# APNIC elearning: Cryptography Basics. Contact: esec02_v1.0

Save this PDF as:

Size: px
Start display at page:

## Transcription

1 APNIC elearning: Cryptography Basics Contact: esec02_v1.0

2 Overview Cryptography Cryptographic Algorithms Encryption Symmetric-Key Algorithm Block and Stream Cipher Asymmetric Key Algorithm Hash Functions Digital Signature

3 Cryptography Has evolved into a complex science in the field of information security German Lorenz cipher machine

4 Cryptography Cryptography deals with creating documents that can be shared secretly over public communication channels Other terms closely associated Cryptanalysis (breaking an encoded data without the knowledge of the key) Cryptology (combination of cryptography and cryptanalysis) Cryptography is a function of plaintext and a cryptographic key C = F(P, k) Notation: Plaintext (P) Ciphertext (C) Cryptographic Key (k)

5 Crypto Algorithms specifies the mathematical transformation that is performed on data to encrypt/decrypt Crypto algorithm is NOT proprietary Analyzed by public community to show that there are no serious weaknesses Explicitly designed for encryption 5

6 Typical Scenario Alice wants to send a secret message to Bob What are the possible problems? Data can be intercepted What are the ways to intercept this message? How to conceal the message? Old algorithms such as the substitution cipher

7 Types of Cipher Substitution cipher involves replacing an alphabet with another character of the same alphabet set Can be mono-alphabetic (single set for substitution) or polyalphabetic system (multiple alphabetic sets) Example: Caesar cipher, a mono-alphabetic system in which each character is replaced by the third character in succession Vigenere cipher, a poly-alphabetic cipher that uses a 26x26 table of characters

8 Transposition Cipher No letters are replaced, they are just rearranged. Rail Fence Cipher another kind of transposition cipher in which the words are spelled out as if they were a rail fence.

9 Encryption process of transforming plaintext to ciphertext using a cryptographic key Used all around us In Application Layer used in secure , database sessions, and messaging In session layer using Secure Socket Layer (SSL) or Transport Layer Security (TLS) In the Network Layer using protocols such as IPSec Benefits of good encryption algorithm: Resistant to cryptographic attack They support variable and long key lengths and scalability They create an avalanche effect No export or import restrictions Two general types: Symmetric and Asymmetric

10 Encryption and Decryption Plaintext ENCRYPTION ALGORITHM Ciphertext DECRYPTION ALGORITHM Plaintext Encryption Key Decryption Key

11 Symmetric Key Algorithm Uses a single key to both encrypt and decrypt information Also known as a secret-key algorithm The key must be kept a secret to maintain security This key is also known as a private key Follows the more traditional form of cryptography with key lengths ranging from 40 to 256 bits. Examples of symmetric key algorithms: DES, 3DES, AES, IDEA, RC5, RC6, Blowfish

12 Symmetric Encryption Plaintext ENCRYPTION ALGORITHM Ciphertext DECRYPTION ALGORITHM Plaintext Encryption Key Decryption Key Shared Key Shared Key Symmetric Key Cryptography Same shared secret key

13 Symmetric Key Algorithm DES block cipher using shared key encryption, 56-bit 3DES (Triple DES) a block cipher that applies DES three times to each data block AES replacement for DES; it is the current standard IDEA RC4 variable-length key, stream cipher (generate stream from key, XOR with data) RC6 Blowfish

14 Symmetric Key Algorithm Symmetric Algorithm DES Triple DES (3DES) AES IDEA RC2 RC4 RC5 RC6 Blowfish Key Size 56-bit keys 112-bit and 168-bit keys 128, 192, and 256-bit keys 128-bit keys 40 and 64-bit keys 1 to 256-bit keys 0 to 2040-bit keys 128, 192, and 256-bit keys 32 to 448-bit keys Note: Longer keys are more difficult to crack, but more computationally expensive.

15 Block and Stream Cipher Block cipher takes a block of bits and encrypts them as a single unit operate on a pre-determined block of bits (one byte, one word, 512 bytes, so forth), mixing key data in with the message data in a variety of different ways. Stream cipher encrypts bits of the message at a time typically bit-wise. They either have a very long key (that eventually repeats) or a reusable key that generates a repeatable but seemingly random string of bits. They perform some operation (typically an exclusive OR) with one of these key bits and one of the message bits.

