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Introduction to Communication Systems

March – June 2006

Dr. P. Papadimitratos and Prof. J-P. Hubaux

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Exchanging Information

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Mobile Cellular Telephony

Exponential Growth

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The Internet

TCP/IP

FTP

HTTP

SMTP

SSL

E-CommerceSearch EnginesFile Sharing

Voice-over-IPVideo

Streaming

Email

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The Internet (cont’d)

Movie is available here (62MB!):http://www.caida.org/publications/presentations/Ietf199712/Movie/movie.mpg

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The Internet (cont’d)

Interconnected Packet Switching Networks

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The Internet (cont’d)

Topologies of interconnected systems

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The Internet (cont’d)

Exponential Growth

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Wi-Fi: The Internet goes Wireless

Handheld

Laptop

Scanner

PDA

Wireless Access Point

Gateway to the Internet

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Pervasive Internet: Mobile Ad Hoc Networks

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Pervasive Internet: Vehicular Networks

ad ho

c

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Pervasive Internet:Sensor Networks

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The Interplanetary Internet

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An Ad Hoc Network in the Interplanetary Internet

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The Whole Picture

Wide area

Metropolitan area

Campus-wide

In-house

verticalhand-over

horizontalhand-over

Integration of heterogeneous fixed and mobile networks with varyingtransmission characteristics

Sensor Field

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2005 - 2015 : A Decade of New Challenges

Technical challenges– Dependability– Security– Mobility– Scalability– …

Global challenges:– Lack of manpower– Trend toward concentration– Usability– Privacy– …

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Challenge Example 1:Scalability - Ad Hoc network throughput

If we have:- identical randomly located nodes- each capable of transmitting bits/sThen the throughput ( ) obtainable by each node for a destination is

( )log

nW

nrandomly chosen

Wnn n

λ

λ⎛ ⎞

= Θ ⎜ ⎟⎜ ⎟⎝ ⎠

Ref: P. Gupta, P. Kumar, The Capacity of Wireless Networks IEEE Transactions on Information Theory, March 2000

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Challenge Example 2:Network Security - Viruses

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Communication Systems: a Scientific Discipline and

a Profession

Basestation

Mobilestation Server

Signal Processing

System Programming

Telecommunications

Networking

DistributedInformationSystems

Information TheoryTheory of Algorithms

Security

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Seminar Schedule

http://http://lcawww.epfl.ch/papadimitratos/CSS/index.htmllcawww.epfl.ch/papadimitratos/CSS/index.html

Credits for data, movie, and pictures

JPL

CAIDA.ORG

http://lcawww.epfl.ch/papadimitratos/CSS/index.html

Introduction to �Communication Systems��March – June 2006Exchanging InformationMobile Cellular TelephonyThe InternetThe Internet (cont’d)The Internet (cont’d)The Internet (cont’d)The Internet (cont’d)Wi-Fi: The Internet goes WirelessPervasive Internet: �Mobile Ad Hoc NetworksPervasive Internet: �Vehicular NetworksPervasive Internet:�Sensor NetworksThe Interplanetary InternetAn Ad Hoc Network �in the Interplanetary InternetThe Whole Picture2005 - 2015 : A Decade of New ChallengesChallenge Example 1:�Scalability - Ad Hoc network throughputChallenge Example 2:�Network Security - VirusesCommunication Systems: �a Scientific Discipline and �a ProfessionSeminar Schedule