Write pseudocode for the password guessing algorithm, Computer Network Security

Assignment Help:

Write Pseudocode for the password guessing algorithm:

Consider the following authentication protocol:

Client

Transmission

Host

Explanation

U, user

U à

 

I am user U

 

ß {n, DES, SHA-1}

n, random challenge, DES, SHA-1

- I have SHA_1(P(U)), where P(U) is password of user U

 

- Here is a random challenge n, please use DES and SHA-1 to generate a response

r=DES(n, SHA-1(P))

U, rà

 

Response r is the encryption of the hash of the password P of user U using key n, DES for encryption, and SHA-1 for hashing.

 

 

ß yes/no

Compare: DES-1(n, r) to SHA_1(P(U))

Can the password of user U be obtained by using an offline password guessing attack? If your answer is yes, describe the attack and write pseudocode for the password guessing algorithm.  If your answer is no, describe why the protocol is resistant to an offline guessing attack.

2) Using RSA, perform an encryption then a decryption of the message M=5 using p=3, q=11, and e=7. (please add explanation, Show all your work, not just the final answer.)

3) You are the designer of a password security policy that requires passwords to expire once they have a probability of 0.001 of being guessed.  A potential attacker can test 1,000,000 passwords per second. If you chose passwords to be alphanumeric ("A" through "Z", "a" through "z", and "0" through "9"), what would you have to set the maximum lifetime of a password to in order to meet the required guessing probability (represent in days)?Assume the password size is 9 characters.


Related Discussions:- Write pseudocode for the password guessing algorithm

Explain authentication process in a synchronous token system, Question: ...

Question: (a) Explain briefly the PCI Control Objectives which enterprises must meet to be compliant with the Payment Card Industry Data Security Standard (PCI DSS). Specify a

Public key cryptosystem based on rsa technology, Problem: (a) What is ...

Problem: (a) What is the minimum length of a password that could be considered to be "strong" in the context of today's computing power? (b) The security of a PIN system,

Describe the functionality of a router, QUESTION: (a) Explain, with the...

QUESTION: (a) Explain, with the aid of a diagram, a Star topology of a network of your choice. (b) Illustrate on the use of a MAN and give an example of one. (c) Describe

Calculate the minimum sampling rate, QUESTION An analog sensor is used...

QUESTION An analog sensor is used to monitor the temperature of sea water at different depth. The sensor is fitted to a buoy and incorporates a wireless transmitter that send

What is the major security flaw of set, QUESTION (a) Discuss why it is ...

QUESTION (a) Discuss why it is considered more secure to use the SET (Secure Electronic Transaction) for e-commerce instead of using SSL (b) Describe how the dual signature

Bus topology, BUS TOPOLOGY In a bus topology all devices are attached ...

BUS TOPOLOGY In a bus topology all devices are attached to a single long cable and any device can send data to any other device. For this function, coordination is needed to d

Ip address, How to find an ip address?

How to find an ip address?

Discuss five alternative testing techniques, QUESTION Testing of a Busi...

QUESTION Testing of a Business Continuity Plan (BCP) does not need to be costly or to interrupt the daily operations of the business. The result of the test should also be look

Explain the various costs of quality, Problem 1: Show what are the bene...

Problem 1: Show what are the benefits of project quality management? • Customer satisfaction • Reduced cost • Increased competitiveness • Fulfilment of social and economic r

Semester 2, Do you have assignment solutions for CCE UPES MBA for oil and g...

Do you have assignment solutions for CCE UPES MBA for oil and gas semester 2

Write Your Message!

Captcha
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!

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