16 Block Cipher Transforms a fixed-length block of plain text into a block of ciphertext Works with data per block Common block ciphers: DES and 3DES (in ECB and CBC mode) Skipjack Blowfish RSA AES IDEA Secure and Fast Encryption Routing (SAFER)

17 Stream Cipher Use smaller units of plaintext than what are used with block ciphers. Typically work with bits Common stream ciphers: RC4 DES and 3DES (running OFB or CFB mode) Software encryption algorithm (SEAL)

18 Data Encryption Standard (DES) Developed by IBM for the US government in , and approved in Nov Based on Horst Feistel s Lucifer cipher block cipher using shared key encryption, 56-bit key length Block size: 64 bits

19 Triple DES 3DES (Triple DES) a block cipher that applies DES three times to each data block Uses a key bundle comprising of three DES keys (K1, K2, K3), each with 56 bits excluding parity. DES encrypts with K1, decrypts with K2, then encrypts with K3 Disadvantage: very slow C i = E K 3 (D K 2 (E K1 (P i )))

20 3DES: Illustration Plaintext ENCRYPT DECRYPT ENCRYPT Ciphertext Key 1 Key 2 Key 3 Note: If Key1 = Key2 = Key3, this is similar to DES Usually, Key1 = Key3

21 Advanced Encryption Standard (AES) Published in November 2001 Symmetric block cipher Has a fixed block size of 128 bits Has a key size of 128, 192, or 256 bits Based on Rijndael cipher which was developed by Joan Daemen and Vincent Rijmen Better suited for high-througput, low latency environments

22 Rivest Cipher RC Algorithm RC2 RC4 RC5 RC6 Description Variable key-sized cipher used as a drop in replacement for DES Variable key sized stream cipher; Often used in file encryption and secure communications (SSL) Variable block size and variable key length; uses 64-bit block size; Fast, replacement for DES Block cipher based on RC5, meets AES requirement

23 RC4 Most widely used stream cipher Popularly used in Secure Socket Layer (SSL) and Wired Equivalent Privacy (WEP) protocols Although simple and fast, it is vulnerable and can lead to insecure systems

24 Block Cipher Modes Defines how the block cipher algorithm is applied to the data stream Four Basic Modes Electronic Code Book (ECB) Cipher Block Chaining (CBC) Cipher Feedback (CFB) Output Feedback (OFB) 24

25 Asymmetric Key Algorithm Also called public-key cryptography Keep private key private Anyone can see public key separate keys for encryption and decryption (public and private key pairs) Examples of asymmetric key algorithms: RSA, DSA, Diffie-Hellman, El Gamal, Elliptic Curve and PKCS

26 Asymmetric Encryption Plaintext ENCRYPTION ALGORITHM Ciphertext DECRYPTION ALGORITHM Plaintext Encryption Key Decryption Key Public Key Private Key Asymmetric Key Cryptography Different keys

27 Asymmetric Key Algorithm RSA the first and still most common implementation DSA specified in NIST s Digital Signature Standard (DSS), provides digital signature capability for authentication of messages Diffie-Hellman used for secret key exchange only, and not for authentication or digital signature ElGamal similar to Diffie-Hellman and used for key exchange PKCS set of interoperable standards and guidelines

28 RSA Public Key Cryptography Based on relative ease of multiplying large primes together but almost impossible to factor the resulting product RSA keys: 3 special numeric values Algorithm produces public keys that are tied to specific private keys Provides both digital signatures and public-key encryption 28

29 Symmetric vs. Asymmetric Key Symmetric generally fast Same key for both encryption and decryption Asymmetric Can be 1000 times slower Uses two different keys (public and private) Decryption key cannot be calculated from the encryption key Key lengths: 512 to 4096 bits Used in low-volume

30 Hash Functions produces a condensed representation of a message (hashing) The fixed-length output is called the hash or message digest A hash function takes an input message of arbitrary length and outputs fixed-length code. The fixed-length output is called the hash, or the message digest, of the original input message. A form of signature that uniquely represents the data Uses: Verifying file integrity - if the hash changes, it means the data is either compromised or altered in transit. Digitally signing documents Hashing passwords

31 Hash Functions Message Digest (MD) Algorithm Outputs a 128-bit fingerprint of an arbitrary-length input Secure Hash Algorithm (SHA) SHA-1 produces a 160-bit message digest similar to MD5 Widely-used on security applications (TLS, SSL, PGP, SSH, S/MIME, IPsec) SHA-256, SHA-384, SHA-512 are also commonly used, which can produce hash values that are 256, 384, and 512-bits respectively RIPEMD

32 Digital Signature A digital signature is a message appended to a packet The sender encrypts message with own private key instead of encrypting with intended receiver s public key The receiver of the packet uses the sender s public key to verify the signature. Used to prove the identity of the sender and the integrity of the packet

33 Digital Signature Process 1. Hash the data using one of the supported hashing algorithms (MD5, SHA-1, SHA-256) 2. Encrypt the hashed data using the sender s private key 3. Append the signature (and a copy of the sender s public key) to the end of the data that was signed) DATA MD5/SHA-1 HASH (DATA) PRIVATE KEY DIGITAL SIGNATURE

