Introduction to Security
|
|
- Martin Farmer
- 6 years ago
- Views:
Transcription
1 Introduction to Security Avinanta Tarigan Universitas Gunadarma 1 Avinanta Tarigan Introduction to Security
2 Layout Problems General Security Cryptography & Protocol reviewed 2 Avinanta Tarigan Introduction to Security
3 Problems Life was beautiful before computer, getting worse after Internet Distributed systems: each depends on others How can we assure system behaves correctly & securely? Can we trust systems on the other side? 3 Avinanta Tarigan Introduction to Security
4 Problems.. (cont) How to assure security of the network How to quantify risk What are the boundaries of the system? Relationship to political, social, enomical aspects is not well understood Uncertainty 4 Avinanta Tarigan Introduction to Security
5 Definition In General : Computer Security deals with the method against unauthorized actions in computer systems More General : Dependability to other institution is also insecurity 5 Avinanta Tarigan Introduction to Security
6 Basic 6 Avinanta Tarigan Introduction to Security
7 Basic 7 Avinanta Tarigan Introduction to Security
8 Basic State (Keadaan) * Unauthorized Access (Cracked) * Sensible Information Sniffed Vulnerability (Kelemahan) * Password Stolen * Unauthenticated Sites Security Violation (Pelanggaran) Attacker who attacks State Transition 8 Avinanta Tarigan Introduction to Security
9 What is secure? Computer based system behaves according to 1 algorithms (program/software) 2 user direction (input) Given systems & environment: 1 secure states (system maintains security properties) 2 insecure states (violation of security policy) 3 paths lead to insecure states (vulnerability) Correctness: maintain intended behavior according to correct specification while unintended behavior will not be reachable Security policy: definition of (1,2,3) Attack : Persistence, Intentional, Outsider vs Insider, Loss vs Gain 9 Avinanta Tarigan Introduction to Security
10 Threats... (cont) Towards vulnerable system [Abadi] : Interaction with uncertain physical, network, software environment. Using public network, distributed administration, diverse operators COTS, business demand is the priority, Monocultures 10 Avinanta Tarigan Introduction to Security
11 Threats... (cont) Attack : Physical attack ex. theft of harddisk/cdroms, bombing, etc. Syntatic attack ex. buffer overflow, domain theft, SQL injection Semantic attack ex. Social engineering, site phising 11 Avinanta Tarigan Introduction to Security
12 Security Policy We define secure states and insecure states Define paths which always bring system in secure states: what is permited Define also paths might lead to insecure states: what is not allowed Specified in formal language for clearness, unambiguity, consistency, and verificability Written in natural language for better understanding 12 Avinanta Tarigan Introduction to Security
13 Properties Confidentiality (Secrecy) Unauthorized disclosure of information is not reachable (Acces Control - Cryptography) Integrity Unauthorized modification of information is not reachable Data integrity - Origin integrity / authentication Prevention (access control) - Detection (hash function) 13 Avinanta Tarigan Introduction to Security
14 Properties... (cont) Availability Prevention & detection of denial of service Accountability The availablity and completeness of the track of past system states Who - Whom - What - When - Where Implementation: should be forensic ready 14 Avinanta Tarigan Introduction to Security
15 Goals Prevention to fail the attack Detection to detect unprevented attack Recovery to stop the attack & repair attacked system 15 Avinanta Tarigan Introduction to Security
16 Security Mechanism Way to enforce security policies How to limit system behavior according to policies Specification - Design - Implementation - Operation & Maintenance - Audit (Forensic) Access Control & Cryptography 16 Avinanta Tarigan Introduction to Security
17 Access Control Reference Monitor Set of precise rules according to security policy, applied as a filter to the transition states of the system, which prevents system in entering insecure state Authentication is mandatory Subjects, Objects, Actions, Time, Location, and other attributes 17 Avinanta Tarigan Introduction to Security
18 Model of Acces Control Mandatory Access Control (MAC) Top Secret Obj N Discretionary Access Control (DAC) Role Based Access Control (RBAC) Obj 1 Obj 2 Obj N Obj 1 Obj 2 Obj N Safe Dealing (SD) Obj 1 Obj 2 Obj N Secret Confident Obj 1 Obj 2 Attribute Control Ticket K Ticket K Ticket K Enrollment Subj 1 Subj 2 Subj N Subj 1 Subj 2 Subj N Subj 1 Subj 2 Subj N Subj 1 Subj 2 Subj N 18 Avinanta Tarigan Introduction to Security
