www.vustudents.ning.com

We non-commercial site working hard since 2009 to facilitate learning Read More. We can't keep up without your support. Donate.

# CS315 2nd Assignment

 Assignment No. 02 Semester: Spring 2018 Network Security-CS315 Total Marks: 20   Due Date: 04/06/2018 Instructions:                           Please read the following instructions carefully before submitting assignment: §  You will submit your assignment before or on due date on VU-LMS. §  Assignment should be completed by your own efforts it should not be copied from internet, handouts or books. §  You should submit your .doc File via assignment interface at VU-LMS. §  Assignment sent via Email will not be replied and accepted in any case. §  If the submitted assignment does not open or file is corrupt, it will not be marked. §  You will submit solution only in document (.doc or .docx) File. Objectives:   To build the proper understanding of following topics: a)    Hash Function b)    Encryption Algorithm For any query about the assignment, contact at cs315@vu.edu.pk Assignment Questions Question :                                                                                                                                                 Marks 20       Part a)  10 marks   Suppose a hacker is trying to attack a secure hash function. Calculate the following to know the level of effort required by hacker if the hash code is of length ‘16’: ·         Pre-image resistant ·         Second pre-image resistant           ·         Collision resistant     Part b)  10 marks   Consider a very simple symmetric block encryption algorithm in which 32-bits blocks of plaintext are encrypted using a 64-bit key. Encryption is defined as   C = (P ⊕ K0) + K1   Where C  = ciphertext,   K secret  = key,   K0  = leftmost 64 bits of K,   K1  = rightmost 64 bits of K,   ⊕ = bitwise exclusive OR,   + and is addition mod 264.   i. Show the decryption equation. That is, show the equation for P as a function of C, K0, and K1.   ii. Suppose and adversary has access to two sets of plaintexts and their corresponding ciphertexts and wishes to determine K.We have the two equations: C (P K0) K1; C' (P' K0) K1   First, derive an equation in one unknown (e.g., K0). Is it possible to proceed further to solve for K0?

Views: 342

Attachments:

### Replies to This Discussion

Our main purpose here discussion not just Solution

We are here with you hands in hands to facilitate your learning and do not appreciate the idea of copying or replicating solutions. Read More>>

Discussed & be touched with this discussion. After discussion a perfect solution will come in a result at the end.

Note:-

For Important Helping Material related to this subject (Solved MCQs, Short Notes, Solved past Papers, E-Books, FAQ,Short Questions Answers & more). You must view all the featured Discussion in this subject group.

For how you can view all the Featured discussions click on the Back to Subject Name Discussions link below the title of this Discussion & then under featured Discussion corner click on the view all link.

Or visit this link

&

.•°How to Download past papers from study groups°•.

Please Click on the below link to see…

.... How to Find Your Subject Study Group & Join ....

P.S:    Please always try to add the discussion in proper format title like “CS101 Assignment / GDB No 01 Solution & Discussion Due Date: ___________”

I need past papers of mid cs315 anyone have?

Searched alot on googl but couldn't got.

no past paper for this subject you have to prepare it on your own.

1

2

3

4

5

## Latest Activity

Derrick Bozem is now a member of Virtual University of Pakistan
41 minutes ago
20 hours ago
20 hours ago
20 hours ago
23 hours ago
23 hours ago
yesterday