34 Signature Verification Process 1. Hash the original data using the same hashing algorithm 2. Decrypt the digital signature using the sender s public key. All digital signatures contain a copy of the signer s public key 3. Compare the results of the hashing and the decryption. If the values match then the signature is verified. If the values do not match, then the data or signature was probably modified. DATA MD5/SHA-1 HASH (DATA) MATCH? HASH (DIGITAL SIG)

35 Questions Please remember to fill out the feedback form <survey-link> Slide handouts will be available after completing the survey

36 APNIC Helpdesk Chat

37 Thank You! End of Session

### IT Networks & Security CERT Luncheon Series: Cryptography

IT Networks & Security CERT Luncheon Series: Cryptography Presented by Addam Schroll, IT Security & Privacy Analyst 1 Outline History Terms & Definitions Symmetric and Asymmetric Algorithms Hashing PKI

### Chapter 11 Security+ Guide to Network Security Fundamentals, Third Edition Basic Cryptography

Chapter 11 Security+ Guide to Network Security Fundamentals, Third Edition Basic Cryptography What Is Steganography? Steganography Process of hiding the existence of the data within another file Example:

### Security. Contents. S-72.3240 Wireless Personal, Local, Metropolitan, and Wide Area Networks 1

Contents Security requirements Public key cryptography Key agreement/transport schemes Man-in-the-middle attack vulnerability Encryption. digital signature, hash, certification Complete security solutions

### Network Security. Security Attacks. Normal flow: Interruption: 孫 宏 民 hmsun@cs.nthu.edu.tw Phone: 03-5742968 國 立 清 華 大 學 資 訊 工 程 系 資 訊 安 全 實 驗 室

Network Security 孫 宏 民 hmsun@cs.nthu.edu.tw Phone: 03-5742968 國 立 清 華 大 學 資 訊 工 程 系 資 訊 安 全 實 驗 室 Security Attacks Normal flow: sender receiver Interruption: Information source Information destination

### Cryptography & Network Security

Cryptography & Network Security Lecture 1: Introduction & Overview 2002. 3. 27 chlim@sejong.ac.kr Common Terms(1) Cryptography: The study of mathematical techniques related to aspects of information security

### Computer Security: Principles and Practice

Computer Security: Principles and Practice Chapter 20 Public-Key Cryptography and Message Authentication First Edition by William Stallings and Lawrie Brown Lecture slides by Lawrie Brown Public-Key Cryptography

### Dr. Jinyuan (Stella) Sun Dept. of Electrical Engineering and Computer Science University of Tennessee Fall 2010

CS 494/594 Computer and Network Security Dr. Jinyuan (Stella) Sun Dept. of Electrical Engineering and Computer Science University of Tennessee Fall 2010 1 Introduction to Cryptography What is cryptography?

### EXAM questions for the course TTM4135 - Information Security May 2013. Part 1

EXAM questions for the course TTM4135 - Information Security May 2013 Part 1 This part consists of 5 questions all from one common topic. The number of maximal points for every correctly answered question

### Chapter 8. Network Security

Chapter 8 Network Security Cryptography Introduction to Cryptography Substitution Ciphers Transposition Ciphers One-Time Pads Two Fundamental Cryptographic Principles Need for Security Some people who

### Network Security. Abusayeed Saifullah. CS 5600 Computer Networks. These slides are adapted from Kurose and Ross 8-1

Network Security Abusayeed Saifullah CS 5600 Computer Networks These slides are adapted from Kurose and Ross 8-1 Goals v understand principles of network security: cryptography and its many uses beyond

### Lecture 9: Application of Cryptography

Lecture topics Cryptography basics Using SSL to secure communication links in J2EE programs Programmatic use of cryptography in Java Cryptography basics Encryption Transformation of data into a form that

### Cryptography and Network Security

PART-A Questions 1. Name the aspects to be considered of information security. 2. What is meant by deciphering? 3. What are the two different uses of public key cryptography related to key distribution?

### CIS 6930 Emerging Topics in Network Security. Topic 2. Network Security Primitives

CIS 6930 Emerging Topics in Network Security Topic 2. Network Security Primitives 1 Outline Absolute basics Encryption/Decryption; Digital signatures; D-H key exchange; Hash functions; Application of hash

### Overview of Cryptographic Tools for Data Security. Murat Kantarcioglu

UT DALLAS Erik Jonsson School of Engineering & Computer Science Overview of Cryptographic Tools for Data Security Murat Kantarcioglu Pag. 1 Purdue University Cryptographic Primitives We will discuss the

### Network Security. Computer Networking Lecture 08. March 19, 2012. HKU SPACE Community College. HKU SPACE CC CN Lecture 08 1/23

Network Security Computer Networking Lecture 08 HKU SPACE Community College March 19, 2012 HKU SPACE CC CN Lecture 08 1/23 Outline Introduction Cryptography Algorithms Secret Key Algorithm Message Digest

1 Introduction to Cryptography and Data Security 1 1.1 Overview of Cryptology (and This Book) 2 1.2 Symmetric Cryptography 4 1.2.1 Basics 4 1.2.2 Simple Symmetric Encryption: The Substitution Cipher...

