Network Security Chapter 8 8.3 - 8.6. Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011.

Slides:

Advertisements

Similar presentations

Chapter 3 Public Key Cryptography and Message authentication.

Advertisements

Hash Functions A hash function takes data of arbitrary size and returns a value in a fixed range. If you compute the hash of the same data at different.

Spring 2000CS 4611 Security Outline Encryption Algorithms Authentication Protocols Message Integrity Protocols Key Distribution Firewalls.

Crypto – chapter 16 - noack Introduction to network stcurity Chapter 16 - Stallings.

Network Security Chapter 8. Cryptography Introduction to Cryptography Substitution Ciphers Transposition Ciphers One-Time Pads Two Fundamental Cryptographic.

EEC 693/793 Special Topics in Electrical Engineering Secure and Dependable Computing Lecture 6 Wenbing Zhao Department of Electrical and Computer Engineering.

EEC 693/793 Special Topics in Electrical Engineering Secure and Dependable Computing Lecture 6 Wenbing Zhao Department of Electrical and Computer Engineering.

Dr Alejandra Flores-Mosri Message Authentication Internet Management & Security 06 Learning outcomes At the end of this session, you should be able to:

BY MUKTADIUR RAHMAN MAY 06, 2010 INTERODUCTION TO CRYPTOGRAPHY.

Cryptographic Technologies

Kemal AkkayaWireless & Network Security 1 Department of Computer Science Southern Illinois University Carbondale CS 591 – Wireless & Network Security Lecture.

Henric Johnson1 Chapter3 Public-Key Cryptography and Message Authentication Henric Johnson Blekinge Institute of Technology, Sweden

Secure Hashing and DSS Sultan Almuhammadi ICS 454 Principles of Cryptography.

EEC-484/584 Computer Networks Lecture 16 Wenbing Zhao

Network Security Chapter 8. Cryptography Introduction to Cryptography Substitution Ciphers Transposition Ciphers One-Time Pads Two Fundamental Cryptographic.

EEC-484/584 Computer Networks Lecture 16 Wenbing Zhao

EEC-484/584 Computer Networks Lecture 18 Wenbing Zhao (Part of the slides are based on materials supplied by Prentice-Hall)

Chapter 3 Encryption Algorithms & Systems (Part C)

TCP/IP Protocol Suite 1 Chapter 28 Upon completion you will be able to: Security Differentiate between two categories of cryptography schemes Understand.

Chapter 8 Network Security 4/17/2017

Network Security. Contents Security Requirements and Attacks Confidentiality with Conventional Encryption Message Authentication and Hash Functions Public-Key.

Network Security Chapter

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Network Security Chapter 8.

CSE 597E Fall 2001 PennState University1 Digital Signature Schemes Presented By: Munaiza Matin.

1 Public-Key Cryptography and Message Authentication Ola Flygt Växjö University, Sweden

Bob can sign a message using a digital signature generation algorithm

Lecture 15 Lecture’s outline Public algorithms (usually) that are each other’s inverse.

Network Security Chapter 8

1 ECE453 – Introduction to Computer Networks Lecture 19 – Network Security (II)

Computer Networks NYUS FCSIT Spring 2008 Milos STOLIC, Bs.C. Teaching Assistant

EEC 688/788 Secure and Dependable Computing

Network Security. An Introduction to Cryptography The encryption model (for a symmetric-key cipher).

ECE453 – Introduction to Computer Networks Lecture 18 – Network Security (I)

Chi-Cheng Lin, Winona State University CS 313 Introduction to Computer Networking & Telecommunication Network Security (A Very Brief Introduction)

Information Security Principles Assistant Professor Dr. Sana’a Wafa Al-Sayegh 1 st Semester ITGD 2202 University of Palestine.

Network Security. Information secrecy-only specified parties know the information exchanged. Provided by criptography. Information integrity-the information.

Network Security. Cryptography Cryptography functions Secret key (e.g., DES) Public key (e.g., RSA) Message digest (e.g., MD5) Security services Privacy:

Public Key, Digital Signatures, Management and Security.

ECE509 Cyber Security : Concept, Theory, and Practice Cryptography Spring 2014.

©The McGraw-Hill Companies, Inc., 2000© Adapted for use at JMU by Mohamed Aboutabl, 2003Mohamed Aboutabl1 1 Chapter 29 Internet Security.

4 th lecture.  Message to be encrypted: HELLO  Key: XMCKL H E L L O message 7 (H) 4 (E) 11 (L) 11 (L) 14 (O) message + 23 (X) 12 (M) 2 (C) 10 (K) 11.

Chapter 21 Public-Key Cryptography and Message Authentication.

1 Public-Key Cryptography and Message Authentication.

Cryptography and Network Security Chapter 13 Fifth Edition by William Stallings Lecture slides by Lawrie Brown.

