Introduction to Computer Networking · Outline u General course information u Program u Preliminary schedule u Intro to computer networking: the entire course in one hour c 2005 Antonio

Introduction to Computer Networking

Antonio Carzaniga

Faculty of InformaticsUniversity of Lugano

March 8, 2005

c© 2005 Antonio Carzaniga

Outline

u General course information

u Program

u Preliminary schedule

u Intro to computer networking: the entire course in one hour


General Information

u http://www.inf.unisi.ch/carzaniga/edu/ntw05/


General Information


u AnnouncementsI http://www.inf.unisi.ch/carzaniga/edu/ntw05/news.htmlI you are responsible for reading the announcements page


General Information



u Office hoursI Antonio Carzaniga: Tue 15:00–16:00, Fri 15:00–16:00I Cyrus Hall: Tue 15:00–16:30, Fri 15:00–16:30I or by appointment


General Information



u Office hoursI Antonio Carzaniga: Tue 15:00–16:00, Fri 15:00–16:00I Cyrus Hall: Tue 15:00–16:30, Fri 15:00–16:30I or by appointment

u Open forum?I mailing list


Textbook

Computer Networking, a top down approach featuring the Internet3rd EditionJames F. Kurose and Keith W. RossAddison-Wesley

http://www.aw-bc.com/kurose-ross/


Evaluation

u +50% projectsI 3–5 assignmentsI grades added together, thus resulting in a weighted average

u +20% midterm exam

u +30% final exam

u ±10% instructor’s discretionary evaluationI participationI extra creditsI trajectoryI . . .


Evaluation Example

u +50% projectsI

6080 ; 80

120 ; 5570 ; 75

90 →270360 × 50% = 37.5%


Evaluation Example

u +50% projectsI

6080 ; 80

120 ; 5570 ; 75

90 →270360 × 50% = 37.5%

u +20% midterm examI

120150 →

120150 × 20% = 16%


Evaluation Example

u +50% projectsI

6080 ; 80

120 ; 5570 ; 75

90 →270360 × 50% = 37.5%


120150 →

120150 × 20% = 16%

u +30% final examI

180200 →

180200 × 30% = 27%


Evaluation Example

u +50% projectsI

6080 ; 80

120 ; 5570 ; 75

90 →270360 × 50% = 37.5%


120150 →

120150 × 20% = 16%

u +30% final examI

180200 →

180200 × 30% = 27%

u instructor’s discretionary evaluationI always late in class: −10%


Evaluation Example

u +50% projectsI

6080 ; 80

120 ; 5570 ; 75

90 →270360 × 50% = 37.5%


120150 →

120150 × 20% = 16%

u +30% final examI

180200 →

180200 × 30% = 27%

u instructor’s discretionary evaluationI always late in class: −10%

u TotalI 37.5% + 16% + 27% − 10% = 70.5% → 7


Plagarism

A student should never take someone else’s material and present itas his or her own. Doing so means committing plagiarism.


Plagarism


u “material” means ideas, words, code, suggestions, correctionson one’s work, etc.

u Using someone else’s material may be appropriateI e.g., software libraries.I always clearly identify the external material, and acknowledge its

source. Failing to do so means committing plagiarism.I the work will be evaluated based on its added value


Plagarism


u “material” means ideas, words, code, suggestions, correctionson one’s work, etc.

u Using someone else’s material may be appropriateI e.g., software libraries.I always clearly identify the external material, and acknowledge its

source. Failing to do so means committing plagiarism.I the work will be evaluated based on its added value

u Committing plagiarism on an assignment or an exam will result infailing that assignment or that exam

u Penalties may be escalated in accordance with the regulations ofthe Faculty of Informatics


Deadlines

Deadlines are firm.


