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

Why use an ids, WHY USE AN IDS? IDS prevent from problem behaviors by in...

WHY USE AN IDS? IDS prevent from problem behaviors by increasing the perceived risk of discovery and punishment. Detect the attacks and other security violations. Detect and at

Wfabilling project in java, WFABilling project in Java:  Project Title...

WFABilling project in Java:  Project Title: WFABilling   Role                      : Developer Domain                 : Tele-Com Environment          : Java, J2EE, S

Tcp and udp, TCP and UDP End-to-end delivery application is connection...

TCP and UDP End-to-end delivery application is connection less. The basic function of connectionless service are as given: It adds extension of LAN abstraction. It has simp

Define packet, CONCEPT OF PACKET : Network systems splits data in small ...

CONCEPT OF PACKET : Network systems splits data in small junks or blocks known as packets, which they send individually. Why we required packets rather than bits? The answer to

Emerging threats related to use of networks, Question requires you to submi...

Question requires you to submit a proposal based on the research report topic you will be addressing in the second assignment.  Note:  before commencing research on the topic, y

Briefly explain the contents of the needs analysis, QUESTION (a) Brief...

QUESTION (a) Briefly explain the contents of the Needs Analysis, which is step in the process of network design. (b) Describe on the three ways of improving the performan

Explain rsa encryption, (a) Describe RSA encryption. (b) For an RSA encr...

(a) Describe RSA encryption. (b) For an RSA encryption the values of the primes are: p=29, q=31. select e=11, evaluate the public and private keys. (c) How can RSA be used fo

Fragmentation, FRAGMENTATION One method is to limit datagram size to s...

FRAGMENTATION One method is to limit datagram size to smallest MTU of any server. IP needs fragmentation i.e. datagrams can be divided into pieces to fit in network with small

Transmision imparment, What are Transmission Impairments? Explain the follo...

What are Transmission Impairments? Explain the following concepts with respect to Transmission Impairments a) Attenuation b) Delay Distortion c) Noise ion #Minimum 100 words ac

Ip datagram format, IP DATAGRAM SIZE:  Datagrams may have different si...

IP DATAGRAM SIZE:  Datagrams may have different sizes i.e. Header area is generally fixed (20 octets) but can have various options. Data area may contain between 1 octet and 6

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