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

Example bus network , Ethernet is a commonly used LAN technology. It was di...

Ethernet is a commonly used LAN technology. It was discovered at EXROX PARC(Palo Alto Research Center) in 1970s.Xerox, Intel and Digital described it in a standard so it is also kn

Feasibility studies-risk management, Feasibility Studies Before deciding...

Feasibility Studies Before deciding on strategy, all information of economic or non economic consequences of vulnerability of information asset should be explored. A number of w

Network management system, Question (a) Draw a typical hybrid star-rin...

Question (a) Draw a typical hybrid star-ring topology paying attention to how the clients and switching hubs are connected. (b) State 3 main differences between a router

Frame format and error detection, FRAME FORMAT AND ERROR DETECTION The...

FRAME FORMAT AND ERROR DETECTION The changed frame format also adds CRC. If there is an error happened in frame, then it typically causes receiver to removed frame. The frame

Marketing, what are the participant of marketing channal?

what are the participant of marketing channal?

Network security, Network security has become much more complex than ever b...

Network security has become much more complex than ever before. New types and sources of network security threats, always-on high-speed Internet connections, wireless networking, a

Mobile wireless networks , Is standard TCP effective in mobile wireless net...

Is standard TCP effective in mobile wireless networks that operate with the IEEE 802.11 wireless local area network protocol?Discuss the issue

The cost benefit analysis (cba) formula, The Cost Benefit Analysis (CBA) Fo...

The Cost Benefit Analysis (CBA) Formula CBA determines that whether the control alternative being evaluated is worth cost incurred to control vulnerability or not. CBA easily ca

Log file monitors-information security, LOG FILE MONITORS Log file monit...

LOG FILE MONITORS Log file monitor (LFM) is similar to NIDS. It reviews log files generated by servers, network devices, and even other IDSs for patterns and signatures. Pattern

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