19 Implementation: Cryptography Algorithm to protect secrecy of data Also used to gain : authentication integrity non repudiation Includes : algorithm and key(s) 19 Avinanta Tarigan Introduction to Security
20 Cryptography... (cont) Chipertext = Encrypt(Message, Key) Message = Decrypt(Chipertext, Key) Decrypt(Chipertext) hard without Key Research questions : Is there any algorithm which is hard to compute original message but easy to verify it In implementation requires a protocol (Cryptographic Protocol) 20 Avinanta Tarigan Introduction to Security
21 Symmetric Crypt. A B : {M } Kab Principal A sends B message M encrypted with shared-key K ab Key is shared between 2 principals Needs N 2 keys for N principals Fast but key management is not easy Example of Chiper: DES, 3DES, Blowfish, AES 21 Avinanta Tarigan Introduction to Security
22 Asymmetric/Public Key Crypt. A B : {M } Kb Principal A sends B message M encrypted with B s public-key K b Only with private-key K 1, B can decrypt M b Principal has its own K which is published and K 1 which must be keeped secret Key management is less difficult, usualy managed by Certification Authority Example of Chiper: RSA (Rivest-Shamir-Addleman), Elliptic-Curve 22 Avinanta Tarigan Introduction to Security
23 One-Way-Hash Algorithm to compute large data into small integer, producing fingerprint of the message Used for maintaining integrity of message being transferred Example: MD5, SHA1, SHA-256, Ripemd, Haval 23 Avinanta Tarigan Introduction to Security
24 Digital Signature (Sign) 24 Avinanta Tarigan Introduction to Security
25 Digital Signature (Verify) 25 Avinanta Tarigan Introduction to Security
26 Digital Signature A B : {M,{Hash(M )} Ka } Kb A s digital signature on a message is the hash of message encrypted with A s private-key Authentication: only with A s public-key, the hash can be decrypted Integrity: Hash function Confidentiality: message can be decrypted only with B s private-key Non-Repudiation: explain for your self 26 Avinanta Tarigan Introduction to Security
27 Pictures of Cryptographer 27 Avinanta Tarigan Introduction to Security
28 Cryptographic Protocol Implementation of Cryptography Algorithm Achieving security properties (authentication, secrecy, etc.) Example : Needham-Schroeder (authentication) Kerberos (authentication) SSL/TLS (auth - secrecy) 28 Avinanta Tarigan Introduction to Security
29 Cryptographic Protocol Example : Needham-Schroeder Protocol M1 M2 M3 M4 M5 A S : A, B, N a S A : {N a, B, K ab, {K ab, A}K bs }K as A B : {K ab, A}K bs B A : {N b }K ab A B : {N b 1}K ab Intoducing Nonce (N) 29 Avinanta Tarigan Introduction to Security
30 Cryptographic Protocol More example : Kerberos Protocol M1 M2 M3 M4 A S : A, B S A : {T s, L, B, K ab, {T s, L, K ab, A}K bs }K as A B : {T s, L, K ab, A}K bs, {A, T a }K ab B A : {T a + 1}K ab Introducing TimeStamp (T ) and Lifetime (L) Used in many system, including Windows 30 Avinanta Tarigan Introduction to Security
31 Cryptographic Protocol Problem : Wrong design could lead to flaw Needham-Schroeder Protocol SSLv1.0 Wrong implementation could lead to vulnerability Padding problem in SSL, SSH, and WTLS User Interface design in Browser Vulnerability arise between two protection technologies (Anderson, Ross) 31 Avinanta Tarigan Introduction to Security
32 Assurance : Formal Method To prove correctness in achieving security properties which protocol carry out There are two development approach : Extention from method used in communication Newly developed method Four classifications : 1. General purpose tools 3. Expert System 2. Logic based 4. Algebraic approach 32 Avinanta Tarigan Introduction to Security
33 Formal Method Using General Purpose Tools Treated as ordinary comm. protocol Adversary is explicit, capable in read, intercept, and modify messages Method : FSM, CSP, FDR, Petri Nets Example : Lotos, Ina Jo, Murphy System State A INTRUDER B 33 Avinanta Tarigan Introduction to Security
34 Formal Method Using Expert System Investigate every possible scenario of Attack - Flaw - Defence Needs to define insecure states and search paths to them More successful than General Purpose Tools Example : Interrogator by Millen, NRL Protocol Analyzer by Meadows, Longley and Rigby 34 Avinanta Tarigan Introduction to Security
