CSE 422 Computer Networks Dr. Abdol-Hossein Esfahanian Sunday, April 16, 2017 CSE 422 Computer Networks Dr. Abdol-Hossein Esfahanian Computer Science and Engineering Department 3115 Engineering Building © 2006 by A-H. Esfahanian. All Rights Reserved.

Catalog Description CSE 422: Computer Networks Sunday, April 16, 2017 Catalog Description CSE 422:  Computer Networks Prerequisite: (STT 351 or ECE 280) and (CSE 320 or ECE 331) and (CSE 410 or concurrently) Description: Computer network architectures and models. Physical media and signaling. Data link protocols. Medium access control. Routing and IP. Transport services including TCP/UDP. Network applications. Local-area and wide-area networks. © 2006 by A-H. Esfahanian. All Rights Reserved.

Course Objectives Learn the fundamentals of computer networking. Sunday, April 16, 2017 Course Objectives Learn the fundamentals of computer networking. Understand how these fundamentals are applied in real networks, in particular, the Internet. Understand the relationship between theory and practical design issues in network hardware and software. Gain an in-depth understanding of how network applications software is supported by underlying protocols. Learn that computer networks evolve. © 2006 by A-H. Esfahanian. All Rights Reserved.

Course Outline Introduction Physical Layer Sunday, April 16, 2017 Course Outline Introduction Overview of computer networks Network architecture models Network programming interfaces Physical Layer Services provided to the data link layer Theoretical basis for data communication Bandwidth limitations Analog and digital transmission Transmission media Signaling methods Multiplexing and switching Wireless/Mobile communication © 2006 by A-H. Esfahanian. All Rights Reserved.

Course Outline … Data Link Layer Medium Access Sublayer Network Layer Sunday, April 16, 2017 Course Outline … Data Link Layer Services provided to the network layer Error detection and correction Stop-and-wait protocols Sliding window protocols Medium Access Sublayer Channel allocation problems Contention-based protocols Ethernet architecture 802.x protocols Network Layer Services provided to the Transport layer Routing algorithms Internetworking Internet Protocol © 2006 by A-H. Esfahanian. All Rights Reserved.

Course Outline… Transport Layer Application-level Protocol Standards Sunday, April 16, 2017 Course Outline… Transport Layer Services provided to the upper layers Connection management UDP, TCP, sockets Performance issues Application-level Protocol Standards Domain name services Application standards: SNMP, FTP, TELNET, SMTP, NNTP, HTTP Network Security Introduction to Cryptography Public-key algorithms © 2006 by A-H. Esfahanian. All Rights Reserved.

Class Procedures and Policies Sunday, April 16, 2017 Class Procedures and Policies Class attendance and participation (5%) Homework & Labs (15%) Two exams (25% each) and a final (30%) Course Grade is based on straight scale; percentages are on total scores possible: 93 – 100% 4.0 85 – 92 % 3.5 80 – 84 % 3.0 75 – 79 % 2.5 70 – 74 % 2.0 65 – 69 % 1.5 60 – 64 % 1.0 © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Class Procedures …….. Class notes and other course materials and resources will be available on the course website: http://www.cse.msu.edu/~cse422/ It is password protected (cse422, tan4me). Visit this site on regular basis. It is your responsibility! © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Class Procedures When attending the class, we ask you to observe a few simple rules which are meant to create a better learning environment. Come to class on time since we will start lectures right away. Once class begins, we expect students to pay attention and not read the newspaper or talk, etc. TURN YOUR CELL PHONE OFF. If you have a question, do not hesitate to ask. Others are likely to have the same question. Do not be afraid to ask questions and slow down the pace of the class. If we feel there are too many questions and that we must move on, we will say so, but that should not be taken to mean that the question was ``dumb'' or inappropriate. © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Class Procedures … Textbook: Computer Networks, by Andrew Tanenbaum, Fourth Edition. Students are required to get a copy of this textbook. You will have regular reading assignments from this textbook. © 2006 by A-H. Esfahanian. All Rights Reserved.

