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Computer Networks 2Prepared by

Nguyễn Đức Thái

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Course Details

Time allocation per week:3 lecture hours for theory2 lecture hours for exercises and lab work8 hours for self-study

E-mail: thai@cse.hcmut.edu.vnWebsite: http://www.cse.hcmut.edu.vn/~thai

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Course Outline

Chapter 1: Computer Networks ReviewChapter 2: Implementation of TCP/IP ProtocolsChapter 3: Switching and RoutingChapter 4: WAN and PortalsChapter 5: Wireless NetworksChapter 6: Multimedia and Quality of Services

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Course Outline

Chapter 7: Network AdministrationChapter 8: Network Security

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References[1] “The Illustrated Network”, Walter

Goralski, The Morgan Kaufmann, 2009 [2] “Computer Networks: A system approach”, Larry L.

Peterson and Bruce S. Davie, 3th Edition, The Morgan Kaufmann, 2003

[3] “Data Communications and Networking”, Fourth Edition, Behrouz A. Forouzan, Mc Graw-Hill International Edition, 2007

[4] “Wireless Communications And Networking”, VijayK. Garg, The Morgan Kaufmann, 2007

[5] “TCP/IP Guide”, Charles M. Korzierok, ElectronicBook, 2005

[6] “Computer Networks”, Andrew S. Tanenbaum, 4th Edition, Prentice Hall, 2003

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Assessment

Lab work and assignment: 20%Midterm exam: 30%

Multiple-choice questions: 60 minutes

Final exam: 50%Multiple-choice questions: 90 minutes

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Layers: Describe Data Comm.

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OSI Reference Model

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Relationship of OSI Layers

PhysicalCommunication

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Relationship of OSI Layers

PhysicalCommunication

interface

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Relationship of OSI Layers

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Layer Functions

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Encapsulation / De-encapsulation

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Encapsulation / De-encapsulation

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Physical Layer

Appl.

Pres.

Sess.

Tran.

Netw.

Data.

Phys.

Appl.

Pres.

Sess.

Tran.

Netw.

Data.

Phys.

Define how cable is attached to the Network Adapter Card.Responsible for transmitting bits from one computer to another.

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Physical Layer

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Data-Link Layer

Makes data framesProvides an error-free communication link

Appl.

Pres.

Sess.

Tran.

Netw.

Data.

Phys.

Appl.

Pres.

Sess.

Tran.

Netw.

Data.

Phys.

10110110101 01100010011 10110000001

frame

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Data-Link Layer

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Data-Link Layer

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Network Layer

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Network Layer

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Transport Layer

Reliable process-to-process delivery of a msg

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Transport Layer

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Session Layer

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Presentation Layer

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Application Layer

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Summary of Layers

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TCP/IP Protocol Stacks

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Addresses in TCP/IP

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Addresses in TCP/IP

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Protocols

Protocol:a set of rules that determines all aspects of data communications

Protocol definessyntax, semantic and synchronization, control,...

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Protocol SpecificationsPhysical connection, signalingHandshaking, authenticationNegotiation of parametersMessage delimitersMessage formatError detectionError correctionTermination of communications

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Who Defines a Protocol? Anyone!

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Standard Administration

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Internet Administration

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Internet Admin. Organizations

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Communication Models

Client-Server ModelPeer-to-peer Model

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Client-Server ModelServer

always-on hostpermanent IP addressserver farms for scaling

Clientcommunicate with servermay be intermittently connectedmay have dynamic IP addressesdo not communicate directly with each other

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Peer-to-Peer Model

Architectureno always-on serverarbitrary end systems directly communicatepeers are intermittently connected and change IP addresses

Advantage-DisadvantageHighly scalable but difficult to manage

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References

Illustrated pictures taken from the Internet