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

Describe how ipsec provides data source authentication, Question: (a) ...

Question: (a) Describe how IPSec provides data source authentication. (b) Which protocol can be used to provide limited traffic analysis confidentiality? Why is it "limite

Risk assessment, RISK ASSESSMENT Risk assessment is a step in a risk man...

RISK ASSESSMENT Risk assessment is a step in a risk management technique. Risk assessment is the determination of quantitative or qualitative value of risk related to a concrete

Write pseudocode for the password guessing algorithm, Write Pseudocode for ...

Write Pseudocode for the password guessing algorithm: Consider the following authentication protocol: Client Transmission Host

Virtual terminal protocol vtp, Write down the short notes on VTR.  Communic...

Write down the short notes on VTR.  Communication between different types of the equipment and software is made possible by making use of the networks. Full-screen text editor is s

Udp datagram format, UDP DATAGRAM FORMAT: It is given in the figure be...

UDP DATAGRAM FORMAT: It is given in the figure below:

What is internet, The Internet is known as the set of networks connect...

The Internet is known as the set of networks connected by routers that are configured to pass traffic among any machine attached to any network in the set. By internet several

The major decision hierarchy for disclosing security problem, QUESTION ...

QUESTION The major decision hierarchy for disclosing security problems is if the problem is with the product owned by the business or if it is used by the business. Although th

Configure a router from command line interface, QUESTION (a) Describe ...

QUESTION (a) Describe the difference between static routing and dynamic routing algorithms. (b) List four functions that are performed by the Cisco IOS software during b

Describe the five-layer network using block diagrams, Problem 1: a) One...

Problem 1: a) One of the limitations of file processing systems is data inconsistency. Briefly explain with the help of an example what do you understand by this phrase. b)

Explain the terms used in network security, Question 1 (a) Explain b...

Question 1 (a) Explain briefly the following terms as used in network security: (i) Denial of service (DoS) attack (ii) Birthday attack (iii) DeMilitarized Zone

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