### Cryptography. some history. modern secret key cryptography. public key cryptography. cryptography in practice

Cryptography some history Caesar cipher, rot13 substitution ciphers, etc. Enigma (Turing) modern secret key cryptography DES, AES public key cryptography RSA, digital signatures cryptography in practice

### Network Security. Omer Rana

Network Security Omer Rana CM0255 Material from: Cryptography Components Sender Receiver Plaintext Encryption Ciphertext Decryption Plaintext Encryption algorithm: Plaintext Ciphertext Cipher: encryption

### CRYPTOGRAPHY IN NETWORK SECURITY

ELE548 Research Essays CRYPTOGRAPHY IN NETWORK SECURITY AUTHOR: SHENGLI LI INSTRUCTOR: DR. JIEN-CHUNG LO Date: March 5, 1999 Computer network brings lots of great benefits and convenience to us. We can

### 7! Cryptographic Techniques! A Brief Introduction

7! Cryptographic Techniques! A Brief Introduction 7.1! Introduction to Cryptography! 7.2! Symmetric Encryption! 7.3! Asymmetric (Public-Key) Encryption! 7.4! Digital Signatures! 7.5! Public Key Infrastructures

### Chapter 10. Network Security

Chapter 10 Network Security 10.1. Chapter 10: Outline 10.1 INTRODUCTION 10.2 CONFIDENTIALITY 10.3 OTHER ASPECTS OF SECURITY 10.4 INTERNET SECURITY 10.5 FIREWALLS 10.2 Chapter 10: Objective We introduce

### Network Security. HIT Shimrit Tzur-David

Network Security HIT Shimrit Tzur-David 1 Goals: 2 Network Security Understand principles of network security: cryptography and its many uses beyond confidentiality authentication message integrity key

### An Introduction to Cryptography as Applied to the Smart Grid

An Introduction to Cryptography as Applied to the Smart Grid Jacques Benoit, Cooper Power Systems Western Power Delivery Automation Conference Spokane, Washington March 2011 Agenda > Introduction > Symmetric

### Lecture 9 - Network Security TDTS41-2006 (ht1)

Lecture 9 - Network Security TDTS41-2006 (ht1) Prof. Dr. Christoph Schuba Linköpings University/IDA Schuba@IDA.LiU.SE Reading: Office hours: [Hal05] 10.1-10.2.3; 10.2.5-10.7.1; 10.8.1 9-10am on Oct. 4+5,

### USING ENCRYPTION TO PROTECT SENSITIVE INFORMATION Commonwealth Office of Technology Security Month Seminars October 29, 2013

USING ENCRYPTION TO PROTECT SENSITIVE INFORMATION Commonwealth Office of Technology Security Month Seminars Alternate Title? Boy, am I surprised. The Entrust guy who has mentioned PKI during every Security

### SECURITY IN NETWORKS

SECURITY IN NETWORKS GOALS Understand principles of network security: Cryptography and its many uses beyond confidentiality Authentication Message integrity Security in practice: Security in application,

### Cryptography: Motivation. Data Structures and Algorithms Cryptography. Secret Writing Methods. Many areas have sensitive information, e.g.

Cryptography: Motivation Many areas have sensitive information, e.g. Data Structures and Algorithms Cryptography Goodrich & Tamassia Sections 3.1.3 & 3.1.4 Introduction Simple Methods Asymmetric methods:

### Chapter 7: Network security

Chapter 7: Network security Foundations: what is security? cryptography authentication message integrity key distribution and certification Security in practice: application layer: secure e-mail transport

### Overview. SSL Cryptography Overview CHAPTER 1

CHAPTER 1 Secure Sockets Layer (SSL) is an application-layer protocol that provides encryption technology for the Internet. SSL ensures the secure transmission of data between a client and a server through

### Cryptography & Digital Signatures

Cryptography & Digital Signatures CS 594 Special Topics/Kent Law School: Computer and Network Privacy and Security: Ethical, Legal, and Technical Consideration Prof. Sloan s Slides, 2007, 2008 Robert H.

