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

Issue specific security policy, Why an organization need the issue specific...

Why an organization need the issue specific security policy

Symmetric encryption-cryptography, Symmetric Encryption This encryption ...

Symmetric Encryption This encryption method makes use of same “secret key” to encipher and decipher the message and it is termed as private key encryption. This type of encrypti

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

Wireless sensor networks, The project will be involving a design and a repo...

The project will be involving a design and a report of which explain the simulation and how it functions. The aim of the project is to help the administrators and staff at the war

Ipv6 addressing, IPv6 ADDRESSING IPv6 has 128-bit addresses. A 128-bit...

IPv6 ADDRESSING IPv6 has 128-bit addresses. A 128-bit address adds network prefix and host suffix. An benefit of IPv6 addressing is that there is address classes i.e. prefix/s

Calculate the rsa public and private keys, (a) Which PKI (Public Key Infra...

(a) Which PKI (Public Key Infrastructure) model is typically favored by business organization? (b) Give one possible use of the "extensions" field of an X.509 certificate

Risk control strategies-risk management, Risk Control Strategies Once th...

Risk Control Strategies Once the ranked vulnerability risk worksheet has created, they should choose one of following 4 strategies to control each risk: •    Apply safeguards wh

Address masks, ADDRESS MASKS To identify receiver, network apply addre...

ADDRESS MASKS To identify receiver, network apply address mask to receiver address and calculate to network address in routing table. It can use Boolean 'and' to calculate the

Define repeater, Repeater known as regenerator ; it is an electronic mac...

Repeater known as regenerator ; it is an electronic machine that performs only at physical layer. It gets the signal in the network before it becomes loss or weak, recreates the

Professional issues in information technology, Thinking ethically is diffic...

Thinking ethically is difficult without a background in moral philosophy. Asking people to embrace ethics without offering practical explanation of the efficacy of so doing, is a t

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