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

Issue-specific security policy (issp), Issue-Specific Security Policy (ISSP...

Issue-Specific Security Policy (ISSP) The ISSP addresses specific areas of technology, needs frequent updates and having statement on organization’s position on a particular iss

Categories of controls-information security, Categories of Controls Cont...

Categories of Controls Controlling risk through mitigation, avoidance or transference is accomplished by implementing controls. There are 4 effective approaches to select the co

CNSS Security model, "Using the CNSS Model, examine each of the cells and w...

"Using the CNSS Model, examine each of the cells and write a brief statement on how you would address the components respesented in that cell"

Calculate the minimum required signal strength, Question 1: (a) (i) Ra...

Question 1: (a) (i) Radio waves are subject to several propagation problems. Name any three of them. (ii) A Wi-Fi receiver requires a signal power of 50mW to operate correc

Determine the round trip time, a) determine the RTT (round trip time) betwe...

a) determine the RTT (round trip time) between a client requesting a web page of 1024 bytes in size from an internal web server on a 100 Base-T Ethernet. Assume a one-way propagati

Systems development life cycle security-information security, The Role of t...

The Role of the Investigation The first phase, investigation is the most significant. What problem is the system being developed to solve? During investigation phase, objectives

Computer forensic, discuss the merits and demerits of computers freezing

discuss the merits and demerits of computers freezing

Technology, how can you enter the ASVAB practice test on line?

how can you enter the ASVAB practice test on line?

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