EEC484584 Computer Networks

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EEC-484/584Computer Networks

• Lecture 1
• Wenbing Zhao
• Cleveland State University
• wenbing_at_ieee.org

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Instructor Information

• Instructor Dr. Wenbing Zhao
• Office SH434
• Email wenbing_at_ieee.org
• Lecture MW 600-750pm, SH306
• Office hours MW 200-400pm and by appointment

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What is Computer Network?

• A group of computers inter-connected together

Local Area Network
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What is Computer Network?

• A group of computer inter-connected together

Wide Area Network
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What are the Elementsin a Computer Network?

• Hosts computers
• Communication medium cables, wireless medium
  (EM waves)
• Routers forward a packet from one place to
  another, decide on a path from source to
  destination
• Protocols rules governing the communication

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Achieving Connectivity is Not Easy
Transport Service User

• Layered approach
• We will study issues in each layer in a top-down
  order
• Application
• Transport
• Network
• Link

Transport Service Provider
Physical Layer is not covered
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Course Objectives

• Good understanding of the computer networking
  technologies
• How connectivity is achieved?
• Hands on experience
• Labs observe how protocols work
• Project write about computer networks elements
  and hopefully write some demo programs

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Prerequisite

• Officially graduate standing
• Ideally You should have sufficient computer
  engineering background
• You have taken undergraduate-level operating
  systems, data structure and algorithms, and
  programming language courses
• You know how to write technical reports in
  English (in your own words)

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Topics

• Overview of computer networks
• Types of computer networks
• Reference models
• Protocols, services and interfaces
• Circuit switched vs. packet switched
• Connection oriented vs. connectionless

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Topics

• Application Layer
• HyperText Transfer Protocol (HTTP)
• Domain Name Service (DNS)
• FTP, Email
• Physical Layer skipped

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Topics

• Transport layer
• Main service End-to-end reliable communication
• User Datagram Protocol (UDP)
• Transport Control Protocol (TCP)

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Topics

• Network layer
• Main service routing over multiple hops
• Routing algorithms
• Internet Protocol (IP)
• IP address allocation
• Internet Control Protocols ICMP, ARP, DHCP

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Topics

• Data Link Layer (part 1) Basic communication
  protocols
• Main service provide point-to-point single hop
  communication service to higher layer
• Framing group bits together
• Error control
• Flow control

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Topics

• Data Link Layer (part 2) Medium access control
  protocols
• Shared medium, multiple concurrent users, need to
  address conflict

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Labs

• Purpose Observe how protocols work
• Tools used Wireshark
• 5 lab sessions
• HTTP
• DNS
• TCP
• IP
• Ethernet, ARP DHCP

Tell me and I forget. Show me and I remember.
Involve me and I understand. - Chinese proverb
Lab instructions taken from Kuroses book
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Labs

• Lab sessions are mandatory unless an exception is
  granted in advance
• I will not accept the lab report if you do now
  show up during the lab session without prior
  notice
• Lab report must be typed (with both questions and
  answers) and submitted in hardcopy on or before
  due date

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Special Labs

• Learning networking protocols with iPod Touch
  Sponsored by the CSU Center for Teaching
  Excellence
• Up to three labs
• Reliable data communication
• Routing
• Medium access protocols

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Projects

• Build a wiki page
• For individual or a team of two
• To gain extra-credit, you are encouraged to build
  demonstration programs
• Java applet or plain Java application,
• NS2 simulator

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Project

• Select a topic related to Computer Networks and
  build a wiki page for the topic on
  http//www.pbwiki.com/ or a similar Web hosting
  site
• For example topics, see the syllabus
• Furthermore, peer-review and revision steps are
  required
• Each team is required to review three wiki pages
  built by other teams anonymously
• You must revise your page according to the reviews

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Class Participation

• 10 of the course credit
• In general, there is a mock quiz in the beginning
  of each lecture, so that
• I know who is here I get feedback for my
  teaching
• To obtain the full credit for class
  participation, you must satisfy ALL of the
  following conditions
• You do not miss more than 2 lectures
• You do not miss any quiz and lab sessions
• You asked at least 10 questions during the
  semester
• You will lose all 10 credit if you miss more
  than 6 lectures/labs (unless an exception is
  granted)

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Class Participation

• Send me an email with the following information
  for each question you have asked within 24 hours
  after each lecture
• The question you asked
• My response
• Your comment on my response and suggestion for
  improvement, if any

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Class Participation

• You are also encouraged to send me
  comments/suggestions on how you would like me to
  improve my teaching so that it is more conducive
• For each piece of comment/suggestion, it will be
  counted as 2 questions
• If you max out the class participation credit,
  you will get extra credit if you provide further
  feedbacks

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Quizzes

• 5 quizzes. Basically one quiz for each layer
• The quizzes are closed book and closed notes,
  except that you are allowed to bring with you a
  one-page hand-written cheat sheet no larger than
  the US letter size (double-sided allowed)
• No makeup quizzes!
• No midterms and final exam
• Perks only the best of 4 quizzes will be counted
  towards your grade

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Grading

• Grading scale
• A 90-100
• A- 85-89
• B 75-84
• B 65-74
• B- 60-64
• C 50-59
• F

• Class participation 10
• Quizzes 50
• Labs 20
• Project 20

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Do not cheat!

• Do not copy other students lab report, quizzes
  or projects
• Do not copy someone elses work found on the
  Internet
• You can quote a sentence or two, but put those in
  quote and give reference

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Consequences for Cheating

• You get 0 credit for the task you have cheated
• If the task is worth more than 25 of the course,
  it is considered a major infraction
• Otherwise, it is considered a minor infraction
• For major infraction and repeated minor
  infractions
• You will get an F grade, and
• You may be suspended or repulsed from CSU
• CSU Code of Conduct
• http//www.csuohio.edu/studentlife/StudentCodeOfCo
  nduct.pdf

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Reference Texts

• Andrew S. Tanenbaum
• Computer Networks
• 4th Edition (or later), Prentice-Hall, 2003
• James F. Kurose, Keith W. Ross,
• Computer Networking A Top-Down Approach
  Featuring the Internet
• 3rd Edition (or later), Addison-Wesley, 2004

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Additional Information

• Anonymous email
• teachingcsu_at_gmail.com
• Password
• if you are not happy, please do let me know
• Course Web site
• http//academic.csuohio.edu/zhao_w/teaching/EEC584
  -S09/eec584.htm
• Lecture notes will be posted