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

Risk identification-information security, Risk Identification Risk manag...

Risk Identification Risk management comprises of identifying, classifying and prioritizing organization’s information assets, threats and vulnerabilities also. Risk Identificati

Datagram reassembly, DATAGRAM REASSEMBLY Recreation of original datagr...

DATAGRAM REASSEMBLY Recreation of original datagram is known as reassembly. Ultimate receiver acts reassembly as given below.Fragments can reach out of order. Header bit check

Improving domain blacklisting - spam mail, Improving domain blacklisting: ...

Improving domain blacklisting: Current domain blacklisting techniques are not very effective as spammers keep replacing blacklisted domains with newly registered domains. Also

What are the main objectives of a risk analysis, QUESTION 1 Risk ana...

QUESTION 1 Risk analysis helps companies prioritize their risks and shows management the amount of money that should be applied to protecting against those risks in a sensib

Spambot detection - spam mail, Spambot Detection: The  previous studie...

Spambot Detection: The  previous studies in this field  have focused on content and meta-content based features.  The main assumption in this area of spam detection of late is

Explain the dimension of service quality, Problem 1: Discuss how TWO of...

Problem 1: Discuss how TWO of the following gurus have contributed to the Quality Movement, highlighting the major points of their philosophies: (a) Edward Deming (b) Jose

Arp message format, ARP MESSAGE FORMAT Although the ARP data packet fo...

ARP MESSAGE FORMAT Although the ARP data packet format is sufficiently general to allow hardware addresses and arbitrary protocol. ARP is almost usually used to bind a 32-bit

Important features of application layer, Describe the important features of...

Describe the important features of application layer. The features of the application layer are as follows. 1. Efficient User Interface Design is explained below: Appli

Assignment, Hello i have submitted an assignment and i am still waiting to ...

Hello i have submitted an assignment and i am still waiting to know if it has been accepted or not the ref number is TicketID: EM201381BRY525CN, the due date is for monday 27th of

Who are the individuals who cause these security problems, Who are the indi...

Who are the individuals who cause these security problems? Many unauthorized people who cause network security problems for obtaining information about the other users and causi

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