User Account

All Pages

Describe how bob can recover the message

Assignment Help Computer Network Security
Reference no: EM13657173

Question 1: Alice and bob agree to communicate privately via e-mail using a scheme based on RC4 but they want to avoid using a new secret key for each transmission. Alice and bob privately agree on 128-bit key k. To encrypt a message m consisting of a string of bits, the following procedure is used.

1. Choose a random 80- bit value v

2. Generate the ciphertext c = RC4(v||k)⊕m

3. Send the bit string(v||c)
a. Suppose Alice uses this procedure to send a message m to Bob. Describe how Bob can recover the message m from (v ll c) using k.
b. If an adversary observes several values (V1 ||C1), (V2, C2).......transmitted be-tween Alice and Bob. how can he or she determine when the same key stream has been used to encrypt two messages?

Question 2:  With the ECB mode. if there is an error in a block of the transmitted ciphertext, only the corresponding plaintext block is affected. However, in the CBC mode, this error propagates. For example. an error in the transmitted C1 (Figure 2.9) obviously cor¬rupts P1 and P2.

a. Are any blocks beyond P2 affected?

b. Suppose that there is a bit error in the source version of P1. Through how many ciphertext blocks is this error propagated? What is the effect at the receiver?

Reference no: EM13657173

Questions Cloud

Profit assembly paint inspection : Profit Assembly Paint Inspection
What is his annual inventory turns : What is his annual inventory turns?
What lens must be used to see clearly an object at infinity : The near point of a certain eye is 100 cm in front of the eye. What lens must be used to see clearly an object 25 cm in front of the eye? The far point of a certain eye is 1 m in front of the eye. What lens must be used to see clearly an object at in..
Minimize the advertising budget : Minimize the advertising budget.
Describe how bob can recover the message : Describe how Bob can recover the message - Through how many ciphertext blocks is this error propagated? What is the effect at the receiver?
The limits of the visible spectrum : The limits of the visible spectrum are about 400 nm to 700 nm. Find the angular breadth of the first order visible spectrum produced by a plane grating having 15,000 lines per inch, when light is incident generally on the grating.(1inch = 2.54 cm)
Decide the angular speed of the wheel : An automobile tire has a radius of 0.380 m, and its center moves forward with a linear speed of v = 18.0 m/s. Decide the angular speed of the wheel.(Assume that there is no slipping of the surfaces in contact during the rolling motion.)
What are some major capacity issues in a hospital? : What are some major capacity issues in a hospital?
What is the ratio of potential energy to kinetic energy : What is the ratio of potential energy to kinetic energy for a comet that has now enough energy to escape from the Sun's gravitational field?

Reviews

Write a Review

Computer Network Security Questions & Answers

  What are service level agreements

What are Service Level Agreements (SLAs) and why are they a critical component of any IT Outsourcing agreements?

  Report of network security

Report of network security solutions around 3 to 4 pages . Example and reasons for evertything thats needed for the sercurity.

  Efficient means of electronic payments

Think about security concerns and limited resources, do you think public sector entities should consider utilizing PayPal to facilitate inexpensive and efficient means of electronic payments?

  Protecting intellectual property rights in software

Explain the reason of each of these approaches and explain how each of them can be used to protect property rights in software. Please include any experiences you have had with these methods.

  Determine public values transmitted for message

Alice and Bob select the numbers 6 and 10 privately. What will be public values they transmit and what would be final secret computed?

  Essence of a digital signature is ensures authentication

1. The essence of a digital signature is that it ensures authentication. Explain how and why it does that.

  Tools to enhance password protection

A report on Tools to enhance Password Protection.

  Boot process for a windows machine

What is the boot process for a Windows machine switches through several different modes. What are they, and how do they impact security?

  Suppose that you are amerchant find out the advantages and

the payment card industry data security standard pci dss is used by credit card companies to ensure the safety of the

  Protocol stack for wap2

WAP protocol, cellular network infrastructure, SSL protect against eavesdropping, network datagrams (packets) be protected at the network layer, pin and fingerprint, Certificate Revocation, Public Key Infrastructure, modern symmetric algorithm bl..

  Design and implementation of a security approach

use Microsoft Powerpoint to create your slides for a 15-minute presentation. It`s about Computer Hacking the same subject that you wrote in the report. You are going to take the same information that you wrote in the report and make it as slides.

  Security and privacy in cloud computing

Prepare a report on the following scenario about security and privacy in cloud computing - Recently increased use of mobile devices and the growth of the Internet in current business practices have led to the provision of Cloud Computing

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

Submit Assignment

Academics

Major Subjects

Majors

Get In Touch

whatsapp: +1-415-670-9521

Phone: +1-415-670-9521

Email: [email protected]

TERMS & POLICIES

HELP & SUPPORT

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd