Today: about the class

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Today about the class

• Course info
• A brief story

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CS438/538Computer Communication Networks
Computer Networking A Top Down Approach, 4rd
edition. Jim Kurose, Keith RossAddison-Wesley,
July 2007.
Student Resources http//wps.aw.com/aw_kurose_n
etwork_4/63/16303/4173750.cw/index.html
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CS438/538Computer Communication Networks

• Instructor Xiaoyan Hong
• Email hxy_at_cs.ua.edu
• Office Houser 116A
• Lectures Tue/Thu 1230pm -145pm, EE 110
• Office hours 200-300pm Tue and Wed, or by
  appointment
• Course homepage
• http//cs.ua.edu/438

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What this course is about

• What are the underlying concepts and technologies
  that make the Internet run?
• First/introductory course in computer networking
• Understand the basics of computer networks
  design and practice
• Learn the basics of TCP/IP protocol suite in the
  current Internet
• Key protocols
• Introduce to network programming

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• Computer communication history and the growing
  demand
• Human communications to computer communications
• face to face, telephone

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Internet History
1961-1972 Early packet-switching principles

• 1961 Kleinrock - queueing theory shows
  effectiveness of packet-switching
• 1964 Baran - packet-switching in military nets
• 1967 ARPAnet conceived by Advanced Research
  Projects Agency
• 1969 first ARPAnet node operational

• 1972
• ARPAnet public demonstration
• NCP (Network Control Protocol) first host-host
  protocol
• first e-mail program
• ARPAnet has 15 nodes

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Internet History
1972-1980 Internetworking, new and proprietary
nets

• 1970 ALOHAnet satellite network in Hawaii
• 1974 Cerf and Kahn - architecture for
  interconnecting networks
• 1976 Ethernet at Xerox PARC
• ate70s proprietary architectures DECnet, SNA,
  XNA
• late 70s switching fixed length packets (ATM
  precursor)
• 1979 ARPAnet has 200 nodes

• Cerf and Kahns internetworking principles
• minimalism, autonomy - no internal changes
  required to interconnect networks
• best effort service model
• stateless routers
• decentralized control
• define todays Internet architecture

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Internet History
1980-1990 new protocols, a proliferation of
networks

• 1983 deployment of TCP/IP
• 1982 smtp e-mail protocol defined
• 1983 DNS defined for name-to-IP-address
  translation
• 1985 ftp protocol defined
• 1988 TCP congestion control

• new national networks Csnet, BITnet, NSFnet,
  Minitel
• 100,000 hosts connected to confederation of
  networks

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Internet History
1990, 2000s commercialization, the Web, new apps

• Early 1990s ARPAnet decommissioned
• 1991 NSF lifts restrictions on commercial use of
  NSFnet (decommissioned, 1995)
• early 1990s Web
• hypertext Bush 1945, Nelson 1960s
• HTML, HTTP Berners-Lee
• 1994 Mosaic, later Netscape
• late 1990s commercialization of the Web

• Late 1990s 2000s
• more killer apps instant messaging, P2P file
  sharing
• network security to forefront
• est. 50 million host, 100 million users
• backbone links running at Gbps

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Internet History

• 2007
• 500 million hosts
• Voice, Video over IP
• Computer networks support human communications
• P2P applications BitTorrent (file sharing) Skype
  (VoIP), PPLive (video)
• more applications YouTube, gaming
• wireless, mobility

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• About the textbook
• Resources
• Internet Engineering Task Force (IETF)
  http//www.ietf.org
• an open international community
• concerned with the development and operation of
  the Internet and its architecture. -- develop
  open source standards, RFCs.
• The IETF meets three times a year much of its
  ongoing work is conducted via mailing lists by
  working groups.
• The IETF was formally established by the Internet
  Architecture Board (IAB), http//www.isi.edu/iab,
  in 1986. IETF is administered by the Internet
  Society, http//www.isoc.org, whose Web site
  contains lots of high-quality, Internet-related
  material.

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Practical issues

• Not on developing Internet based applications,
  but could be helpful
• Understand your daily network related activities
  better (Phishing example)
• Job relating to networks
• Research (project) experience to enhance your
  skills

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course outline

• Introduction Internet overview, packet
  switching, layering structure, performance
• Application layer Principles, HTTP, FTP, Email,
  DNS, P2P, Socket programming
• Transport layer Principles, UDP, TCP
• Network layer IP, routers, routing protocols
• Link layer and local area networks Error
  detection and correction, MAC ARP, Ethernet,
  802.11, mobility
• Wireless and mobility
• Network Security

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Course Workload

• Reading for every lecture
• Assignments
• At least a week between posting and due
• homework solutions posted in the evening of the
  due day.
• work individually
• paper-based homework
• programming assignments (small projects)
• Midterm and final exams
• Closed book/notes/everything
• Last but not least Classroom participation
• CS 538
• You will have additional wireshark labs as
  assignments (work in teams).
• Related exam problems.

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Grading breakdown

• Assignments (paper-based and programming) 30
• Midterm 25
• Final exam 40
• Class participation 5
• The midterm and final are closed book and closed
  notes.

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Course Policies

• ONE WEEK for questions regarding the grading,
  after the date of returning.
• no late assignment turn-ins are accepted for
  credit
• no make-up exams
• Unless reasonable excuses (with documents)
• no misconduct
• copy others work

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Lecture Teaching

• "Taking notes in class helps me understand
  better"
• posted lecture notes only bullets.

• your notes go around

• Client communicates with the server through the
  net

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Suggested reading

• Internet History Chapter 1.8