Deadlines

Deadlines are firm.

u Exceptions may be granted

I at the instructor’s discretion

I only for documented medical conditions or other documentedemergencies


Deadlines

Deadlines are firm.

u Exceptions may be granted

I at the instructor’s discretion

I only for documented medical conditions or other documentedemergencies

u Each late day will reduce the assignment’s grade by one third ofthe total value of that assignment

I corollary: the grade of an assignment turned in more than twodays late is 0


Ethics

u From this course you can learn how toI eavesdrop network traffic (Web, e-mail, etc.)I forge network traffic (e.g., e-mail)I . . .

u This knowledge is essential to understanding networkedcommunications


Ethics

u From this course you can learn how toI eavesdrop network traffic (Web, e-mail, etc.)I forge network traffic (e.g., e-mail)I . . .

u This knowledge is essential to understanding networkedcommunications

u Nevertheless, abusing this knowledge is unethical—in fact, itmay be considered a crime


Example (the fun stuff)

webbrowser

webserver



webbrowser

webserver



webbrowser

webserver

GET /carzaniga/ HTTP/1.1

Host: www.inf.unisi.ch

. . .



webbrowser

webserver

HTTP/1.1 200 OK

. . .<html><head>. . . </head><body>. . .



webbrowser

webserver

GET /carzaniga/anto.png HTTP/1.1

Host: www.inf.unisi.ch

. . .



webbrowser

webserver

HTTP/1.1 200 OK

. . .

. . .


Streams or Packets?

webbrowser

webserver


Streams or Packets?

webbrowser

webserver


Streams or Packets?

webbrowser

webserver


Interconnections and Paths

webbrowser

webserver



webbrowser

webserver



webbrowser

webserver


Program (1)


Program (1)

u Introduction to networking and the Internet [4 hours]I the course in one lecture: a tour of all the topics of the course

through an end-to-end scenarioI the layered architectureI what is a protocolI basic network services: connection-oriented and connectionless

service; packet switching vs. circuit switchingI a bit of a historical perspective


Program (1)

u Introduction to networking and the Internet [4 hours]I the course in one lecture: a tour of all the topics of the course

through an end-to-end scenarioI the layered architectureI what is a protocolI basic network services: connection-oriented and connectionless

service; packet switching vs. circuit switchingI a bit of a historical perspective

u Application layer [16 hours]I the application interface: OS primitivesI a simple client/server programI the Web: HTTP; web cachingI e-mail: transfer protocol (SMTP); access protocols (POP and

IMAP); message format (MIME)I DNSI peer-to-peer networks


Program (2)

u Transport layer [8 hours]I multiplexing/demultiplexingI UDP: connectionless transport protocolsI principles of reliable data transferI principles of congestion controlI TCP: header format, reliability features, congestion-control

features.


Program (2)

u Transport layer [8 hours]I multiplexing/demultiplexingI UDP: connectionless transport protocolsI principles of reliable data transferI principles of congestion controlI TCP: header format, reliability features, congestion-control

features.

u Network layer [12 hours]I forwarding and routing for datagram and virtual-circuit servicesI general router architecture: interfaces, switching fabric, queuesI IP: header formats (IPv4 and IPv6), addressing, extensions,

fragmentation, IP forwardingI Routing algorithms and principles: link-state and distance vector

routing, hierarchical routingI IP Routing: OSPF, RIP, BGPI IP multicast


Program (3)

u Link layer [6 hours]I Multiple access protocolsI link-level reliability: error detection and error correctionI EthernetI Wireless links (802.11)I Integration with the network layer: link-layer addressing, ARP,

DHCP


Program (3)

u Link layer [6 hours]I Multiple access protocolsI link-level reliability: error detection and error correctionI EthernetI Wireless links (802.11)I Integration with the network layer: link-layer addressing, ARP,

DHCP

u Cross-layer Optional Topics [4 hours]I network management: principles, SNMP architecture and protocolI basic elements of communication security: block ciphers, modes

of operation, public-key cryptography, RSA, basics of TLS/SSLI proxies and tunnels


Introduction to Computer Networking · Outline u General course information u Program u Preliminary schedule u Intro to computer networking: the entire course in one hour c 2005 Antonio

Documents