Class Procedures … Instructor: Dr. Abdol-Hossein Esfahanian Sunday, April 16, 2017 Class Procedures … Instructor: Dr. Abdol-Hossein Esfahanian Email: esfahanian@cse.msu.edu Url: http://www.cse.msu.edu/~esfahani/ Office: 2134EB Tel: 353-4389 Office Hours: Wed 1:00pm – 2:00pm, or by appointment, or whenever you can find me. © 2006 by A-H. Esfahanian. All Rights Reserved.

Class Procedures … Course TA: Bo Wang [wangbo@msu.edu] Sunday, April 16, 2017 Class Procedures … Course TA: Bo Wang [wangbo@msu.edu] Office hours will be on Thursdays 10-12 noon. © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Class Procedure … All students will have computer accounts on CSE machines. If your home account is under another domain, then it is your responsibility to have your mail forwarded. Students are encouraged to work together on homework assignments. However, each student must do his/her write-up. Unless otherwise specified, exams will be closed-book and will cover material assigned from the texts, notes, handouts, and lectures. For exams only, you are allowed to use an 8½ x 11 note sheet. You should utilize this to write down important formulae, proof techniques etc. Being caught cheating on ANY aspect of the course is grounds for receiving a grade of 0.0 for the course. © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Academic Integrity Academic Integrity is very important in this class and in this university. It is important that students do their work on their own without help from anyone except the instructor or the teaching assistant. Students are permitted to discuss the homework problems with each other. However, the work they turn in must be completely their own. Obviously, no cooperation is permitted during examinations. Students violating this will be dealt with according to the university policy. © 2006 by A-H. Esfahanian. All Rights Reserved.

Make note of these dates. Normally there will NOT be any Sunday, April 16, 2017 Important dates Exam #1 Thursday Feb 22, 2007 Exam #2 Thursday April 5, 2007 Final: Thursday May 3, 2007, 10:00-12:00 noon Make note of these dates. Normally there will NOT be any make-up exams. © 2006 by A-H. Esfahanian. All Rights Reserved.

Technologies over the centuries Sunday, April 16, 2017 Technologies over the centuries 18th Century: Mechanical Systems Accompanying The Industrial Revolution 19th Century: Age of The Steam Engine 20th Century: Information Gathering, Processing, and Distribution. Examples: Worldwide Telephone Network Invention of Radio and TV Computer Industry Launching of Communication Satellites © 2006 by A-H. Esfahanian. All Rights Reserved.

A brief history of Networking Sunday, April 16, 2017 A brief history of Networking 1961-1972: Early packet-switching principles 1972: ARPAnet demonstrated publicly NCP (Network Control Protocol) first host-host protocol First e-mail program ARPAnet has 15 nodes 1961: Kleinrock - queuing 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 © 2006 by A-H. Esfahanian. All Rights Reserved.

Networking History (Cont.) Sunday, April 16, 2017 Networking History (Cont.) 1972-1980: Internetworking, new and proprietary nets Cerf and Kahn’s internetworking principles: minimalism, autonomy - no internal changes required to interconnect networks best effort service model stateless routers decentralized control define today’s Internet architecture 1970: ALOHAnet satellite network in Hawaii 1973: Metcalfe’s PhD thesis proposes Ethernet 1974: Cerf and Kahn - architecture for interconnecting networks late70’s: Proprietary Architectures: DECnet, SNA, XNA late 70’s: switching fixed length packets (ATM precursor) 1979: ARPAnet has 200 nodes © 2006 by A-H. Esfahanian. All Rights Reserved.

Networking History (Cont.) Sunday, April 16, 2017 Networking History (Cont.) 1980-1990: new protocols, a proliferation of networks new national networks: Csnet, BITnet, NSFnet, Minitel 100,000 hosts connected to confederation of networks 1983: deployment of TCP/IP 1983: smtp e-mail protocol defined 1983: DNS defined for name-to-IP-address translation 1985: ftp protocol defined 1988: TCP congestion control © 2006 by A-H. Esfahanian. All Rights Reserved.