### 159.334 Computer Networks. Network Security 1. Professor Richard Harris School of Engineering and Advanced Technology

Network Security 1 Professor Richard Harris School of Engineering and Advanced Technology Presentation Outline Overview of Identification and Authentication The importance of identification and Authentication

### Network Security. Abusayeed Saifullah. CS 5600 Computer Networks. These slides are adapted from Kurose and Ross 8-1

Network Security Abusayeed Saifullah CS 5600 Computer Networks These slides are adapted from Kurose and Ross 8-1 Public Key Cryptography symmetric key crypto v requires sender, receiver know shared secret

### Network Security (2) CPSC 441 Department of Computer Science University of Calgary

Network Security (2) CPSC 441 Department of Computer Science University of Calgary 1 Friends and enemies: Alice, Bob, Trudy well-known in network security world Bob, Alice (lovers!) want to communicate

### CSCI-E46: Applied Network Security. Class 1: Introduction Cryptography Primer 1/26/16 CSCI-E46: APPLIED NETWORK SECURITY, SPRING 2016 1

CSCI-E46: Applied Network Security Class 1: Introduction Cryptography Primer 1/26/16 CSCI-E46: APPLIED NETWORK SECURITY, SPRING 2016 1 Welcome to CSCI-E46 Classroom & Schedule 53 Church Street L01 Wednesdays,

### CrypTool. www.cryptool.de www.cryptool.com www.cryptool.org. Claudia Eckert / Thorsten Clausius Bernd Esslinger / Jörg Schneider / Henrik Koy

CrypTool A free software program for creating awareness of IT security issues for learning about and obtaining experience of cryptography for demonstrating encryption algorithms and analysis procedures

### The Misuse of RC4 in Microsoft Word and Excel

The Misuse of RC4 in Microsoft Word and Excel Hongjun Wu Institute for Infocomm Research, Singapore hongjun@i2r.a-star.edu.sg Abstract. In this report, we point out a serious security flaw in Microsoft

### Authentication requirement Authentication function MAC Hash function Security of

UNIT 3 AUTHENTICATION Authentication requirement Authentication function MAC Hash function Security of hash function and MAC SHA HMAC CMAC Digital signature and authentication protocols DSS Slides Courtesy

### lundi 1 octobre 2012 In a set of N elements, by picking at random N elements, we have with high probability a collision two elements are equal

Symmetric Crypto Pierre-Alain Fouque Birthday Paradox In a set of N elements, by picking at random N elements, we have with high probability a collision two elements are equal N=365, about 23 people are

### Encryption, Data Integrity, Digital Certificates, and SSL. Developed by. Jerry Scott. SSL Primer-1-1

Encryption, Data Integrity, Digital Certificates, and SSL Developed by Jerry Scott 2002 SSL Primer-1-1 Ideas Behind Encryption When information is transmitted across intranets or the Internet, others can

### Network Security. Gaurav Naik Gus Anderson. College of Engineering. Drexel University, Philadelphia, PA. Drexel University. College of Engineering

Network Security Gaurav Naik Gus Anderson, Philadelphia, PA Lectures on Network Security Feb 12 (Today!): Public Key Crypto, Hash Functions, Digital Signatures, and the Public Key Infrastructure Feb 14:

### What is network security?

Network security Network Security Srinidhi Varadarajan Foundations: what is security? cryptography authentication message integrity key distribution and certification Security in practice: application

### Overview of CSS SSL. SSL Cryptography Overview CHAPTER

CHAPTER 1 Secure Sockets Layer (SSL) is an application-level protocol that provides encryption technology for the Internet, ensuring secure transactions such as the transmission of credit card numbers

### Overview. SSL Cryptography Overview CHAPTER 1

CHAPTER 1 Note The information in this chapter applies to both the ACE module and the ACE appliance unless otherwise noted. The features in this chapter apply to IPv4 and IPv6 unless otherwise noted. Secure

### CS 393 Network Security. Nasir Memon Polytechnic University Module 11 Secure Email

CS 393 Network Security Nasir Memon Polytechnic University Module 11 Secure Email Course Logistics HW 5 due Thursday Graded exams returned and discussed. Read Chapter 5 of text 4/2/02 Module 11 - Secure

### Chapter 8. Cryptography Symmetric-Key Algorithms. Digital Signatures Management of Public Keys Communication Security Authentication Protocols

Network Security Chapter 8 Cryptography Symmetric-Key Algorithms Public-Key Algorithms Digital Signatures Management of Public Keys Communication Security Authentication Protocols Email Security Web Security

### CIS433/533 - Computer and Network Security Cryptography

CIS433/533 - Computer and Network Security Cryptography Professor Kevin Butler Winter 2011 Computer and Information Science A historical moment Mary Queen of Scots is being held by Queen Elizabeth and

### APNIC elearning: IPSec Basics. Contact: training@apnic.net. esec03_v1.0

APNIC elearning: IPSec Basics Contact: training@apnic.net esec03_v1.0 Overview Virtual Private Networks What is IPsec? Benefits of IPsec Tunnel and Transport Mode IPsec Architecture Security Associations

