Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Gateways They transfer packets among network machines that have different protocols (e.g. between a WAN and a LAN). They access a packet formatted for one protocol and change
Attacks on Cryptosystems Attacks are attempts to achieve unauthorized access to secure communications have characteristically used brute force attacks. Attacker may alternatively
Question 1 a) Provide three advantages of using optical fiber. b) Distinguish between "Direct Sequence Modulation" and "Frequency Hopping" c) Decribe the purpose of using "
(a) What are the different architectures for wireless networks? (b) Explain how WEP authentication and encryption works, describe the vulnerability. (c) In what ways are secu
What key which if used to encrypt the ciphertext again would give back the plaintext (i.e. key is a weak key)? Define a formula for identifying weak keys for the cipher below (
Q1 (15 marks, 5 marks each part): This question has three parts: In a short paragraph (200-300 words) explain the fundamentals of Packet Switching and how it works. In a short pa
Question: (a) Explain and illustrate with a drawing the three-layer feedforward multilayer perceptron neural network. (b) Summarize the standard backpropagation algorithm in
Write down short notes on the architecture of WWW which is World Wide Web. WWW which means The World Wide web or the web is a repository of information spread worldwide and rel
Listing Assets in Order of Importance Weighting should be created for each category based on the answers to questions. The relative importance of each asset is calculated usin
Question: (a) African governments are slowly shifting to more transparent ICT regulations. However, but limited spectrum availability remains a key barrier to sustaining lon
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd