Solution-Message authentication code

Message authentication code

Assignment Help Basic Computer Science

Reference no: EM133294884

Question 1. Explain, using an example, how the adversary can modify the seventh bit of a ciphertext generated using a block cipher (e.g., AES) in CBC mode in such a way that the change in the corresponding message is small and easily predictable by the adversary. (The adversary has no access to the decryption key.)

Question 2. How can a message authentication code (MAC) be used to determine the au- thenticity of a message? (Show (1) which steps the sender and receiver follow, (2) what is transmitted, and (3) why these steps guarantee message authen- ticity.)

Question 3. Explain how a ciphertext generated using the substitution cipher can be decrypted without knowing the decryption key.

Question 4. Before HMAC was proposed, it was quite common to use MACk(m) = H(k||m) where H is a collision-resistant hash function. Show that this is not a secure MAC when H is constructed via the Merkle-Damga ¨rd transform.

Reference no: EM133294884

Questions Cloud

Boolean function : In the truth table of a Boolean function with five inputs, how many rows would you expect to see, not counting the header row?

Define the parsing in natural language processing : Define the Parsing in natural language processing, Logic translations in Oz, Logic translations in Prolog.

How would you sell instant coffee via bundles : MKT 130 Oral Roberts University How would you sell Instant Coffee VIA Bundles and still maintain customer value? What would be specifically included

Compose a marketing communications plan : Compose a marketing communications plan or an 'advertising plan': simply focus on exactly what the brief asks you to do, do not over-elaborate

Message authentication code : How can a message authentication code (MAC) be used to determine the au- thenticity of a message?

Create countries that have adopted euro currency experience : What problems does the use of this currency create when the countries that have adopted the euro currency experience asymmetric business cycles?

Given class tree and child class fruittree : Given a class Tree and a child class FruitTree, and given the statement below

Identify customer experience and customer experience value : Explain customer experience. Identify customer experience and customer experience value practices, and best practice recommendations you have for any brand

Examine the buying decisions involved in this situation : BUSINESS 101 University of Oxford Discuss the likely buying situation the university is faced with for the purchase of the new ERP system. Examine the buying

User Account

All Pages

Message authentication code

Reference no: EM133294884

Reference no: EM133294884

Questions Cloud

Reviews

Write a Review

Basic Computer Science Questions & Answers

Identifies the cost of computer

Input devices

Cores on computer systems

Prepare an annual budget in an excel spreadsheet

Write a research paper in relation to a software design

Describe the forest, domain, ou, and trust configuration

Construct a truth table for the boolean expression

Evaluate the cost of materials

The marie simulator

What is the main advantage of using master pages

Describe the three fundamental models of distributed systems

Distinguish between caching and buffering

Assured A++ Grade

Academics

Major Subjects

Majors

Get In Touch

TERMS & POLICIES

HELP & SUPPORT