### Message Authentication

Message Authentication message authentication is concerned with: protecting the integrity of a message validating identity of originator non-repudiation of origin (dispute resolution) will consider the

### Client Server Registration Protocol

Client Server Registration Protocol The Client-Server protocol involves these following steps: 1. Login 2. Discovery phase User (Alice or Bob) has K s Server (S) has hash[pw A ].The passwords hashes are

### Data Encryption WHITE PAPER ON. Prepared by Mohammed Samiuddin. www.itmr.ac.in

01 0110 0001 01101 WHITE PAPER ON Data Encryption Prepared by Mohammed Samiuddin www.itmr.ac.in Contents INTRODUCTION... 2 NEED FOR DATA ENCRYPTION... 3 DUE CARE... 3 REPUTATIONAL RISK... 3 REGULATORY

### CS 758: Cryptography / Network Security

CS 758: Cryptography / Network Security offered in the Fall Semester, 2003, by Doug Stinson my office: DC 3122 my email address: dstinson@uwaterloo.ca my web page: http://cacr.math.uwaterloo.ca/~dstinson/index.html

NETWORK ADMINISTRATION AND SECURITY Unit I (NAS) (W- 10) Q. 1) What is Security Attack? Explain general categories of attack with examples. 7 Q. 2) List and define the five security services. 5 Q. 3) Define

### Application of Digital Signature for Securing Communication Using RSA Scheme based on MD5

Application of Digital Signature for Securing Communication Using RSA Scheme based on MD5 Fashoto S.G, Gbadeyan J.A and Okeyinka E.A Redeemer s University, Redemption camp Mowe, Ogun State gbengafash@yahoo.com

### Network Security Technology Network Management

COMPUTER NETWORKS Network Security Technology Network Management Source Encryption E(K,P) Decryption D(K,C) Destination The author of these slides is Dr. Mark Pullen of George Mason University. Permission

### Center for Internet Security. INTEGRATED INTELLIGENCE CENTER Technical White Paper William F. Pelgrin, CIS President and CEO

INTEGRATED INTELLIGENCE CENTER Technical White Paper William F. Pelgrin, CIS President and CEO Private and Public Key Cryptography and Ransomware December 2014 Authored by:ted Fischer (CIS) Security Operations

### Internet and Network Security Fundamentals

Internet and Network Security Fundamentals Presenters Champika Wijayatunga Training Manager, APNIC champika@apnic.net Overview Network Security Basics Security Issues, Threats and Attacks Cryptography

### Secure Socket Layer. Introduction Overview of SSL What SSL is Useful For

Secure Socket Layer Secure Socket Layer Introduction Overview of SSL What SSL is Useful For Introduction Secure Socket Layer (SSL) Industry-standard method for protecting web communications. - Data encryption

### Lecture 6 - Cryptography

Lecture 6 - Cryptography CSE497b - Spring 2007 Introduction Computer and Network Security Professor Jaeger www.cse.psu.edu/~tjaeger/cse497b-s07 Question 2 Setup: Assume you and I don t know anything about

### Cryptosystems. Bob wants to send a message M to Alice. Symmetric ciphers: Bob and Alice both share a secret key, K.

Cryptosystems Bob wants to send a message M to Alice. Symmetric ciphers: Bob and Alice both share a secret key, K. C= E(M, K), Bob sends C Alice receives C, M=D(C,K) Use the same key to decrypt. Public

### A SURVEY ON SECRET KEY ENCRYPTION TECHNIQUE

IMPACT: International Journal of Research in Engineering & Technology (IMPACT: IJRET) ISSN(E): 2321-8843; ISSN(P): 2347-4599 Vol. 2, Issue 5, May 2014, 7-14 Impact Journals A SURVEY ON SECRET KEY ENCRYPTION

### Basics of Cryptography

Basics of Cryptography What is Cryptography? Cryptography is an applied branch of mathematics In some situations it can be used to provide Confidentiality Integrity Authentication Authorization Non-repudiation

### CSCE 465 Computer & Network Security

CSCE 465 Computer & Network Security Instructor: Dr. Guofei Gu http://courses.cse.tamu.edu/guofei/csce465/ Public Key Cryptogrophy 1 Roadmap Introduction RSA Diffie-Hellman Key Exchange Public key and

### Module 8. Network Security. Version 2 CSE IIT, Kharagpur

Module 8 Network Security Lesson 2 Secured Communication Specific Instructional Objectives On completion of this lesson, the student will be able to: State various services needed for secured communication

### 12/3/08. Security in Wireless LANs and Mobile Networks. Wireless Magnifies Exposure Vulnerability. Mobility Makes it Difficult to Establish Trust

