality: Alice exchanges business-related documents with Bob in a way, so that Alice and Bob may open, read or modify the documents.2. Recall the concept of Physically Unclonable Functions, which are an importantcomponent of hardware based security. Here is a simple scenario and simple protocol usingPUFs for authenticating a tag. In the protocol below, the Reader stores ALL possiblecombinations of Challenge-Response pairs for every tag it needs to authenticate. Duringauthentication, the Reader broadcasts the ID of the tag, and a greeting (Gn ). Every tag maysee this message, but only the one with the right ID will process the message. The right tagwith the ID in the message will then feed the greeting to its PUF and compute the responseSn. The response is then sent to the Reader. This should be clear from the Figure below. Forthe next round of authenticating the same Tag, the process repeats with a new Greeting(G n+1 ). Since the Reader has the responses, authentication is straightforward. Recall thatChallenges and Responses are typically 128 or 256 bit strings for RFIDs.From the protocol, and class, it should be…
- A cipher suite is a choice of algorithms for key exchange, authentication and encryption to be used together in TLS. Cipher suites are specified by an abbreviation such as the following: “ADH-DES-CBC-SHA”. Search online and find one example of a cipher suite used in TLS 1.3. Write the name of the cipher suite; then, for each component, write what the abbreviation stands for and for which cryptographic task that algorithm is used in that suite.BOB ALICE Yes Message (m) Hash MD Function Alice public-key Alice private-key Same? Hash Function MD Public-key Decryption Public-key Encryption -MD E Private-Keya MD) + message use the digital signature scheme that is shown in the scenario above as part of the network security protocol suits. But it has two very specific weaknesses that can be solved using the MAC It is very handy and practical t scheme. Explain these 2 weaknesses that can be solved using the MAC scheme.Please answer only in the programming language C++ Implement a known plaintext attack on the hill cipher. Plaintext ="how are you today" and ciphertext ="ZWSENIUSPLJVEU". Deduce the key matrix with dimension = 2. Question 4 Key: [15,12] [11,3]
- A file is encrypted by using an encryption function E and a key k. No other protection checks are made by the file system. If the user wishes to share the file with another user, he makes E and k available to the other user. Compare the above scheme for protecting files with a protection scheme using an access control list, on the basis of i) ease of granting access privileges to users or withdrawing them, and ii) granting different kinds of access privileges to the same file.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 AuthorityBob has designed a secure login system for the student portal of the Xiamen University of Technology (XUT). In Bob's design, a two-factor authentication method is used for verifying the authenticity of the user. A brief description of the design is provided below. For the two-factor authentication, the followings are required: • Factor 1: a user first required to provide a secret password, • Factor 2: the user then needs to provide the correct answer to a security question. To securely store the user password in the system, Bob has used state-of-the-art encryption algorithm, Advanced Encryption Standard (AES), to encrypt the user password and stored the encrypted password in the system database. For securely signing in to the system: the user needs to provide his/her user ID and the corresponding password. This information will be transmitted to the system over a secure communication channel. Upon receiving this information, the system will: o locate/retrieve the corresponding…
- Exercise 2 ( In module 4 we discussed many examples of security protocols using formal notation. For instance, we studied how a dual-factor authentication works when a password generator is used: S → U : N U → P : N, PIN P → U : {N,PIN}K U → S: {N,PIN}K Can you modify the set of rules outlined above to describe the protocol of dual-factor authentication when a mobile device is involved? To receive full credit, please submit 1. a high-level overview of how the protocol would work (e.g. the mobile phone might provide a PIN to the user as opposed to just "clicking" on a button directly on the phone) 2. the description of the protocol using the formal notationSuppose an attacker wants to break a cryptographic scheme - (Gen, Enc, Dec). The attacker kows that for some message m and ciphertext c, it is true that Pr [C=c | M=m] << Pr [C = c). !3! The attacker listens to the channel and sees the ciphertext c. What conclusion can the attacker draw? Note that << means "much less" The scheme has no bias. O The message is probably m. OThe distribution of the messages over the message space is not uniform. The message is probably not m.Public Key Authority is one example of this. Before sending a message to A, the Public Key Authority must prepare a request for B's public key (E(PRauth[PUB] || Request || Time1]). It's debatable whether letter in the alphabet A should be used to understand the message.