Networking History (Cont.) Sunday, April 16, 2017 Networking History (Cont.) 1990’s: commercialization, the WWW Early 1990’s: ARPAnet decommissioned 1991: NSF lifts restrictions on commercial use of NSFnet (decommissioned, 1995) early 1990s: WWW hypertext [Bush 1945, Nelson 1960’s] HTML, http: Berners-Lee 1994: Mosaic, later Netscape late 1990’s: commercialization of the WWW Late 1990’s: est. 50 million computers on Internet est. 100 million+ users backbone links running at 1 Gbps © 2006 by A-H. Esfahanian. All Rights Reserved.

The ARPANET Growth of the ARPANET (a) December 1969. (b) July 1970. Sunday, April 16, 2017 The ARPANET Growth of the ARPANET (a) December 1969. (b) July 1970. (c) March 1971. (d) April 1972. (e) September 1972. © 2006 by A-H. Esfahanian. All Rights Reserved.

Hosts on the Web Sunday, April 16, 2017 © 2006 by A-H. Esfahanian. All Rights Reserved.

Source: http://www.websiteoptimization.com/bw/0611/ Sunday, April 16, 2017 Over the past year, the UK added a net increase of 6.1 subscribers per 100 inhabitants. The US added 4.7 subscribers, while Japan added 2.6. The UK's superior growth rate propelled it past the US and Japan to become second only to Canada among G7 countries surveyed in broadband penetration. Source: http://www.websiteoptimization.com/bw/0611/ © 2006 by A-H. Esfahanian. All Rights Reserved.

Total Broadband Subscribers Sunday, April 16, 2017 Total Broadband Subscribers OECD; Organization for Economic Co-operation and Development The OECD groups 30 member countries sharing a commitment to democratic government and the market economy. With active relationships with some 70 other countries and economies, NGOs and civil society, it has a global reach. Best known for its publications and its statistics, its work covers economic and social issues from macroeconomics, to trade, education, development and science and innovation. http://www.oecd.org/about/0,2337,en_2649_201185_1_1_1_1_1,00.html Over the past year, the US has maintained its lead with 31% of total broadband subscribers worldwide. Source: http://www.websiteoptimization.com/bw/0611/ © 2006 by A-H. Esfahanian. All Rights Reserved.

Broadband Penetration by Country and Population Density - June 2006 Sunday, April 16, 2017 Broadband Penetration by Country and Population Density - June 2006 Source: http://www.websiteoptimization.com/bw/0611/ © 2006 by A-H. Esfahanian. All Rights Reserved.

Lecture 01 Tuesday January 09, 2007 Sunday, April 16, 2017 Lecture 01 Tuesday January 09, 2007 © 2006 by A-H. Esfahanian. All Rights Reserved.

Notable Read Chapter 1 Read the article Nothing but Net Sunday, April 16, 2017 Notable Read Chapter 1 Read the article Nothing but Net Forthcoming Topics What is a computer network Classification of networks The layering concept © 2006 by A-H. Esfahanian. All Rights Reserved.

What is a Computer Network? Sunday, April 16, 2017 What is a Computer Network? A computer network is an interconnected collection of autonomous computers. Two computer are interconnected if they are able to exchange information Two computer are autonomous if they are capable of operating independently, that is, neither is capable of forcibly starting, stopping, or controlling the other. © 2006 by A-H. Esfahanian. All Rights Reserved.

What is not a Computer Network? Sunday, April 16, 2017 What is not a Computer Network? Master/slave systems, in which one computer controls several others single-host networks, consisting of a single computer with an attached collection of terminals. Multicomputers, such as the old hypercube, which normally operate as a back-end to a host system. In terms of (operating) systems, there is some confusion between network systems and distributed systems © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Network Systems An interconnection of computers through a communication subnet The user is aware of the networking of different computers Network services remote login remote file transfer remote job execution mail service Etc, © 2006 by A-H. Esfahanian. All Rights Reserved.

