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

Introduction to network protocol, In this assignment, you are required to e...

In this assignment, you are required to emulate the operation of a link layer and network layer protocols in a small computer network. Your program should behave like a single node

Explain quality management system, Question: Quality management standar...

Question: Quality management standards are seen as a major pillar supporting the drive for continuous quality improvement through TQM. (a) What do you meant by the term ‘Qua

Fragmentation and path mtu, FRAGMENTATION AND PATH MTU IPv6 source is ...

FRAGMENTATION AND PATH MTU IPv6 source is responsible for fragmentation. Routers simply drop datagrams bigger than network MTU. So source have to fragment datagram to arrive d

Tcp- reliable transport service, TCP-RELIABLE TRANSPORT SERVICE INTRO...

TCP-RELIABLE TRANSPORT SERVICE INTRODUCTION:  TCP is the major transport protocol architecture in the TCP/IP suite. It uses unreliable datagram function offered by IP whe

Risk management discussion points, Risk Management Discussion Points Org...

Risk Management Discussion Points Organizations should define level of risk it can live with Risk appetite: it defines quantity and nature of risk which organizations are wil

What is a firewall, QUESTION (a) Define and distinguish between Electro...

QUESTION (a) Define and distinguish between Electronic Commerce and Electronic Business (b) According to you what are the benefits that Electronic Commerce can brings to org

Guided media, Guided Media These are those that give a conduit from on...

Guided Media These are those that give a conduit from one machine to another that add twisted-pair, fiber-optic cable and coaxial cable. A signal traveling along any of these

Important network security services, Question: (a) Consider that you en...

Question: (a) Consider that you enter the given URL in the address bar of a popular web client and that both the client and server accepts HTTP version 1.1. i. What can be t

What is authentication? explain authentication protocols, What is Authentic...

What is Authentication/confirmation?  How it is different from  the Authorization/approval?  Explain in brief different authentication protocols along with their merits and demerit

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