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AGENDA• Overview of Security & Needs• Concepts, Types of Viruses• Different Types of Security• Threats in Network• Hacking, Ethical Hacking• Attacks, services and mechanisms• Security attacks-Types• Security services• Methods of Defense• A model for Internetwork Security
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Overview
• What is security?• Why do we need security?• Who is vulnerable?
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What is “Security”
Security is state of having1. Freedom from risk or danger; safety.2. Freedom from doubt, anxiety, or fearDefinition:
Security is the protection of assets. Three main aspects of security are1. Protection2. Detection3. Reaction.
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Why do we need security?
• Protect vital information while still allowing access to those who need it– Trade secrets, medical records, etc.
• Provide authentication and access control for resources– Ex: Bank Identity Card, ATM Card
• Guarantee availability of resources– Must be available all the time
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Need for Security
• The Information Age- Internet Highway• Digital Assets- emails, documents• Static Assets- pictures, databases• Assets on Transit- emails(Comm. Networks)
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Who is vulnerable?
• Financial institutions and banks• Internet service providers• Pharmaceutical companies• Government and defense agencies• Internet users• Multinational corporations• ANYONE ON THE NETWORK
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Different Types of Security-Definitions
• Computer Security - generic name for the collection of tools designed to protect hardware or software modules.
• Network Security - measures to protect data during their transmission
• Internet Security - measures to protect data during their transmission over a collection of interconnected network
• Information Security- All the three areas
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Basic Terminologies
• Cryptography– Study of mathematical techniques related to aspects of
information security (Set of techniques)• Cryptanalysis
– The process of breaking the security policies• Cryptology - Cryptography + cryptanalysis• Cryptosystems are computer systems used to encrypt data
for secure transmission and storage
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Types of Computer Virus
1.Time Bomb
2.Logical Bomb
3.Worm
4.Boot Sector Virus
5.Macros Virus
6.Trojan Horse
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Types of Viruses
• Time Bomb – Active when time/date comes• Logical Bomb – Active when some action comes• Worm- Self replicating in networks • Boot Sector Virus- During system boot, boot sector virus is
loaded into main memory and destroys data stored in hard disk
• Micro Virus- It is associated with application software like word and excel
• Trojan Horse- usually email virus
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Launching the attackSteps are
1. Vulnerability
2. Threat
3. Discovery of Vulnerability
4. Exploitation of Vulnerability
5. Attack
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Attacks, Services and Mechanisms
• Security Attack: Any action that compromises the security of information.
• Security Mechanism: A mechanism that is designed to detect, prevent, or recover from a security attack.
• Security Service: A service that enhances the security of data processing systems and information transfers. A security service makes use of one or more security mechanisms.
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Different Types of Security Attacks
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Security Attacks
• Interruption: This is an attack on availability
• Interception: This is an attack on confidentiality
• Modification: This is an attack on integrity• Fabrication: This is an attack on
authenticity
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Security Goals
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Threats in Networks
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In This Section
• What makes a network Vulnerable– Reasons for network attacks
• Who Attacks Networks?– Who are the attackers? Why people attack?
• Threats in Network transmission: Eavesdropping and Wiretapping– Different ways attackers attack a victim
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What Makes a Network Vulnerable • How network differ from a stand-alone
environment:– Anonymity
• Attacker can mount an attack from thousands of miles away; passes through many hosts
– Many points of attack• Both targets and origins • An attack can come from any host to any host
– Sharing • More users have the potential to access networked
systems than on single computers
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• How network differ from a stand-alone environment:– Complexity of System
• Reliable security is difficult to obtain• Complex as many users do not know what their computers are
doing at any moment
– Unknown Perimeter • One host may be a node on two different networks• Causing uncontrolled groups of possibly malicious users
– Unknown Path • Can have multiple paths from one host to another.
What Makes a Network Vulnerable
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Who Attacks Networks1. Challenge – what would happen if I tried this approach
or technique? Can I defeat this network?
2. Fame
3. Money and Espionage(Spy)
4. Organized CrimeIdeology
Hacktivism – breaking into a computer system with the intent of disrupting normal operations but not causing serious damage
Cyberterroism- more dangerous than hacktivism can cause grave harm such as loss of life or severe economic damage
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Reference
• Asoke K Talukder, Manish Chaitanya, Architecting Secure Software System, Aeurbach Publication, 2008
• Howard M, Lipner S, The Security Development Lifecycle, Microsoft Press, 2006
• Frank Swiderski, Window Snyder, Threat Modeling, Microsoft Press, 2004
• John Viega, Gary McGraw, Building secure Software, How to Avoid Security problems in the Right Way, Addison-Wesley 2001
• Tom Gallagher, Bryan Jeffries, Lawrence Landauer, Hunting Security Bugs, Microsoft Press, 2006
• Ross Anderson, Security Engineering: A guide to Building dependable Distributed systems, John wiley, 2001.