35 Formal Method Algebraic Approach Capabilties in modeling knowledge which represents component in cryptographic operation (Nonce, Key(s), and old messages) Example : Dolev - Yao (term re-writing systems) Sphi - Calculus by Abadi and Gordon (to prove secrecy) 35 Avinanta Tarigan Introduction to Security
36 Formal Method Logic Based One sees crypt. protocol as distributed algorithm Develop logics from modal logic There are inference rules Goal is to derived statements which represents correct condition Example : BAN Logic and GNY Logic 36 Avinanta Tarigan Introduction to Security
37 Towards Secure System Specification : Security Policy Implementation : Security Mechanism Correctness : Assurance Man - Machine - Management 37 Avinanta Tarigan Introduction to Security
38 Towards... (cont) Preventive measures Detective measures Responsive measures Desktop Servers Perimeter Managers General Users Security Team 38 Avinanta Tarigan Introduction to Security
39 Towards.. (cont) Security Goals Constituent OrganizationalUnits Availability Integrity Confidentiality Non Repudiation etc Government Agent Financial Institutions Organizations Local etc Policy User Education Secure OS, Application, Perimeter etc Constituent Systems 39 Avinanta Tarigan Introduction to Security
40 Books, Papers, and Links Ross Anderson, Security Engineering Matt Bishop, Computer Security Schneider et. al. Modelling and Analysis of Security Protocols Martin Abadi s homepage at abadi 40 Avinanta Tarigan Introduction to Security
41 The End End of this presentation 41 Avinanta Tarigan Introduction to Security
Lecture 15: Cryptographic algorithms
06-06798 Distributed Systems Lecture 15: Cryptographic algorithms 22 March, 2002 1 Overview Cryptographic algorithms symmetric: TEA asymmetric: RSA Digital signatures digital signatures with public key
More information1.264 Lecture 27. Security protocols Symmetric cryptography. Next class: Anderson chapter 10. Exercise due after class
1.264 Lecture 27 Security protocols Symmetric cryptography Next class: Anderson chapter 10. Exercise due after class 1 Exercise: hotel keys What is the protocol? What attacks are possible? Copy Cut and
More informationLecture 19: cryptographic algorithms
Lecture 19: cryptographic algorithms Operating Systems and Networks Behzad Bordbar School of Computer Science, University of Birmingham, UK 179 Overview Cryptographic algorithms symmetric: TEA asymmetric:
More informationElements of Security
Elements of Security Dr. Bill Young Department of Computer Sciences University of Texas at Austin Last updated: April 8, 2015 at 12:47 Slideset 7: 1 Car Talk Puzzler You have a friend in a police state
More informationFrom Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design. Edition 4 Pearson Education 2005
Chapter 7: Security From Coulouris, Dollimore and Kindberg Distributed Systems: Concepts and Design Edition 4 Introduction Security policies Provide for the sharing of resources within specified limits
More informationDigital Signatures. Secure Digest Functions
Digital Signatures Secure Digest Functions 8 requirements for one-way hash functions given M, H(M) is easy to compute given H(M), M is difficult to compute given M, it is difficult to find M such that
More informationSession key establishment protocols
our task is to program a computer which gives answers which are subtly and maliciously wrong at the most inconvenient possible moment. -- Ross Anderson and Roger Needham, Programming Satan s computer Session
More informationProtocols II. Computer Security Lecture 12. David Aspinall. 17th February School of Informatics University of Edinburgh
Protocols II Computer Security Lecture 12 David Aspinall School of Informatics University of Edinburgh 17th February 2011 Outline Introduction Shared-key Authentication Asymmetric authentication protocols
More informationLecture 1: Course Introduction
Lecture 1: Course Introduction Thomas Johansson T. Johansson (Lund University) 1 / 37 Chapter 9: Symmetric Key Distribution To understand the problems associated with managing and distributing secret keys.
More informationSession key establishment protocols
our task is to program a computer which gives answers which are subtly and maliciously wrong at the most inconvenient possible moment. -- Ross Anderson and Roger Needham, Programming Satan s computer Session
More information(2½ hours) Total Marks: 75
(2½ hours) Total Marks: 75 N. B.: (1) All questions are compulsory. (2) Makesuitable assumptions wherever necessary and state the assumptions made. (3) Answers to the same question must be written together.
