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

Public key infrastructure (pki)-cryptography, Public Key Infrastructure (PK...

Public Key Infrastructure (PKI) It is integrated system of software, encryption methodologies, protocols, legal agreements, and 3rd-party services enabling users to communicate

Systems development life cycle (sdlc)-information security, SDLC Systems ...

SDLC Systems development life cycle (SDLC) is process of developing information systems through analysis, design, investigation, implementation and maintenance. SDLC is called as

Understanding a business model of a spammer, The first and foremost need of...

The first and foremost need of  any business is a role to perform for its client base, and for the spammer this will typically be the role of advertising products which, due to the

Discuss the importance of ontologies in agent communication, Question 1...

Question 1 The speech act theory is used as the model for communication among computational agents. Locution, illocution, and perlocution are the 3 aspects of this theory Using

Ipv6 datagram format, IPV6 DATAGRAM FORMAT It is given in the figure b...

IPV6 DATAGRAM FORMAT It is given in the figure below:

Explain how ethernet deals with collisions, (a) Describe how CSMA/CD operat...

(a) Describe how CSMA/CD operates and explain how Ethernet deals with collisions. (b) Describe how the subsequent protocols work: i. ARP ii. DHCP iii. DNS iv. SMTP (c) The

Explain major differences between wpa and wpa2, Question: Suppose the f...

Question: Suppose the following brief history of WLAN security standards: When the security of WEP was broken, the industry turned to the IEEE to fix it. The IEEE said it could

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

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

Udp encapsulation, UDP ENCAPSULATION As given in the figure below, UDP...

UDP ENCAPSULATION As given in the figure below, UDP packet is included in IP datagram and the IP datagram is then attached in the Frame.

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