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CSE401NComputer Networking

January 2006

S. M. Hasibul HaqueDepartment of Computer Science

BUET

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What is this course about?

Introductory (first!) course in computer networking

learn principles of computer networking learn practice of computer networking Internet architecture/protocols as case study

• by the time you are finished ……

Goals: learn a lot (not just factoids, but principles and

practice) have fun (well, it should be interesting, at least)

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Course Information

Who is this course for? Undergrads

Prerequisites: Algorithms, Operating Systems, programming skills

Course materials: text: Computer Networking: A Top Down Approach

Featuring the Internet, J. Kurose & Keith Ross, Addison Wesley, 2000

WWW readings Class notes

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Administrative trivia’s Textbook

Computer Networking: A Top-Down Approach Featuring the Internet, 2/e by Kurose and Ross

Reference books Computer Networks, 4/e by

Andrew S. Tanenbaum Computer Networks, A system

approach. 3/ed by Larry L. Paterson

Unix Network Programming by W. Richard Stevens

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Course Information (more)

Broadcast email: cse401n_jan06@yahoogroups.com more later

Personnel instructor

• S. M. Hasibul Haque • hasibulhaque@cse.buet.ac.bd• Hasibul_haque@yahoo.com• office hours

– Feel free to stop by if you see me.– e-mail is the best way to communicate with me

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What Are the Goals Of This Course?

Understand the Computer Network

Understand how Internet works Its philosophy Its protocols and mechanisms

Learn Network Programming

Have fun!

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What Will We Cover?

Internet architecture and design philosophy applications

HTTP, Email, DNS,P2P, NP transport services

reliability; congestion control; transport protocols: TCP/UDP network services

routing; network protocols: IP/IPv6 link and physical layers

multiple access; Ethernet, FDDI, hubs and bridges multimedia networking

audio/video applications; network support network security

security primitives; BAN logic, SSL network management

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What Do You Need To Do?

Your prerequisites algorithms: e.g. shortest path algorithms programming: C/C++, or Java basic concepts of operating systems

Your workload Homework assignments

• programming assignments 4 class tests (on Saturday)

• CT-1: 4rd week• CT-2: 7th week• CT-3: 9th week• CT-4: 13th week• No additional notices of CT will be given.• If SAT is OFF then CT on Next Available Class.

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Course Overview:

Part 1: Introduction (text: Chapter 1) What is the Internet, What is a protocol? Network edge, network core, network access Physical media Delay, loss in packet-switched networks Protocol layers, service models Internet backbones, NAPs and ISPs A brief history of networking, Internet

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A top-down approach:

We’ll cover networking top-down

end-system applications, end-end transport

network core: routing, hooking nets together

link-level protocols, e.g., Ethernet

other stuff: security, management, multimedia

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Course Overview:

Part 2: Application Layer (text: Ch. 2) Principles of application-layer protocols The World Wide Web: HTTP File transfer: FTP Electronic mail in the Internet The Internet's directory service: DNS Socket programming PROGRAMMING ASSIGNMENT

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Course Overview:

Part 3: Transport Layer (text Ch. 3) Transport-layer services and principles Multiplexing and demultiplexing applications Connectionless transport: UDP Principles of reliable of data transfer TCP case study PROGRAMMING ASSIGNMENT Principles of congestion control TCP congestion control

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Course Overview:

Part 4: Network Layer (text: Ch. 4) Introduction and network service model Routing principles PROGRAMMING ASSIGNMENT Hierarchical routing IP: the Internet Protocol Routing in the Internet What’s inside a router? Mobile networks

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Course Overview:

Part 5: Link Layer, LANs (text: Ch. 5) Introduction, services Error detection, correction Multiple access protocols, LANs LAN addresses, ARP Ethernet Hubs, bridges, switches Wireless LANs: IEEE 802.11 PPP: the Point-to-Point protocol ATM networks

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Course Overview:

Part 6: Network Security (text: Ch. 7) What is network security? Principles of cryptography Authentication: Who are you? Integrity Key distribution, certification Firewalls Attacks, countermeasures Case studies: secure e-mail, SSL, IPsec, 802.11

WEP

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Course Overview:

Part 7: Network Management (text: Ch. 8) What is Network Management? Internet Network Management Framework, SNMP ASN.1

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Course Overview:

Part 8: Multimedia Networking (time permitting, text: Ch. 6)

Multimedia Networking Applications Streaming Stored Audio and Video Making the Best of the Best-Effort Service Beyond Best Effort Scheduling and Policing Mechanisms Integrated Services RSVP Differentiated Services

FINAL EXAM

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Outline

Administrative trivia’s What is the Internet?

Nuts-and-bolds Description Service Description What is a Protocol?

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What’s the Internet: “nuts and bolts” view

millions of connected computing devices: hosts, end-systems pc’s workstations, servers PDA’s phones, toasters

running network apps communication links

fiber, copper, radio, satellite==Bandwidth (bps)

routers: forward packets (chunks) of data thru network

local ISP

companynetwork

regional ISP

router workstation

servermobile

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“Cool” internet appliances

World’s smallest web serverhttp://www-ccs.cs.umass.edu/~shri/iPic.html

IP picture framehttp://www.ceiva.com/

Web-enabled toaster+weather forecasterhttp://dancing-man.com/robin/toasty/

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What’s the Internet: “nuts and bolts” view

Route: series of communication links and routers

ISP: End system access the Internet thru ISP

Protocol: each end system, routers and other “pieces” of the Internet run protocol that controls communication.

local ISP

companynetwork

regional ISP

router workstation

servermobile

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What’s the Internet: “nuts and bolts” view protocols: control sending,

receiving of msgs e.g., TCP, IP, HTTP, FTP, PPP

Internet: “network of networks” loosely hierarchical public Internet versus private

intranet

Internet standards RFC: Request for comments IETF: Internet Engineering

Task Force

local ISP

companynetwork

regional ISP

router workstation

servermobile

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What’s the Internet: a service view communication

infrastructure enables distributed applications: WWW, email, games, e-

commerce, database., voting, file (MP3) sharing

communication services provided: connectionless connection-oriented

cyberspace [Gibson]:“a consensual hallucination experienced daily by

billions of operators, in every nation, ...."

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What’s a protocol?human protocols: “what’s the time?” “I have a

question” introductions… specific msgs sent… specific actions

taken when msgs received, or other events

network protocols: machines rather

than humans all communication

activity in Internet governed by protocols

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What’s a protocol?

all communication activity in Internet governed by protocols

A network protocol defines the formatand the order of messages exchangedbetween two or more communicatingentities, as well as the actions taken onthe transmission and/or receipt of amessage or other event.

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What’s a protocol?a human protocol and a computer network protocol:

Q: Other human protocol?

Hi

Hi

Got thetime?

2:00

TCP connection req.

TCP connectionreply.Get http://www.buet.ac.bd/index.htm

<file>time

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End of Class

Be Patient! Lots of Real Life Scenario. Ref:

K/R-1.1