More informationCUNY John Jay College of Criminal Justice MATH AND COMPUTER SCIENCE
Instructor: Prof Aftab Ahmad Office: NB 612 Telephone No. (212)393-6314 Email Address: aahmad@jjay.cuny.edu Office Hours: By appointment TEXT & REFERENCE MATERIAL Text Notes from instructor posted on Blackboard
More informationModule: Cryptographic Protocols. Professor Patrick McDaniel Spring CMPSC443 - Introduction to Computer and Network Security
CMPSC443 - Introduction to Computer and Network Security Module: Cryptographic Protocols Professor Patrick McDaniel Spring 2009 1 Key Distribution/Agreement Key Distribution is the process where we assign
More informationCS 470 Spring Security. Mike Lam, Professor. a.k.a. Why on earth do Alice and Bob need to talk so much?!? Content taken from the following:
50fb6be35f4c3105 9d4ed08fb86d8887 b746c452a9c9443b 15b22f450c76218e CS 470 Spring 2017 9df7031cdbff9d10 b700a92855f16328 5b757e66d2131841 62fedd7d9131e42e Mike Lam, Professor Security a.k.a. Why on earth
More informationKALASALINGAM UNIVERSITY
KALASALINGAM UNIVERSITY (Kalasalingam Academy of Research and Education) DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING CLASS NOTES CRYPTOGRAPHY AND NETWOTK SECURITY (CSE 405) Prepared by M.RAJA AP/CSE
More informationCompTIA Security+ (Exam SY0-401) Course 01 Security Fundamentals
CompTIA Security+ (Exam SY0-401) Course 01 Security Fundamentals This course contains copyrighted material used by permission of Logical Operations, Inc. Slide 1 Course 01: Security Fundamentals The Information
More informationCryptographic Protocols 1
Cryptographic Protocols 1 Luke Anderson luke@lukeanderson.com.au 5 th May 2017 University Of Sydney Overview 1. Crypto-Bulletin 2. Problem with Diffie-Hellman 2.1 Session Hijacking 2.2 Encrypted Key Exchange
More informationModelling and Analysing of Security Protocol: Lecture 1. Introductions to Modelling Protocols. Tom Chothia CWI
Modelling and Analysing of Security Protocol: Lecture 1 Introductions to Modelling Protocols Tom Chothia CWI This Course This course will primarily teaching you: How to design your own secure communication
More informationCompTIA Security+ (2008 Edition) Exam
CompTIA SY0-201 CompTIA Security+ (2008 Edition) Exam Version: 7.20 Topic 1, Volume A QUESTION NO: 1 Which of the following cryptography types provides the same level of security but uses smaller key sizes
More informationData Security and Privacy. Topic 14: Authentication and Key Establishment
Data Security and Privacy Topic 14: Authentication and Key Establishment 1 Announcements Mid-term Exam Tuesday March 6, during class 2 Need for Key Establishment Encrypt K (M) C = Encrypt K (M) M = Decrypt
More informationOutline More Security Protocols CS 239 Computer Security February 6, 2006
Outline More Security Protocols CS 239 Computer Security February 6, 2006 Combining key distribution and authentication Verifying security protocols Page 1 Page 2 Combined Key Distribution and Authentication
More informationComputer Networks & Security 2016/2017
Computer Networks & Security 2016/2017 Network Security Protocols (10) Dr. Tanir Ozcelebi Courtesy: Jerry den Hartog Courtesy: Kurose and Ross TU/e Computer Science Security and Embedded Networked Systems
More informationSecurity: Focus of Control. Authentication
Security: Focus of Control Three approaches for protection against security threats a) Protection against invalid operations b) Protection against unauthorized invocations c) Protection against unauthorized
More informationVerteilte Systeme (Distributed Systems)
Verteilte Systeme (Distributed Systems) Lorenz Froihofer l.froihofer@infosys.tuwien.ac.at http://www.infosys.tuwien.ac.at/teaching/courses/ VerteilteSysteme/ Security Threats, mechanisms, design issues
More informationGrenzen der Kryptographie
Microsoft Research Grenzen der Kryptographie Dieter Gollmann Microsoft Research 1 Summary Crypto does not solve security problems Crypto transforms security problems Typically, the new problems relate
More informationOutline. More Security Protocols CS 239 Security for System Software April 22, Needham-Schroeder Key Exchange
Outline More Security Protocols CS 239 Security for System Software April 22, 2002 Combining key distribution and authentication Verifying security protocols Page 1 Page 2 Combined Key Distribution and
More informationSecurity: Focus of Control
Security: Focus of Control Three approaches for protection against security threats a) Protection against invalid operations b) Protection against unauthorized invocations c) Protection against unauthorized
More informationTestpassport http://www.testpassport.net Exam : SY0-301 Title : Security+ Certification Exam 2011 version Version : Demo 1 / 5 1.Which of the following is the BEST approach to perform risk mitigation of
More informationCryptography & Key Exchange Protocols. Faculty of Computer Science & Engineering HCMC University of Technology
Cryptography & Key Exchange Protocols Faculty of Computer Science & Engineering HCMC University of Technology Outline 1 Cryptography-related concepts 2 3 4 5 6 7 Key channel for symmetric cryptosystems
More informationPASS4TEST. IT Certification Guaranteed, The Easy Way! We offer free update service for one year
PASS4TEST \ http://www.pass4test.com We offer free update service for one year Exam : SY0-301 Title : CompTIA Security+ Certification Exam (SY0-301) Vendor : CompTIA Version : DEMO 1 / 5 Get Latest & Valid
More information06/02/ Local & Metropolitan Area Networks. 0. Overview. Terminology ACOE322. Lecture 8 Network Security
1 Local & Metropolitan Area Networks ACOE322 Lecture 8 Network Security Dr. L. Christofi 1 0. Overview As the knowledge of computer networking and protocols has become more widespread, so the threat of
More information19.1. Security must consider external environment of the system, and protect it from:
Module 19: Security The Security Problem Authentication Program Threats System Threats Securing Systems Intrusion Detection Encryption Windows NT 19.1 The Security Problem Security must consider external
More informationIntroduction and Overview. Why CSCI 454/554?
