Introduction to Computer Networking · Outline u General course information u Program u Preliminary...
Transcript of Introduction to Computer Networking · Outline u General course information u Program u Preliminary...
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
c© 2005 Antonio Carzaniga
General Information
u http://www.inf.unisi.ch/carzaniga/edu/ntw05/
c© 2005 Antonio Carzaniga
General Information
u http://www.inf.unisi.ch/carzaniga/edu/ntw05/
u AnnouncementsI http://www.inf.unisi.ch/carzaniga/edu/ntw05/news.htmlI you are responsible for reading the announcements page
c© 2005 Antonio Carzaniga
General Information
u http://www.inf.unisi.ch/carzaniga/edu/ntw05/
u AnnouncementsI http://www.inf.unisi.ch/carzaniga/edu/ntw05/news.htmlI you are responsible for reading the announcements page
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
c© 2005 Antonio Carzaniga
General Information
u http://www.inf.unisi.ch/carzaniga/edu/ntw05/
u AnnouncementsI http://www.inf.unisi.ch/carzaniga/edu/ntw05/news.htmlI you are responsible for reading the announcements page
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
c© 2005 Antonio Carzaniga
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/
c© 2005 Antonio Carzaniga
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 . . .
c© 2005 Antonio Carzaniga
Evaluation Example
u +50% projectsI
6080 ; 80
120 ; 5570 ; 75
90 →270360 × 50% = 37.5%
c© 2005 Antonio Carzaniga
Evaluation Example
u +50% projectsI
6080 ; 80
120 ; 5570 ; 75
90 →270360 × 50% = 37.5%
u +20% midterm examI
120150 →
120150 × 20% = 16%
c© 2005 Antonio Carzaniga
Evaluation Example
u +50% projectsI
6080 ; 80
120 ; 5570 ; 75
90 →270360 × 50% = 37.5%
u +20% midterm examI
120150 →
120150 × 20% = 16%
u +30% final examI
180200 →
180200 × 30% = 27%
c© 2005 Antonio Carzaniga
Evaluation Example
u +50% projectsI
6080 ; 80
120 ; 5570 ; 75
90 →270360 × 50% = 37.5%
u +20% midterm examI
120150 →
120150 × 20% = 16%
u +30% final examI
180200 →
180200 × 30% = 27%
u instructor’s discretionary evaluationI always late in class: −10%
c© 2005 Antonio Carzaniga
Evaluation Example
u +50% projectsI
6080 ; 80
120 ; 5570 ; 75
90 →270360 × 50% = 37.5%
u +20% midterm examI
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
c© 2005 Antonio Carzaniga
Plagarism
A student should never take someone else’s material and present itas his or her own. Doing so means committing plagiarism.
c© 2005 Antonio Carzaniga
Plagarism
A student should never take someone else’s material and present itas his or her own. Doing so means committing plagiarism.
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
c© 2005 Antonio Carzaniga
Plagarism
A student should never take someone else’s material and present itas his or her own. Doing so means committing plagiarism.
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
c© 2005 Antonio Carzaniga
Deadlines
Deadlines are firm.
c© 2005 Antonio Carzaniga
Deadlines
Deadlines are firm.
u Exceptions may be granted
I at the instructor’s discretion
I only for documented medical conditions or other documentedemergencies
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
Example (the fun stuff)
webbrowser
webserver
c© 2005 Antonio Carzaniga
Example (the fun stuff)
webbrowser
webserver
c© 2005 Antonio Carzaniga
Example (the fun stuff)
webbrowser
webserver
GET /carzaniga/ HTTP/1.1
Host: www.inf.unisi.ch
. . .
c© 2005 Antonio Carzaniga
Example (the fun stuff)
webbrowser
webserver
HTTP/1.1 200 OK
. . .<html><head>. . . </head><body>. . .
c© 2005 Antonio Carzaniga
Example (the fun stuff)
webbrowser
webserver
GET /carzaniga/anto.png HTTP/1.1
Host: www.inf.unisi.ch
. . .
c© 2005 Antonio Carzaniga
Example (the fun stuff)
webbrowser
webserver
HTTP/1.1 200 OK
. . .
. . .
c© 2005 Antonio Carzaniga
Streams or Packets?
webbrowser
webserver
c© 2005 Antonio Carzaniga
Streams or Packets?
webbrowser
webserver
c© 2005 Antonio Carzaniga
Streams or Packets?
webbrowser
webserver
c© 2005 Antonio Carzaniga
Interconnections and Paths
webbrowser
webserver
c© 2005 Antonio Carzaniga
Interconnections and Paths
webbrowser
webserver
c© 2005 Antonio Carzaniga
Interconnections and Paths
webbrowser
webserver
c© 2005 Antonio Carzaniga
Program (1)
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
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.
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga
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
c© 2005 Antonio Carzaniga