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Politecnico di Milano Scuola di Ingegneria Industriale e dell’Informazione
Fundamentals of Communication Networks
Prof. Antonio Capone
Teacher o Prof. Antonio Capone o Office:
n Dip. di Elettronica, Informazione e Bioingegneria - DEIB
n 3° piano n stanza 335
o Tel: (02 2399) 3449 o E-mail: [email protected] o Web page:
n http://home.deib.polimi.it/capone/ o Office hours:
n Martedì 14.00-15.30
Exams
o Written and oral exam n 4 Numerical exercises n 1 Set of questions n Oral exam if written score >=15
Teaching material (1)
o Reference books: n A. S. Tanenbaum, D. J. Wetherall,
“Computer Networks”, Fifth Edition, Pearson n James F. Kurose, Keith W. Ross, “Computer
Networking: a top down approach”, Editore: Pearson
Teaching material (2)
o Other books n Saadawi Tarek N. , Ammar Mostafa H.,
El Hakeem Ahmed, “Fundamentals of telecommunication networks” Wiley
n Fred Halsall, “Data Communications, Computer Networks, and Open Systems” Addison-Wesley
n Behrouz A. Forouzan, TCP/IP protocol suite, McGraw-Hill
n Douglas E. Comer, Internetworking with TCP/IP, Addison-Wesley
Teaching material (3)
o Lecture slides o Other material and links o Course web site
Course home page
Course objetive
o Provide you the basics of computer networks
o Present you the “building blocks” of the Internet
This basic knowledge is fundamental for the advanced topics covered by most of the other courses of the MSc program
Background
Software applications exchange information with remote applications
For communicating they use: The INTERNET
Communications uses physical media and are subject to rules (protocols) o We will deal with:
n How to support communications n Protocols used at different layers n Network infrastructures
Probability Theory
o In addition to Communication Networks, the course provides also the basics of probability theory
o This is instrumental to some advanced course of networking like Traffic Theory, but also to other courses of the study program
Course program
o Basics of probability theory n Probabilities
o Definitions o Uniform spaces o Conditional spaces o Bayes’ Formulas o Statistical independence
n Random Variables o Spaces with infinite outcomes o Continuous Random Variables o Discrete Random Variables o Moments of a pdf o Conditional distributions and densities o Vectorial Random Variables o Functions of Random Variables
Course program
o Functional models n Protocols n Communication services n Stack models and main functions
o Physical layer n Multiplexing n Multiple access n Transport networks
o Link layer n Framing n Error control n Retransmission n Flow control n Link protocol example (HDLC)
Course program
o Local Area Networks n Random access n Ethernet n Bridging
o Internet architecture o Network layer: IP
n Addressing n Forwarding and routing n Control protocols n Routing protocols
Course program o Transport layer
n UDP n TCP
o Application layer n Name management: DNS n File transfer: FTP n Web Browsing: HTTP n E-mail: (SMTP) n Peer-To-Peer applications
o Private networks n Private addressing n Tunnels n NAT
o MPLS o IPv6
Politecnico di Milano Scuola di Ingegneria Industriale e dell’Informazione
Introduction
Fundamentals of Communication Networks
A bit of history
The born of the Internet: 60s
o 1961: Kleinrock – shows the effectiveness of packet switching with queuing theory
o 1967: Lawrence Roberts designs ARPAnet (Advanced Research Projects Agency)
o 1969: first network node IMP (Interface Message Processor) di ARPAnet at UCLA
The born of the Internet: 70s o 1972:
n NCP (Network Control Protocol) the first Internet protocol
n First email application n ARPAnet has 15 nodes
o 1970: n ALOHAnet radio packet
network at Univ. of Hawaii
o 1974: n Cerf and Kahn – design
internetworking (network of networks) principles
o 1976: n Ethernet is designed in
the Xerox labs o 1979:
n ARPAnet has 200 nodes
The born of the Internet: 80s
o 1982: SMTP for email is defined
o 1983: TCP/IP suite replaces NCP
o 1983: DNS is defined for mapping of names and addresses
o 1985: FTP protocol o 1988: congestion
control of TCP
o New national networks: Csnet, BITnet, NSFnet, Minitel
o 100.000 hosts
First applications
o Telnet o Email
o FTP
The born of the Internet: 90s o 1990: ARPAnet is
discontinued o 1991: NSF allows
commercial use of NSFnet
o First 90s: Tim Berners-Lee invents the web at Cern in Genève
o 1994: First browser Mosaic, then Netscape
o End of 90s: explosion of commercial use of the Web
The born of the Internet: 2000s
2000s: o New “killer
applications”: instant messaging, P2P file sharing, IP Telephony, social networks
o Network security o Billions of users o Link speeds up to
few Gbps Zuckerberg
Diffie-Hellman-Merkle
Shawn Fanning
The born of the Internet: 10s
10s - today: o Mobile internet o iPhone o Android o Application markets
http://www.caida.org
24
World is small
Internet growth
Jul 2013 996,230,757
Internet vs mobile networks
Per 100 inhabitants o 96 mobile subscribers o 16 fixed lines o 39 internet users o 10 fixed-broadband o 29 mobile-broadband
Source: ITU Data: 2012