Networks Encryption.

Slides:

Advertisements

Similar presentations

CLASSICAL ENCRYPTION TECHNIQUES

Advertisements

Computer Science 101 Data Encryption And Computer Networks.

Cryptology Terminology and Early History. Cryptology Terms Cryptology –The science of concealing the meaning of messages and the discovery of the meaning.

Creating Secret Messages. 2 Why do we need to keep things secret? Historically, secret messages were used in wars and battles For example, the Enigma.

CPSC CPSC 3730 Cryptography Chapter 2 Classical Encryption Techniques.

8: Network Security8-1 Symmetric key cryptography symmetric key crypto: Bob and Alice share know same (symmetric) key: K r e.g., key is knowing substitution.

Chapter 2 – Classical Encryption Techniques

Encryption. Introduction Computer security is the prevention of or protection against –access to information by unauthorized recipients –intentional but.

Cryptography Week-6.

Cryptography and Network Security (CS435) Part Two (Classic Encryption Techniques)

Chapter 17 Security. Information Systems Cryptography Key Exchange Protocols Password Combinatorics Other Security Issues 12-2.

An Introduction to Cryptography. What is cryptography? noun \krip- ˈ tä-grə-fē\ : the process of writing or reading secret messages or codes “Encryption”:

Data Security and Encryption (CSE348) 1. Lecture # 3 2.

CRYPTOGRAPHY. TOPICS OF SEMINAR Introduction & Related Terms Categories and Aspects of cryptography Model of Network Security Encryption Techniques Public.

Some of these PowerPoint pages were created by my friend Shawna Haider.

Lecture 3 Page 1 CS 236 Online Introduction to Cryptography CS 236 On-Line MS Program Networks and Systems Security Peter Reiher.

How the internet works Cryptography. LO: Define the terms encryption and decryption Construct a secure message using encryption LO: Define the terms encryption.

Computer Security By Rubel Biswas. Introduction History Terms & Definitions Symmetric and Asymmetric Attacks on Cryptosystems Outline.

CRYPTOGRAPHY Cryptography is art or science of transforming intelligible message to unintelligible and again transforming that message back to the original.

Lecture 3 Page 1 CS 236 Online Basic Encryption Methods Substitutions –Monoalphabetic –Polyalphabetic Permutations.

Cryptography Introduction. Definition Origin Objectives Terminologies References Agenda.

CRYPTOGRAPHY G REEK WORD MEANING “ SECRET WRITING ”

CMSC 414 Computer (and Network) Security Lecture 3 Jonathan Katz.

Encryption with Keys and Passwords

Vocabulary Big Data - “Big data is a broad term for datasets so large or complex that traditional data processing applications are inadequate.” Moore’s.

Cracking Encrypted Systems

Key words: Cryptography | Binary | Cipher

USAGE OF CRYPTOGRAPHY IN NETWORK SECURITY

Vocabulary Big Data - “Big data is a broad term for datasets so large or complex that traditional data processing applications are inadequate.” Moore’s.

Vocabulary Big Data - “Big data is a broad term for datasets so large or complex that traditional data processing applications are inadequate.” Moore’s.

Introduction Of System Security

Basic Encryption Methods

Topics discussed in this section: 30-2 SYMMETRIC-KEY CRYPTOGRAPHY Symmetric-key cryptography started thousands of years ago when people needed.

Chapter-2 Classical Encryption Techniques.

Vocabulary Big Data - “Big data is a broad term for datasets so large or complex that traditional data processing applications are inadequate.” Moore’s.

CSCI-235 Micro-Computer Applications

Lesson 4-5 AP Computer Science Principles

Lecture 3: Symmetric Key Encryption

Crypto 101 & Password Cracking

Topic 3: Data Encryption.

M3: Encryption r By Andrew Stringer.

Lesson 5: Simple Encryption

User access levels, Passwords, Encryption, Cipher, Key

Chapter 3:Cryptography (16M)

Unit 1.6 Systems security Lesson 4

Encryption with Keys and Passwords

NET 311D Information Security

Encryption and Decryption

Cryptography “The Secret Code Language”

Cryptography and Network Security

Information Security Tanachat Arayachutinan

Simple Encryption- Lesson 5

Substitution Codes By Sarah Bonnell.

Encryption with Keys and Passwords

Cryptography a Presentation Prepared by Vytautas Kondratas.

Lesson 7: Simple Encryption

Cryptography: Cesar Cipher

Network and Data Security

GCSE COMPUTER SCIENCE Topic 3 - Data 3.10 Encryption.

Double Transpositions

Computer Security Chapter Two

Types of Cryptanalysis attacks

Cryptanalysis Network Security.

Symmetric Encryption or conventional / private-key / single-key

Chapter Goals Define cryptography

1.3 Compression, Encryption & Hashing

10/7/2019 Created by Omeed Mustafa 1 st Semester M.Sc (Computer Science department) Cyber-Security.

Presentation transcript:

Networks Encryption

Objective To identify some of the data which should be kept secure from others. To learn some of the ways in which data is kept secure. To learn how unauthorised people can break ciphers and read encrypted data. To learn about classical encryption techniques.

As a class, can we think of information which is secure to us? Security As a class, can we think of information which is secure to us? Is there any information which you wouldn’t like other people to get their hands on? (Discuss and make a list on the next slide) You may want to use post-its to begin with.

Security

Encryption In order to stop people from getting our information we encrypt the information. Data is changed so that people can no longer understand out messages. They need to have a secret key. Have you ever tried to send a secret message to your friends or family? You are about to decrypt a message! Use the worksheet online to find out what it says!

Decrypt this message

Terminology / Glossary Plaintext: The original message to be encrypted Cipher text: - The encrypted message Encryption: - Convert the plain text into cipher Encryption Algorithm: - The way of working out the plain text.

ATTACK!!! Brute Force: Sometimes when people are trying to get your information, they’ll try every possible key! This is why our passwords need to be secure. They will try every possible word in the dictionary before trying every possible key combination. An example of the brute-force attack is shown on the next slide.

ATTACK!!!

How they do it! Our language has a footprint. It detects how many times we use letters and these are the areas they focus on. This is why we should make our passwords secure!

Ceaser Shift Cipher Ceaser Shift Cipher: - Your teacher is going to show you this clip of the Ceaser Shift : https://vimeo.com/145990347 It was the earliest known substitution cipher invited by Julius Caeser. Each letter is replaced by the letter three positions further on in the alphabet.

Ceaser Shift Cipher

Activity: - Use the activity sheet to answer a series of questions about what you’ve learnt. Create your own message in plain text Create a key Create your Cipher Text Create a poster which includes your Cipher text and a blank space for people to solve your message. Try to crack each others messages.

Extension: Investigate the Enigma code and produce a presentation about how it was cracked. Who helped crack it? What was it? Where can you find the computer today?