Introduction and Overview CSCI 454/554 Why CSCI 454/554? Get Credits and Graduate Security is important More job opportunities More research funds 1 Workload Five homework assignments Two exams (open book
More informationCS 470 Spring Security. Mike Lam, Professor. a.k.a. Why on earth do Alice and Bob need to share so many secrets?!?
50fb6be35f4c3105 9d4ed08fb86d8887 b746c452a9c9443b 15b22f450c76218e CS 470 Spring 2018 9df7031cdbff9d10 b700a92855f16328 5b757e66d2131841 62fedd7d9131e42e Mike Lam, Professor Security a.k.a. Why on earth
More informationPresented by Jack G. Nestell. Topics for Discussion. I. Introduction. Discussion on the different logics and methods of reasonings of Formal Methods
A Discussion on Security Protocols over open networks and distributed Systems: Formal methods for their Analysis, Design, and Verification S. Gritzalis, D. Spinellis, and P. Georgiadis Presented by Jack
More informationSecurity and Privacy in Computer Systems. Lecture 7 The Kerberos authentication system. Security policy, security models, trust Access control models
CS 645 Security and Privacy in Computer Systems Lecture 7 The Kerberos authentication system Last Week Security policy, security models, trust Access control models The Bell-La Padula (BLP) model The Biba
More informationCristina Nita-Rotaru. CS355: Cryptography. Lecture 17: X509. PGP. Authentication protocols. Key establishment.
CS355: Cryptography Lecture 17: X509. PGP. Authentication protocols. Key establishment. Public Keys and Trust Public Key:P A Secret key: S A Public Key:P B Secret key: S B How are public keys stored How
More informationFormal Methods for Security Protocols
Role of Temur.Kutsia@risc.uni-linz.ac.at Formal Methods Seminar January 26, 2005 Role of Outline 1 Role of 2 Security Properties Attacker Models Keys Symmetric and Asymmetric Systems 3 Notation and Examples
More informationInformation Security: Principles and Practice Second Edition. Mark Stamp
Information Security: Principles and Practice Second Edition Mark Stamp August 10, 2009 Contents Preface Second Edition Preface About The Author Acknowledgments xvii xix xxiii xxv 1 Introduction 1 1.1
More informationOutline More Security Protocols CS 239 Computer Security February 4, 2004
Outline More Security Protocols CS 239 Computer Security February 4, 2004 Combining key distribution and authentication Verifying security protocols Page 1 Page 2 Combined Key Distribution and Authentication
More informationCRYPTOGRAPHY AND NETWROK SECURITY-QUESTION BANK
CRYPTOGRAPHY AND NETWROK SECURITY-QUESTION BANK UNIT-1 1. Answer the following: a. What is Non-repudiation b. Distinguish between stream and block ciphers c. List out the problems of one time pad d. Define
More informationACS / Computer Security And Privacy. Fall 2018 Mid-Term Review
ACS-3921-001/4921-001 Computer Security And Privacy Fall 2018 Mid-Term Review ACS-3921/4921-001 Slides Used In The Course A note on the use of these slides: These slides has been adopted and/or modified
More informationImplementing Cryptography: Good Theory vs. Bad Practice
Implementing Cryptography: Good Theory vs. Bad Practice Viet Pham Information Security Group, Department of Mathematics Royal Holloway, University of London Outline News report What is cryptography? Why
More informationSecurity protocols and their verification. Mark Ryan University of Birmingham
Security protocols and their verification Mark Ryan University of Birmingham Contents 1. Authentication protocols (this lecture) 2. Electronic voting protocols 3. Fair exchange protocols 4. Digital cash
More informationNetwork Security. Chapter 8. MYcsvtu Notes.