Sunday, April 16, 2017 Distributed Systems A distributed system is a special case of computer network, in which the network of computers appears as a single system to the user, all operations being performed transparently. Combination of an interconnection of computers and distributed control programs. Most operations are transparent to the user. User sees an integrated service environment; distributed system is hidden from the user. © 2006 by A-H. Esfahanian. All Rights Reserved.

Distributed Systems … Provides location-independent services. Sunday, April 16, 2017 Distributed Systems … Provides location-independent services. The difference lies with the software rather than hardware. Allows concurrent processing and greater sharing of resources Permits development of distributed application programs Ongoing problems in distributed systems load balancing fault-tolerance © 2006 by A-H. Esfahanian. All Rights Reserved.

Applications of Networks Sunday, April 16, 2017 Applications of Networks Access to Remote Programs Simulation Computer Aided Ed., Medical Diagnosis Access to Remote Data Bases Reservations For Hotels, Airplanes Home Banking Automated Newspaper Automated Library Access to Information System: (e.g. World Wide Web) © 2006 by A-H. Esfahanian. All Rights Reserved.

Applications of Networks… Sunday, April 16, 2017 Applications of Networks… Communication Medium Electronic Funds Transfer System Electronic Mail Teleconferencing Worldwide Newsgroups International Contacts by Humans Entertainment Industry Video On Demand Multiperson real-time simulation games Selecting any movie/TV program ever made Live TV may become interactive with audience © 2006 by A-H. Esfahanian. All Rights Reserved.

Social Issues Views on politics, religion, …., become distributed Sunday, April 16, 2017 Social Issues Views on politics, religion, …., become distributed Newsgroups debate sensitive issues Network operators risk being sued for contents Rights to free speech may be violated Anonymous messages can be desirable, but ... © 2006 by A-H. Esfahanian. All Rights Reserved.

Network Classification based on physical size Sunday, April 16, 2017 Network Classification based on physical size Typical Distance Area covered System Type 10m – 1Km Room, Building Campus Local Area Networks 10 – 100Km City, County, Continent Metropolitan Area, Wide Area Network Over 100Km Planet Internet © 2006 by A-H. Esfahanian. All Rights Reserved.

Network Structure Communication Subnet (Subnet) Sunday, April 16, 2017 Network Structure Communication Subnet (Subnet) Switching Elements (Routers) Transmission Lines (Circuits) Boundary of the Communication subnet Routers Hosts © 2006 by A-H. Esfahanian. All Rights Reserved.

Types of Design For Subnets Sunday, April 16, 2017 Types of Design For Subnets Point-to-Point Circuits (Channels) (a) (b) (c) (d) (e) (f) Some possible topologies for a point-to-point subnet (a) Star (b) Loop (c) Tree (d) Complete (e) Intersecting loops (f) Irregular © 2006 by A-H. Esfahanian. All Rights Reserved.

Types of Design For Subnets… Sunday, April 16, 2017 Types of Design For Subnets… Broadcast Channels (a) (b) (c) Communication subnet using broadcasting (a) Bus (b) Satellite or Radio (c) Ring © 2006 by A-H. Esfahanian. All Rights Reserved.

Types of Design For Subnets… Sunday, April 16, 2017 Types of Design For Subnets… Broadcast Subnets May Allocate Channel By: Static Method TDMA Dynamic Methods Centralized Decentralized © 2006 by A-H. Esfahanian. All Rights Reserved.

Classification based on switching techniques Sunday, April 16, 2017 Classification based on switching techniques Circuit-switched networks A physical circuit must be established between the two communicating stations before any exchange of information. Packet-switched networks No physical circuit is established in advance. The message is stored and then forwarded at each intermediate node. © 2006 by A-H. Esfahanian. All Rights Reserved.