Database System Concepts
7th Edition
ISBN: 9780078022159
Author: Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Related questions
Question
thumb_up100%
Cryptography. Can you do question 1 & 2 please
Transcribed Image Text:Consider a Feistel cipher with r rounds and n = 128 (half the block length); = 256 (the key
bit size). Then M = {0, 13256 (the plaintext space), C = {0, 11256 (the ciphertext space), and
X= {0, 13256 (the key space). A key scheduling algorithm determines subkeys k₁, k₂ from a key
KEK = {0, 13256. Each subkey k, determines a function f {0, 1128 {0, 1}128. Encryption
takes r rounds:
:
Plaintext is m = (mo, m₁) with mo, m₁ = {0, 1}128,
Round 1: (mo, m₁)→ (m₁, m₂) with m₂ = mo fi(m₁).
Round 2: (m₁, m₂)→ (m2, m3) with m3 = m₁ + f₂(m₂).
⠀
Round r: (m,-1, m,) → (mr, mr+1) with mr+1 = mr-1 fr (m₂).
The ciphertext is c = (mr, mr+1).
For the Feistel cipher described above:
1. Describe an algorithm for the decryption process for a ciphertext input c = -(m,, m,+1). You
should use a notation similar to the encryption procedure as described above.
2. Draw a figure for your decryption algorithm.
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution
Trending nowThis is a popular solution!
Step by stepSolved in 3 steps with 3 images
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.Similar questions
- Answer the following in a 2- to 3-page paper: Define cryptographic hash function (CFH). List and define the main properties of an ideal cryptographic hash function. Give at least 2 applications or uses for a CFH (example: password verification) and a brief description of how it is used. Format your paper according to appropriate course-level APA guidelines.arrow_forwardPlease write a new overview for this question that is not the same as the one already available for reveiw. Perform a Web search for “Announcing the Advanced Encryption Standard (AES).” Read this document, which is a FIPS 197 standard. Write a short overview of the development and implementation of this cryptosystem.arrow_forwardDiscuss the concept of a cryptographic hash function and its applications in data verification.arrow_forward
- Describe the difference between symmetric-key cryptography and public-key cryptography. Relate your discussion to the notion of ‘keys’, and also explain scenarios in which symmetric-key cryptography is better suited, and scenarios in which public-key cryptography is better suited.arrow_forward8. Differentiate between Symmetric Key and Asymmetric key cryptography.Write five examples of each type.arrow_forwardQuestion 9 Full explain this question and text typing work only thanksarrow_forward
- Can you provide any light on why authentication is a challenge in the modern era of information?arrow_forwardSo, what's the difference between conventional and symmetric key cryptography?arrow_forwardDiscuss in detail is public-key (asymmetric) encryption more secure from cryptanalysis than symmetric encryption?arrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- Database System ConceptsComputer ScienceISBN:9780078022159Author:Abraham Silberschatz Professor, Henry F. Korth, S. SudarshanPublisher:McGraw-Hill Education
Starting Out with Python (4th Edition)Computer ScienceISBN:9780134444321Author:Tony GaddisPublisher:PEARSON
Digital Fundamentals (11th Edition)Computer ScienceISBN:9780132737968Author:Thomas L. FloydPublisher:PEARSON 
C How to Program (8th Edition)Computer ScienceISBN:9780133976892Author:Paul J. Deitel, Harvey DeitelPublisher:PEARSON
Database Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781337627900Author:Carlos Coronel, Steven MorrisPublisher:Cengage Learning
Programmable Logic ControllersComputer ScienceISBN:9780073373843Author:Frank D. PetruzellaPublisher:McGraw-Hill Education
Database System Concepts
Computer Science
ISBN:9780078022159
Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:McGraw-Hill Education
Starting Out with Python (4th Edition)
Computer Science
ISBN:9780134444321
Author:Tony Gaddis
Publisher:PEARSON
Digital Fundamentals (11th Edition)
Computer Science
ISBN:9780132737968
Author:Thomas L. Floyd
Publisher:PEARSON
C How to Program (8th Edition)
Computer Science
ISBN:9780133976892
Author:Paul J. Deitel, Harvey Deitel
Publisher:PEARSON
Database Systems: Design, Implementation, & Manag...
Computer Science
ISBN:9781337627900
Author:Carlos Coronel, Steven Morris
Publisher:Cengage Learning
Programmable Logic Controllers
Computer Science
ISBN:9780073373843
Author:Frank D. Petruzella
Publisher:McGraw-Hill Education