Question: Consider the following message authentication code: H: {0, 1}* {0, 1}n H(m) = = m mod k where k is an n-bit secret. (n

Consider the following message authentication code: H: {0, 1}* {0, 1} H(m) = = m mod k where k is an n-bit

Consider the following message authentication code: H: {0, 1}* {0, 1}n H(m) = = m mod k where k is an n-bit secret. (n is say 120 so you can't simply guess k) a. Can you easily forge a MAC tag for some messages? Which messages can you do this for? b. Give the best chosen-message attack that can think of that breaks the MAC (finds the secret key k). Be sure to include the complexity of the attack.

Step by Step Solution

★★★★★

3.50 Rating (150 Votes )

There are 3 Steps involved in it

1 Expert Approved Answer

Step: 1 Unlock

a Can you easily forge a MAC tag for some messages Which messages can you do this for Yesyou can easily forge a MAC tag for any message that is equal to the secret key k mod kFor exampleif the secret ... View full answer

Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock

Step: 3 Unlock

Students Have Also Explored These Related Computer Network Questions!

Describe how the work placement organization monitors and reviews the effectiveness of the services provided to clients in relation to relevant social and cultural factors. Include how this is in...

Planning is one of the most important management functions in any business. A front office managers first step in planning should involve determine the departments goals. Planning also includes...

This data set represents the web server hit logs for a single website for a single day. You're going to do some analysis of the data, but first you need to normalize it properly -- which requires...

A particle is thrown vertically upwards into the air. Its height s (in m) above the ground after time t (in seconds) is given by s = 25t 5t 2 (a) What height does the particle reach? (b)What is its...

TV meteorologists often present maps showing pressure fronts. Such maps display isobarscurves along which the air pressure is constant. Consider the family of isobars shown in the figure. Sketch...

LO.2 Sparrow Corporation would like you to review its employee fringe benefits program with regard to the tax consequences of the plan for the company's president (Polly), who is also the majority...

describe some of the types of approaches which have been applied to the study of work technologies (e.g. humancomputer interaction and work and organizational psychology);

Olive Company is considering a project that is estimated to cost $286,500 and provide annual net cash flows of $57,523 for the next five years. What is the internal rate of return for this project?

4) Use four 16-to-1 multiplexers to implement a 2-bit by 2-bit multiplier. For example, multiplying 2 x 3-6, or in binary 10B x 11B 0110B. (15 marks) S: S: 2 So S1 S: S2

1. First, calculate p, the probability of CHD-1 in each level of BP Status. Take advantage of the fact that the mean of a 0/1 variable is the probability or percentage of observations equaling 1. a....

A police officer randomly selected 585 police records of larceny thefts The accompanying data represent the number of offenses for various types of larceny thefts a Construct a probability model for...

Judging types (J) tend to intermix work and play. Group of answer choices True False

Patrick Corporation acquired 100 percent of O'Brien Company's outstanding common stock on January 1 for $617,000 in cash. O'Brien reported net assets with a carrying amount of $351,000 at that time....

Question two Ever since he was a small boy Nephew has dreamed of owning a car repair business. Following high school, Nephew borrows money from Bankco and enrolls and pays his own way through...

To deal with the continuous disappointing news in the job market, government increased spending. The short-run effect of the policy is ________ a.economic expansion and lower interest rate. b.no...

This house is new and how to set up the network in this house? CLOSET BATH 3 CLOS MASTER BATH SITTING 8'6"X7'0" BALCONY 10'4"x5'8" MASTER WARDROBE MASTER SUITE 18'0"x14'0" UTILITY LIFT DEN...

Help, will thumbs up. tia d full payment was received in cash. Yearly amortization of intangible asset stands at 6M. Given below are the balance sheets as of Dee 31,1979 and Dec 31,1980 as well as...

1. As a general strategy, would you recommend that Carl take an aggressive approach to capacity expansion or more of a wait-and-see approach? 2. Should Carl go with the option for one facility that...

Although new TCP implementations use the SACK option to report the out of order and duplicate range of bytes, explain how old implementations can indicate that the bytes in a received segment are out...

What is the purpose of a firewall?

The DatagramPacket class has two constructors (see Table 25.11). Which constructor can be used as a sending packet? Table 25.11 Some methods in DatagramPacket class public final class...

Tempe Corporation is a calendar-year corporation. At the beginning of 2014, its election to be taxed as an S corporation became effective. Tempe Corp.'s balance sheet at the end of 2013 reflected the...

Farve Inc. recently elected S corporation status. At the time of the election, the company had $10,000 of accumulated earnings and profits, and a net unrealized gain of $1,000,000 associated with...

Alabama Corporation, an S corporation, liquidates this year by distributing a parcel of land to its sole shareholder Mark Ingram. The fair market value of the parcel is $50,000 and its tax basis is...