Network Security Chapter 8 Network Security Some people who cause security problems and why. Cryptography Introduction Substitution ciphers Transposition ciphers One-time pads Fundamental cryptographic
More informationCombined CPV-TLV Security Protocol Verifier
Combined CPV-TLV Security Protocol Verifier by Ariel Cohen Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science Department of Computer Science Courant Institute
More informationIssues. Separation of. Distributed system security. Security services. Security policies. Security mechanism
Module 9 - Security Issues Separation of Security policies Precise definition of which entities in the system can take what actions Security mechanism Means of enforcing that policy Distributed system
More informationSecurity Handshake Pitfalls
Hello Challenge R f(k, R f(k, R Problems: 1. Authentication is not mutual only authenticates Anyone can send the challenge R. f(k, R Problems: 1. Authentication is not mutual only authenticates Anyone
More informationSecurity. Alessandro Margara Slides based on previous work by Matteo Migliavacca and Alessandro Sivieri
Security Alessandro Margara alessandro.margara@polimi.it Slides based on previous work by Matteo Migliavacca and Alessandro Sivieri Why security in a DS course? Sharing of resources is the motivating factor
More informationDistributed Systems. Lecture 14: Security. Distributed Systems 1
06-06798 Distributed Systems Lecture 14: Security Distributed Systems 1 What is security? policies and mechanisms threats and attacks Overview Security of electronic transactions secure channels authentication
More informationMechanising BAN Kerberos by the Inductive Method
Mechanising BAN Kerberos by the Inductive Method Giampaolo Bella Lawrence C Paulson Computer Laboratory University of Cambridge New Museums Site, Pembroke Street Cambridge CB2 3QG (UK) {gb221,lcp}@cl.cam.ac.uk
More information1.264 Lecture 28. Cryptography: Asymmetric keys
1.264 Lecture 28 Cryptography: Asymmetric keys Next class: Anderson chapters 20. Exercise due before class (Reading doesn t cover same topics as lecture) 1 Asymmetric or public key encryption Receiver
More informationAuthentication Handshakes
AIT 682: Network and Systems Security Topic 6.2 Authentication Protocols Instructor: Dr. Kun Sun Authentication Handshakes Secure communication almost always includes an initial authentication handshake.
More informationDigital Signatures. Public-Key Signatures. Arbitrated Signatures. Digital Signatures With Encryption. Terminology. Message Authentication Code (MAC)
Message Authentication Code (MAC) Key-dependent one-way hash function Only someone with a correct key can verify the hash value Easy way to turn one-way hash function into MAC is to encrypt hash value
More informationTransport Layer Security
CEN585 Computer and Network Security Transport Layer Security Dr. Mostafa Dahshan Department of Computer Engineering College of Computer and Information Sciences King Saud University mdahshan@ksu.edu.sa
More informationDistributed Systems. Lecture 14: Security. 5 March,
06-06798 Distributed Systems Lecture 14: Security 5 March, 2002 1 What is security? policies and mechanisms threats and attacks Overview Security of electronic transactions secure channels authentication
More informationSecurity Handshake Pitfalls
Security Handshake Pitfalls Ahmet Burak Can Hacettepe University abc@hacettepe.edu.tr 1 Cryptographic Authentication Password authentication is subject to eavesdropping Alternative: Cryptographic challenge-response
More informationNetwork Security CHAPTER 31. Solutions to Review Questions and Exercises. Review Questions
CHAPTER 3 Network Security Solutions to Review Questions and Exercises Review Questions. A nonce is a large random number that is used only once to help distinguish a fresh authentication request from
More informationCS Computer and Network Security: Applied Cryptography
CS 5410 - Computer and Network Security: Applied Cryptography Professor Kevin Butler Fall 2015 Reminders Project Ideas are due on Friday. You should have a good handle on prospective ideas by now. Assignment
More informationCSE BAN Logic Presentation
(Mike Burrows Marin Abadi Roger Needham Published 1989 SRC Research Report 9 Presentation by Heather Goldsby Michelle Pirtle "! #! $ % Problem Solution BAN Logic Goals of BAN Terms Symbols Notation and
More informationSecurity+ Guide to Network Security Fundamentals, Third Edition. Chapter 11 Basic Cryptography
Security+ Guide to Network Security Fundamentals, Third Edition Chapter 11 Basic Cryptography Objectives Define cryptography Describe hashing List the basic symmetric cryptographic algorithms 2 Objectives
More informationNetwork Security and Internet Protocols
Network Security and Internet Protocols Luca Viganò Dipartimento di Informatica Università di Verona Sicurezza delle Reti A.A. 12/13 Lecture 5 Luca Viganò (Università di Verona) Network Security and Internet
More informationLecture 4: Authentication Protocols
Graduate Course on Computer Security Lecture 4: Authentication Protocols Iliano Cervesato iliano@itd.nrl.navy.mil ITT Industries, Inc @ NRL Washington DC http://www.cs.stanford.edu/~iliano/ DIMI, Universita