Security in Wireless LANs and Mobile Networks Wireless Magnifies Exposure Vulnerability Information going across the wireless link is exposed to anyone within radio range RF may extend beyond a room or

### Public Key Cryptography Overview

Ch.20 Public-Key Cryptography and Message Authentication I will talk about it later in this class Final: Wen (5/13) 1630-1830 HOLM 248» give you a sample exam» Mostly similar to homeworks» no electronic

### AC76/AT76 CRYPTOGRAPHY & NETWORK SECURITY DEC 2014

Q.2a. Define Virus. What are the four phases of Viruses? In addition, list out the types of Viruses. A virus is a piece of software that can infect other programs by modifying them; the modification includes

### 1720 - Forward Secrecy: How to Secure SSL from Attacks by Government Agencies

1720 - Forward Secrecy: How to Secure SSL from Attacks by Government Agencies Dave Corbett Technical Product Manager Implementing Forward Secrecy 1 Agenda Part 1: Introduction Why is Forward Secrecy important?

### Securing Data at Rest ViSolve IT Security Team

Securing Data at Rest ViSolve IT Security Team 1 Table of Contents 1 Introduction... 3 2 Why Data at Rest needs to be secure?... 4 3 Securing Data... 4 3.1 Encryption - Access Control Approach... 5 3.1.1

### Lecture 5 - Cryptography

CSE497b Introduction to Computer and Network Security - Spring 2007 - Professors Jaeger Lecture 5 - Cryptography CSE497b - Spring 2007 Introduction Computer and Network Security Professor Jaeger www.cse.psu.edu/~tjaeger/cse497b-s07/

### Properties of Secure Network Communication

Properties of Secure Network Communication Secrecy: Only the sender and intended receiver should be able to understand the contents of the transmitted message. Because eavesdroppers may intercept the message,

### Introduction to Network Security. 1. Introduction. And People Eager to Take Advantage of the Vulnerabilities

TÜBİTAK Ulusal Elektronik ve Kriptoloji Araştırma Enstitüsü Introduction to Network Security (Revisit an Historical 12 year old Presentation) Prof. Dr. Halûk Gümüşkaya Why Security? Three primary reasons

### SSL A discussion of the Secure Socket Layer

www.harmonysecurity.com info@harmonysecurity.com SSL A discussion of the Secure Socket Layer By Stephen Fewer Contents 1 Introduction 2 2 Encryption Techniques 3 3 Protocol Overview 3 3.1 The SSL Record

### CSE/EE 461 Lecture 23

CSE/EE 461 Lecture 23 Network Security David Wetherall djw@cs.washington.edu Last Time Naming Application Presentation How do we name hosts etc.? Session Transport Network Domain Name System (DNS) Data

### CSCE 465 Computer & Network Security

CSCE 465 Computer & Network Security Instructor: Dr. Guofei Gu http://courses.cse.tamu.edu/guofei/csce465/ Secret Key Cryptography (I) 1 Introductory Remarks Roadmap Feistel Cipher DES AES Introduction

### Discrete logarithms within computer and network security Prof Bill Buchanan, Edinburgh Napier

Discrete logarithms within computer and network security Prof Bill Buchanan, Edinburgh Napier http://asecuritysite.com @billatnapier Introduction. Encryption: Public/Private Key. Key Exchange. Authentication.

### Common Pitfalls in Cryptography for Software Developers. OWASP AppSec Israel July 2006. The OWASP Foundation http://www.owasp.org/

Common Pitfalls in Cryptography for Software Developers OWASP AppSec Israel July 2006 Shay Zalalichin, CISSP AppSec Division Manager, Comsec Consulting shayz@comsecglobal.com Copyright 2006 - The OWASP

### Cryptography Lecture 8. Digital signatures, hash functions

Cryptography Lecture 8 Digital signatures, hash functions A Message Authentication Code is what you get from symmetric cryptography A MAC is used to prevent Eve from creating a new message and inserting

### Application Layer (1)

Application Layer (1) Functionality: providing applications (e-mail, www, USENET etc) providing support protocols to allow the real applications to function properly security comprising a large number

### Application Layer (1)

Application Layer (1) Functionality: providing applications (e-mail, Web service, USENET, ftp etc) providing support protocols to allow the real applications to function properly (e.g. HTTP for Web appl.)

