Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Computer Engineering Expert

1. Alice and Bob are sending a message m to each other

a) Give one method to attain confidentiality for m.

b) Give one method to attain integrity but NOT confidentiality for m

2. Computer B needs a user name and password for every login. User A requires to log on over the Internet. One solution is to send in the user name and the password in clear text.

a) What is the security vulnerability of this solution?

b) Design a better solution. Draw the diagram only to describe message exchange and content of each message.

3. A stream cipher is used to encrypt. The plain text m1 is 10101010, the pseudo random k is: 01101011

a) What is the cipher text c1? (Demonstrate the whole mathematical steps)

b) If another plain text m2 11100010 is encrypted with the same pseudo random number k andgenerate cipher text c2, what useful information about m1 and m2 can you extract from c1 and c2? (Demonstrate the entire mathematical steps)

4. B receives a financial transaction request message m from someone claims to be A. The message is encrypted with a shared security key k which only A and B know. Suppose the encryption is absolutely unbreakable.

a) Can B be reasonably sure that message is generated by A? Why?

b) If B shows another person C that B could use the key k to decrypt the message, could C be reasonably sure that message is generated by A? Whey?

c) Design a different protocol so that when B receives a message m from the real A, both B and C could be reasonably sure that the message is indeed generated by A?

5. If the time to encrypt a message m using a 64-bit secret key k algorithm is T, use the big-O notation to answer the following problems:

a) How to decrypt the message with brutal force? What is the amount of time required?

b) If length of the key is doubled, what is the amount of time needed to decrypt message with brutal force? Why?

6. With CBC encryption, message blocks m1-m2-m3-m4 are encrypted into c1-c2-c3-c4. Now if a hacker intercepts cipher text and retransmits c1-c3-c3-c4, what would be the “plain text” blocks being decrypted into? (Demonstrate all detail calculations)

Computer Engineering, Engineering

  • Category:- Computer Engineering
  • Reference No.:- M91996

Have any Question? 


Related Questions in Computer Engineering

1 discuss the differences between a firewall and a packet

1. Discuss the differences between a firewall and a packet filter. 2. Give reasons why firewalls do not give total security. 3. Discuss the advantages of using an application-level firewall over a network level firewall. ...

In an ipv4 datagram the value of total-length field is

In an IPv4 datagram, the value of total-length field is (00A0) 16 and the value of the header-length (HLEN) is (5) 16 . How many bytes of payload are being carried by the datagram? What is the efficiency (ratio of the pa ...

Question 1value analysis is carried out ata the conceptual

Question 1 Value Analysis is carried out at: a. the conceptual stage b. production stage c. product maturity stage d. product decline stage Question 2 Required capacity is a function of technology. True False Question 3 ...

Standards are very important part of industry benchmarks

Standards are very important part of industry benchmarks, regulations, and quality systems.  Explain the following in details: The purpose and need of standards.  Give at least three example List at least three sets of U ...

1 a source socket address is a combination of an ip address

1. A source socket address is a combination of an IP address and a port number. Explain what each section identifies. 2. Explain how a client process finds the IP address and the port number to be inserted in a remote so ...

1 list the possible values of c and d for an implementation

1. List the possible values of C and D for an implementation that ensures both consistency assumptions on page 470. 2. List at least one more possible pair of values for C and D if such assumptions are not maintained. 3. ...

Discussionthe benefits of microsoft officebullidentify at

Discussion "The Benefits of Microsoft Office" • Identify at least two ways that a user can combine content from two or more Office applications. Explain the major benefits of doing so for each identified example. • Descr ...

In the segregation model the agents look to their

In the Segregation model, the agents look to their neighborhood composition to decide if they are happy. Can you make the size of shape of the neighborhood a parameter? How does this change the results of the model?

1 what system is the father of almost all modern multiuser

1. What system is the father of almost all modern multiuser systems? 2. Which paper is the foundation of all subsequent studies of computer security? 3. Why is the top-down approach to information security superior to th ...

In the second lab we use ftp to transfer some files we use

In the second lab, we use FTP to transfer some files. We use Wireshark to capture some packets. We show that FTP uses two separate connections: a control connection and a data-transfer connection. The data connection is ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen