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

Differentiate between private key and public key encryption, Problem (...

Problem (a) Differentiate between private key and public key encryption. (b) What issue with private key encryption is resolved with public key encryption? (c) Describe

What you understand by the term brute force attack, Question: a) Expla...

Question: a) Explain what you understand by the term brute force attack, giving an example of such an attack b) Briefly outline the concept of Caesar cipher and identify a

Simplex data exchange, Simplex data exchange Simplex communication def...

Simplex data exchange Simplex communication defines to communication that happens in one direction only. Two definitions have made over time: a common definition, which is des

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

Balancing security and access-information security, BALANCING SECURITY AND ...

BALANCING SECURITY AND ACCESS Even with best planning and implementation, it is impossible to obtain perfect security, that is, it is a process, not an absolute. Security should

Packet filtering firewall, Packet Filtering Firewall Packet filtering i...

Packet Filtering Firewall Packet filtering is a network security mechanism that works by controlling what data can flow in and out of the network. The basic device that interco

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

Ucsf medical center case study-information security, Example : UCSF Medical...

Example : UCSF Medical Center In the year 2002, the University of California, San Francisco (UCSF) Medical Center received an email message from someone who claimed to be a doct

Limitations of firewall, Limitations of firewall Firewalls cannot prote...

Limitations of firewall Firewalls cannot protect a network if security rules are not followed properly by an organization or if the rules are not defined properly. Firewalls ar

Security analysis-information security, SECURITY ANALYSIS Overview •    ...

SECURITY ANALYSIS Overview •    Know yourself: examine, identify, and understand the information and systems which are currently in place •    Know the enemy: examine, identify,

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