CS 4803 Computer and Network Security

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CS 4803 Computer and Network Security

• Dr. Wenke Lee
• wenke_at_cc.gatech.edu

The lecture notes have incorporated course
materials developed by Dr. S. Felix Wu of UC
Davis, Dr. Fengmin Gong of IntruVert, Dr. Matt
Bishop of UC Davis, and Dr. Henning Schulzrinne
of Columbia University.
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Course Objectives

• Understanding of basic issues, concepts,
  principles, and mechanisms in information
  security.
• Security goals and threats to computer and
  networking infrastructure and applications.
• Introduction to cryptography.
• System security applications.
• Network security applications.
• Exposure to commercial as well as research
  security technologies.

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Course Styles

• Descriptive what is out there.
• Critical what is wrong with ...
• Skill oriented homework with programming and lab
  projects.
• Explore!
• Interactive discussion and questions encouraged
  and considered in grade
• Students are encouraged to present their findings
• Information sharing home page and message
  board/email list.

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Course Outline

• Fundamentals
• Overview of computer security
• Fundamental results
• Security policy and models
• Design principles and implementation issues
• Vulnerability analysis and auditing
• Program security, operating system security, and
  database security
• Cryptography
• Secret key cryptography
• Hashes and message digests
• Public key cryptography
• Information hiding

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Course Outline - Contd

• Network and system security applications
• Authentication and security handshakes pitfalls
• IP security
• Web and E-commerce
• Virus/worm detection, firewalls, intrusion
  detection.
• Hacking and forensics
• Writing secure code

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Prerequisites

• Operating systems, networking, discrete
  mathematics, and programming (C or C, Java).

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Textbooks and References

• Required textbooks
• Computer Security Art and Science by Matt Bishop
• Network security PRIVATE communication in a
  PUBLIC world by Kaufman, Perlman, and Speciner.
• Reference text(s) and papers
• Security in Computing by Charles Pfleeger and
  Shari Pfleeger.
• Additional materials see course Web page.

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Course Mechanics

• WWW page
• For course materials, e.g., lecture slides,
  homework files, papers, tools, etc.
• Grading 60 homework, 15 midterm, and 25 final
  (or course project)
• Course participation 5 extra credits.

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Motivations
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Why Is Security Important

• Computers and networks are the nerves of the
  basic services and critical infrastructures in
  our society
• Financial services and commerce
• Transportation
• Power grids
• Etc.
• Computers and networks are targets of attacks by
  our adversaries

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A Motivating Example

• Requirements of an e-Commerce site
• Performance
• of current transactions
• Usability
• Easy to follow GUIs, convenience (cookies?)
• Security
• Secure transmission and storage of costumer
  financial/personal data
• Protect the Web servers and the enterprise
  network from illegitimate access
• Provide continuous/uninterrupted services

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Why Is Security Hard (and Harder)

• The complexity of computers and networks
• User expectation
• User ignorance
• Social engineering
• Defense is inherently more expensive
• Offense only needs the weakest link

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Trends by Application Demands

• Hunger for bandwidth
• Hardware (Physics) breakthroughs seem to come
  easier than software
• Wider spectrum of application sophistication
• Best-effort to guaranteed
• Built-in security?
• Drive for ubiquitous access
• Economics/profitability

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Quest for Better Services

• Real-time audio/video requires guaranteed
  end-to-end delay and jitter bounds.
• Adaptive multimedia application requires minimum
  bandwidth and loss assurance.
• Intelligent application demands reliable feedback
  from the network.
• Security.

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Quest for Ubiquitous Access ...

• Information age is a reality.
• Everything depends on reliable and efficient
  information processing.
• Quality of our everyday life.
• Development of national/world economy.
• Security of national defense/world peace.
• Networking is one critical part of this
  underlying information infrastructure!

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Economic Pressure

• Service providers want the most bang on their
  buck - the most profitable technology?
• Cautious adoption of new technologies
• Even for security
• Emphasis on leveraging deployed technologies
• Increased utilization of existing facilities

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Networking Technologies

• Switching modes.
• Circuit switching.
• Packet switching - Ethernet, HIPPI, fiber
  channel, IP routing, frame relay, ATM, IP
  switching/tag switching.
• High-speed transmission media.
• SONET/SDH, WDM.
• Ubiquitous access media.
• xDSL/cable modem, IEEE802.11, LEOSs.
• We will study the common security issues.

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The Internet
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Layered Store-and-forward
User A
User B
Application
Transport
Network
Link
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Security Implications

• Vulnerabilities - from weak design, to
  feature-rich implementation, to compromised
  entity
• Heterogeneous networking technologies adds to
  security complexity
• But improves survivability
• Higher-speed communication puts more information
  at risk in given time period
• Easier to attack than to defend
• Ubiquitous access increases exposure to risks

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The Good News ...

• Plenty of basic means for end-user protection -
  authentication, access control, integrity
  checking
• Intensive RD effort on security solutions
  (government sponsored research private industry
  development)
• Increasing public awareness of security issues
• New crops of security(-aware) researchers and
  engineers
• YOU!

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The Bad News ...

• (Existing) information infrastructure as a whole
  is very vulnerable, which makes all critical
  national infrastructure vulnerable
• e.g., Denial-of-service attacks are particularly
  dangerous to the Internet infrastructure
• Do we continue to band-aid or re-design?
• Serious lack of effective technologies, policies,
  and management framework