More informationCSC 474/574 Information Systems Security
CSC 474/574 Information Systems Security Topic 3.3: Security Handshake Pitfalls CSC 474/574 Dr. Peng Ning 1 Authentication Handshakes Secure communication almost always includes an initial authentication
More informationT Cryptography and Data Security
T-79.4501 Cryptography and Data Security Lecture 10: 10.1 Random number generation 10.2 Key management - Distribution of symmetric keys - Management of public keys Stallings: Ch 7.4; 7.3; 10.1 1 The Use
More informationCASP CompTIA Advanced Security Practitioner Study Guide: (Exam CAS-001)
CASP CompTIA Advanced Security Practitioner Study Guide: (Exam CAS-001) Gregg, Michael ISBN-13: 9781118083192 Table of Contents Foreword xxi Introduction xxvii Assessment Test xliv Chapter 1 Cryptographic
More informationBAN Logic. Logic of Authentication 1. BAN Logic. Source. The language of BAN. The language of BAN. Protocol 1 (Needham-Schroeder Shared-Key) [NS78]
Logic of Authentication 1. BAN Logic Ravi Sandhu BAN Logic BAN is a logic of belief. In an analysis, the protocol is first idealized into messages containing assertions, then assumptions are stated, and
More informationISACA CISA. ISACA CISA ( Certified Information Systems Auditor ) Download Full Version :
ISACA CISA ISACA CISA ( Certified Information Systems Auditor ) Download Full Version : http://killexams.com/pass4sure/exam-detail/cisa QUESTION: 390 Applying a digital signature to data traveling in a
More informationVerification of security protocols introduction
Verification of security protocols introduction Stéphanie Delaune CNRS & IRISA, Rennes, France Tuesday, November 14th, 2017 Cryptographic protocols everywhere! they aim at securing communications over
More informationUNIT - IV Cryptographic Hash Function 31.1
UNIT - IV Cryptographic Hash Function 31.1 31-11 SECURITY SERVICES Network security can provide five services. Four of these services are related to the message exchanged using the network. The fifth service
More informationInformation Security CS 526
Information Security CS 526 Topic 14: Key Distribution & Agreement, Secure Communication Topic 14: Secure Communication 1 Readings for This Lecture On Wikipedia Needham-Schroeder protocol (only the symmetric
More information0/41. Alice Who? Authentication Protocols. Andreas Zeller/Stephan Neuhaus. Lehrstuhl Softwaretechnik Universität des Saarlandes, Saarbrücken
0/41 Alice Who? Authentication Protocols Andreas Zeller/Stephan Neuhaus Lehrstuhl Softwaretechnik Universität des Saarlandes, Saarbrücken The Menu 1/41 Simple Authentication Protocols The Menu 1/41 Simple
More informationAPNIC elearning: Cryptography Basics
APNIC elearning: Cryptography Basics 27 MAY 2015 03:00 PM AEST Brisbane (UTC+10) Issue Date: Revision: Introduction Presenter Sheryl Hermoso Training Officer sheryl@apnic.net Specialties: Network Security
More informationCS 425 / ECE 428 Distributed Systems Fall 2017
CS 425 / ECE 428 Distributed Systems Fall 2017 Indranil Gupta (Indy) Dec 5, 2017 Lecture 27: Security All slides IG Security Threats Leakage Unauthorized access to service or data E.g., Someone knows your
More informationSecurity Handshake Pitfalls
Cryptographic Authentication Security Handshake Pitfalls Ahmet Burak Can Hacettepe University abc@hacettepe.edu.tr Password authentication is subject to eavesdropping Alternative: Cryptographic challenge-response
More informationWhat did we talk about last time? Public key cryptography A little number theory
Week 4 - Friday What did we talk about last time? Public key cryptography A little number theory If p is prime and a is a positive integer not divisible by p, then: a p 1 1 (mod p) Assume a is positive
More informationUnit III. Chapter 1: Message Authentication and Hash Functions. Overview:
Unit III Chapter 1: Message Authentication and Hash Functions Overview: Message authentication is a mechanism or service used to verify the integrity of a message. Message authentication assures that data
More informationCOMP 4704 Systems Security. Ramki Thurimella
COMP 4704 Systems Security Ramki Thurimella INFOSEC/OPSEC (pp. 20) OPSEC: Process to determine if friendly actions Can be observed by adversaries If it is useful to them If so, execute selected measures
More informationCryptography MIS
Cryptography MIS-5903 http://community.mis.temple.edu/mis5903sec011s17/ Cryptography History Substitution Monoalphabetic Polyalphabetic (uses multiple alphabets) uses Vigenere Table Scytale cipher (message
More informationLecture 30. Cryptography. Symmetric Key Cryptography. Key Exchange. Advanced Encryption Standard (AES) DES. Security April 11, 2005
Lecture 30 Security April 11, 2005 Cryptography K A ciphertext Figure 7.3 goes here K B symmetric-key crypto: sender, receiver keys identical public-key crypto: encrypt key public, decrypt key secret Symmetric
More informationComputer Security. 08r. Pre-exam 2 Last-minute Review Cryptography. Paul Krzyzanowski. Rutgers University. Spring 2018
Computer Security 08r. Pre-exam 2 Last-minute Review Cryptography Paul Krzyzanowski Rutgers University Spring 2018 March 26, 2018 CS 419 2018 Paul Krzyzanowski 1 Cryptographic Systems March 26, 2018 CS
More informationPublic-Key Cryptography. Professor Yanmin Gong Week 3: Sep. 7