### Cryptography and Network Security Chapter 12

Cryptography and Network Security Chapter 12 Fifth Edition by William Stallings Lecture slides by Lawrie Brown (with edits by RHB) Chapter 12 Message Authentication Codes At cats' green on the Sunday he

### Global Telehealth Conference 2012

A Best Practice Guide to Encryption for Telehealth Liam Caffery PhD Centre for Online Health The University of Queensland Recommendations on best practice Slide 1 of 33 Slide 2 of 33 Introduction Security

### Network Security. Chapter 3 Symmetric Cryptography. Symmetric Encryption. Modes of Encryption. Symmetric Block Ciphers - Modes of Encryption ECB (1)

Chair for Network Architectures and Services Department of Informatics TU München Prof. Carle Network Security Chapter 3 Symmetric Cryptography General Description Modes of ion Data ion Standard (DES)

### Using etoken for SSL Web Authentication. SSL V3.0 Overview

Using etoken for SSL Web Authentication Lesson 12 April 2004 etoken Certification Course SSL V3.0 Overview Secure Sockets Layer protocol, version 3.0 Provides communication privacy over the internet. Prevents

### Lukasz Pater CMMS Administrator and Developer

Lukasz Pater CMMS Administrator and Developer EDMS 1373428 Agenda Introduction Why do we need asymmetric ciphers? One-way functions RSA Cipher Message Integrity Examples Secure Socket Layer Single Sign

### Introduction to Encryption

Computers and Society Introduction to Encryption Chris Brooks Department of Computer Science University of San Francisco Department of Computer Science University of San Francisco p.1/35 3-0: Terminology

### Evaluation of the RC4 Algorithm for Data Encryption

Evaluation of the RC4 Algorithm for Data Encryption Allam Mousa (1) and Ahmad Hamad (2) (1) Electrical Engineering Department An-Najah University, Nablus, Palestine (2) Systems Engineer PalTel Company,

### CPS 590.5 Computer Security Lecture 9: Introduction to Network Security. Xiaowei Yang xwy@cs.duke.edu

CPS 590.5 Computer Security Lecture 9: Introduction to Network Security Xiaowei Yang xwy@cs.duke.edu Previous lectures Worm Fast worm design Today Network security Cryptography building blocks Existing

### Secure Sockets Layer (SSL ) / Transport Layer Security (TLS) Network Security Products S31213

Secure Sockets Layer (SSL ) / Transport Layer Security (TLS) Network Security Products S31213 UNCLASSIFIED Example http ://www. greatstuf f. com Wants credit card number ^ Look at lock on browser Use https

### Security. Friends and Enemies. Overview Plaintext Cryptography functions. Secret Key (DES) Symmetric Key

Friends and Enemies Security Outline Encryption lgorithms Protocols Message Integrity Protocols Key Distribution Firewalls Figure 7.1 goes here ob, lice want to communicate securely Trudy, the intruder

### ECE 428 Network Security

ECE 428 Network Security 1 Learning objectives Security requirements and tools Symmetric-key (secret key) cryptography Substitution, transposition, and product ciphers (DES) Public key cryptography: RSA

### A Standards-based Approach to IP Protection for HDLs

A Standards-based Approach to IP Protection for HDLs John Shields Staff Engineer, Modelsim Overview Introduction A Brief Status First Look at The Flow Encryption Technology Concepts Key Management Second

### Overview of Public-Key Cryptography

CS 361S Overview of Public-Key Cryptography Vitaly Shmatikov slide 1 Reading Assignment Kaufman 6.1-6 slide 2 Public-Key Cryptography public key public key? private key Alice Bob Given: Everybody knows

### Network Security [2] Plain text Encryption algorithm Public and private key pair Cipher text Decryption algorithm. See next slide

Network Security [2] Public Key Encryption Also used in message authentication & key distribution Based on mathematical algorithms, not only on operations over bit patterns (as conventional) => much overhead

### 7 Network Security. 7.1 Introduction 7.2 Improving the Security 7.3 Internet Security Framework. 7.5 Absolute Security?

7 Network Security 7.1 Introduction 7.2 Improving the Security 7.3 Internet Security Framework 7.4 Firewalls 7.5 Absolute Security? 7.1 Introduction Security of Communications data transport e.g. risk

### Cryptography and Network Security Department of Computer Science and Engineering Indian Institute of Technology Kharagpur

Cryptography and Network Security Department of Computer Science and Engineering Indian Institute of Technology Kharagpur Module No. # 01 Lecture No. # 05 Classic Cryptosystems (Refer Slide Time: 00:42)

### Introduction to Cryptography

Introduction to Cryptography Part 3: real world applications Jean-Sébastien Coron January 2007 Public-key encryption BOB ALICE Insecure M E C C D channel M Alice s public-key Alice s private-key Authentication

### Security for Computer Networks

Security for Computer Networks An Introduction to Data Security in Teleprocessing and Electronic Funds Transfer D. W. Davies Consultant for Data Security and W. L. Price National Physical Laboratory, Teddington,

### CS3235 - Computer Security Third topic: Crypto Support Sys

Systems used with cryptography CS3235 - Computer Security Third topic: Crypto Support Systems National University of Singapore School of Computing (Some slides drawn from Lawrie Brown s, with permission)