Cryptography and Network Security Chapter 9 - Public-Key Cryptography

Network Security David Lazăr.

Tanenbaum & Van Steen, Distributed Systems: Principles and Paradigms, 2e, (c) 2007 Prentice-Hall, Inc. All rights reserved DISTRIBUTED.

4-Jun-164/598N: Computer Networks Differentiated Services Problem with IntServ: scalability Idea: segregate packets into a small number of classes –e.g.,

Information and Network Security Rudra Dutta CSC 401- Fall 2011, Section 001.

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Chapter 14 Network Security: Firewalls and VPNs.

Security Many secure IT systems are like a house with a locked front door but with a side window open -somebody.

Section 3: Public Key, Digital Signature

Cryptography: Digital Signatures Message Digests Authentication

McGraw-Hill©The McGraw-Hill Companies, Inc., 2000 Chapter 29 Internet Security.

Chapter 3 – Public Key Cryptography and RSA (A). Private-Key Cryptography traditional private/secret/single-key cryptography uses one key shared by both.

Network Security Chapter 8 12/13/ Cryptography Introduction to Cryptography Substitution Ciphers Transposition Ciphers One-Time Pads Two Fundamental.

Fall, Privacy&Security - Virginia Tech – Computer Science Click to edit Master title style Cryptographic Security Identity-Based Encryption.

Computer and Network Security - Message Digests, Kerberos, PKI –

Group 9 Chapter 8.3 – 8.6. Public Key Algorithms  Symmetric Key Algorithms face an inherent problem  Keys must be distributed to all parties but kept.

EEC 688/788 Secure and Dependable Computing Lecture 4 Wenbing Zhao Department of Electrical and Computer Engineering Cleveland State University

EEC 688/788 Secure and Dependable Computing Lecture 4 Wenbing Zhao Department of Electrical and Computer Engineering Cleveland State University

Cryptography and Network Security Third Edition by William Stallings Lecture slides by Lawrie Brown.

ECE Prof. John A. Copeland fax Office: GCATT Bldg.

Network Security Chapter 8 Institute of Information Science and Technology. Chengdu University YiYong 2008 年 2 月 25 日.

Chapter 8 Network Security.

Network Security Chapter 8

Chapter 8 Network Security.

Public-Key, Digital Signatures, Management, Security

Chapter 3 - Public-Key Cryptography & Authentication

Network Security Chapter 8.

Presentation transcript:

Network Security Chapter

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Public-key Algorithms RSA –Authors: Rivest, Shamir, Adleman Other Public-Key Algorithms

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 RSA (1) Method Summary 1. Choose two large primes, p and q 2. Compute n = p × q and z = ( p − 1) × (q − 1). 3. Choose number relatively prime to z call it d. 4. Find e such that e × d = 1 mod z.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 RSA (2) An example of the RSA algorithm

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Digital Signatures (1) Required Conditions: 1. Receiver can verify claimed identity of sender. 2. Sender cannot later repudiate contents of message. 3. Receiver cannot have concocted message himself.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Digital Signatures (2) Symmetric-key signatures Public-key signatures Message digests The birthday attack

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Symmetric-key Signatures Digital signatures with Big Brother

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Public-Key Signatures (1) Digital signatures using public-key cryptography.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Public-Key Signatures (2) Criticisms of DSS: 1. Too secret 2. Too slow 3. Too new 4. Too insecure

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Message Digests (1) Message Digest properties 1. Given P, easy to compute MD(P). 2. Given MD(P), effectively impossible to find P. 3. Given P no one can find P′ such that MD(P′) = MD(P). 4. Change to input of even 1 bit produces very different output.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Message Digests (2) Digital signatures using message digests

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Message Digests (3) Use of SHA-1 and RSA for signing nonsecret messages

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Message Digests (4) (a) A message padded out to a multiple of 512 bits. (b) The output variables. (c) The word array.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Management of Public Keys (1) A way for Trudy to subvert public-key encryption

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Management of Public Keys (2) Certificates X.509 Public key infrastructures

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Certificates A possible certificate and its signed hash

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 X.509 The basic fields of an X.509 certificate

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Public Key Infrastructures (a) A hierarchical PKI. (b) A chain of certificates.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Communication Security IPsec Firewalls Virtual private networks Wireless security

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 IPsec (1) The IPsec authentication header in transport mode for IPv4.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 IPsec (2) (a) ESP in transport mode. (b) ESP in tunnel mode.

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 IPsec (3) A firewall protecting an internal network

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Virtual Private Networks (1) A virtual private network

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Virtual Private Networks (2) Topology as seen from the inside

Computer Networks, Fifth Edition by Andrew Tanenbaum and David Wetherall, © Pearson Education-Prentice Hall, 2011 Wireless Security The i key setup handshake