Public-Key Cryptography Professor Yanmin Gong Week 3: Sep. 7 Outline Key exchange and Diffie-Hellman protocol Mathematical backgrounds for modular arithmetic RSA Digital Signatures Key management Problem:
More informationSSL Visibility and Troubleshooting
Page 1 of 6 view online Avi Vantage provides a number of features to help understand the utilization of SSL traffic and troubleshoot SSL-related issues. Visibility Every virtual service provides a number
More informationChapter 15: Security. Operating System Concepts 8 th Edition,
Chapter 15: Security, Silberschatz, Galvin and Gagne 2009 Chapter 15: Security The Security Problem Program Threats System and Network Threats Cryptography as a Security Tool User Authentication Implementing
More informationSecurity Handshake Pitfalls
Security Handshake Pitfalls 1 Authentication Handshakes Secure communication almost always includes an initial authentication handshake: Authenticate each other Establish sessions keys This process may
More informationSecuring Internet Communication: TLS
Securing Internet Communication: TLS CS 161: Computer Security Prof. David Wagner March 11, 2016 Today s Lecture Applying crypto technology in practice Two simple abstractions cover 80% of the use cases
More informationCSC 482/582: Computer Security. Security Protocols
Security Protocols Topics 1. Basic Concepts of Cryptography 2. Security Protocols 3. Authentication Protocols 4. Key Exchange Protocols 5. Kerberos 6. Public Key Infrastructure Encryption and Decryption
More informationSecurity Protocol Deployment Risk
Security Protocol Deployment Risk Simon N. Foley 1, Giampaolo Bella 2,3, and Stefano Bistarelli 4,5 1 Department of Computer Science, University College Cork, Ireland 2 SAP Research, Mougins, France 3
More informationOutline. Login w/ Shared Secret: Variant 1. Login With Shared Secret: Variant 2. Login Only Authentication (One Way) Mutual Authentication
Outline Security Handshake Pitfalls (Chapter 11 & 12.2) Login Only Authentication (One Way) Login i w/ Shared Secret One-way Public Key Lamport s Hash Mutual Authentication Shared Secret Public Keys Timestamps
More informationCryptographic Checksums
Cryptographic Checksums Mathematical function to generate a set of k bits from a set of n bits (where k n). k is smaller then n except in unusual circumstances Example: ASCII parity bit ASCII has 7 bits;
More informationThe Security Problem
CSC 4103 - Operating Systems Spring 2007 Lecture - XX Protection and Security Tevfik Koşar Louisiana State University April 12 th, 2007 1 The Security Problem Security must consider external environment
More informationMessage authentication. Why message authentication. Authentication primitives. and secure hashing. To prevent against:
Message authentication and secure hashing Why message authentication To prevent against: Masquerade/impersonation Modification of message content Modification of message sequence Acceptance of replayed/delayed
More informationMost Common Security Threats (cont.)
Most Common Security Threats (cont.) Denial of service (DoS) attack Distributed denial of service (DDoS) attack Insider attacks. Any examples? Poorly designed software What is a zero-day vulnerability?
More informationUnderstanding Cisco Cybersecurity Fundamentals
210-250 Understanding Cisco Cybersecurity Fundamentals NWExam.com SUCCESS GUIDE TO CISCO CERTIFICATION Exam Summary Syllabus Questions Table of Contents Introduction to 210-250 Exam on Understanding Cisco
More informationCSCE 715: Network Systems Security
CSCE 715: Network Systems Security Chin-Tser Huang huangct@cse.sc.edu University of South Carolina Web Security Web is now widely used by business, government, and individuals But Internet and Web are
More informationContents Digital Signatures Digital Signature Properties Direct Digital Signatures
Contents Digital Signatures... 197 Digital Signature Properties... 198 Direct Digital Signatures... 198 199...قابلداوری Arbitrated Digital Signatures Arbitrated Digital Signature Technaiques... 200 Authentication
More informationWHAT FUTURE FOR CONTACTLESS CARD SECURITY?
WHAT FUTURE FOR CONTACTLESS CARD SECURITY? Alain Vazquez (alain.vazquez@louveciennes.sema.slb.com) 1/27 AV Contents Major contactless features : summary Contactless major constraints Major security issues
More informationChapter 9: Database Security: An Introduction. Nguyen Thi Ai Thao
Chapter 9: Database Security: An Introduction Nguyen Thi Ai Thao thaonguyen@cse.hcmut.edu.vn Spring- 2016 Outline Introduction to Database Security Issues Types of Security Threats to databases Database
More informationAN IPSWITCH WHITEPAPER. The Definitive Guide to Secure FTP
AN IPSWITCH WHITEPAPER The Definitive Guide to Secure FTP The Importance of File Transfer Are you concerned with the security of file transfer processes in your company? According to a survey of IT pros
More informationCryptography and Network Security Chapter 13. Digital Signatures & Authentication Protocols
Cryptography and Network Security Chapter 13 Digital Signatures & Authentication Protocols Digital Signatures have looked at message authentication but does not address issues of lack of trust digital
More information