Computer Networks Chapter 0: Overview & Formalities

Transcription

1 Overview Computer Networks Chapter 0: Overview & Formalities Holger Karl Who are we? Research and teaching at Fachgebiet Rechnernetze The topic of Communication Networks Formalities Resources Exams Computer Networks Group Universität Paderborn 2 Who are we Fachgebiet Rechnernetze Prof. Dr. Holger Karl hkarl@ieee.org oder holger.karl@upb.de P Mittwoch, 9:00 10:00 Exercise Hermann Lichte Web page: Introduction of communication technologies Internet Zahl der angeschlossenen Haushalte in den Vereinigten Staaten (in Millionen) (Quelle: Bertelsmann) Radio Fernsehen Kabelfernsehen Internet/Online Internet today: About 1400 million users estimated (widely varying estimates) Fastest introduction time of any communication technology 3 4 1

2 A paradigm shift from voice to data Internet Usage statistics Machine-tomachine communication difficult to estimate, but will grow considerably in the future Source: Alcatel Telecommunication Review, % penetration 5 Mobile growth Mobile and Wireless Communication: Always Best Connected LAN, WLAN 780 kbit/s GSM 57 kbit/s Bluetooth 500 kbit/s UMTS, GSM 115 kbit/s LAN 100 Mbit/s, WLAN 54 Mbit/s UMTS, DECT 2 Mbit/s GSM 384 kbit/s, WLAN 780 kbit/s GSM 115 kbit/s, WLAN 11 Mbit/s Wireless, low-rate control networks 6 7 UMTS, GSM 384 kbit/s 8 2

3 The future of telecommunication systems UMTS, WLAN," DAB, GSM, " TETRA,..." ad hoc Personal Travel Assistant, DAB, PDA, Laptop, " GSM, UMTS, WLAN, " Bluetooth, IrDA, Intelligent Roadside by sensor networks..." 9 Communication/information is serious business Erwerbspersonen, Anteil in % Agrarzeitalter Industriezeitalter Informationszeitalter Informationen Dienstleistungen Produktion Landwirtschaft Quelle: L.A. Nefiodow: Der fünfte Kondratieff 10 A bit of communication history Year Innovation Issue 1840 Morse Telegraph Electrical exchange of data over larger distances 1861 Telephone (Reiss) One-way voice communication over larger distances 1870 Telephone (Bell) Bi-directional voice communication patented 1887 Electromagnetic waves (Hertz) Wireless communication possible 1892 Rotary dialer Automation of telephone switching 1923 Radio broadcast First electronic mass communication 1929 Coax cable Paves the way to higher data rates 1964 Communication satellites World-wide communication 1966 Optical fiber Leap forward in possible data rates 1984 De-regulation (US) End of state monopolies in telecommunication 1997 Wavelength division multiplexing Optical fibers can carry up to tera bits per second (1 tera = 10^12) Source: Schiller, Telematik, FU Berlin, Main research topics In general: architectures and protocols of communication systems Structure, design, performance evaluation, implementation, For all types of communication: computer networks, voice communication, data & multimedia content More specifically Future mobile and wireless communication What comes after GSM, UMTS, WLAN? Buzzwords: anybody, anytime, anywhere Cross-layer optimization Try to improve system by using all available sources of information Technical communication Wireless sensor (& actuator) networks Tiny devices to measure and control environment 12 3

4 Teaching FG Rechnernetze Topic of Computer Networks VIII VII VI V IV Ad hoc/ Sensornetze Mobilkommunikation Verteilte Systeme Rechnernetze KMS Leistungsbewertung/ Simulation Analysemethoden für Netze (Hannes Frey) Seminar Seminar Proseminar Projektgruppe Ever wondered what really happened after Typing into a Web browser? Making a phone call? How does data get from one device to another? Basic abstractions have been treated in KMS What happens behind the scene and on the wire? Communication systems enable this transport of data What are the necessary ingredients for such systems? Typical components? Are there any basic mechanisms to put such components together? To organize their working together? How can we cope with size, complexity, failures, user demands, in such systems? How to evaluate? Analysis? Simulation? Measurements? Tools? WS 10/11, v Legende: 1.5 Festnetz Computer Networks Drahtlos/mobil - Ch. 0: Overview and Formalities Methodik Topic of Computer Networks This lecture is about basic architecture and protocol mechanisms Attempts to give an overview of all important components Essentially, a round-up of all layers of ISO/OSI model For both data communication and voice / telecommunication It is NOT about specific technical solutions It is NOT about mobile and wireless communication Covered in Mobile Communication and Ad Hoc and Sensor Networks Requires Computer Networks as pre-requisite It is NOT about distributed systems Rather, builds the foundation for them to work Formalities Resources Slides are/will be available on the web site There will be NO script Secondary literature is necessary Mailing list, forum via PAUL! To give due credit where credit is due: Some of the material on these slides (text, pictures, graphs, pictograms, etc.) is used from lectures given by Profs. Krüger, Juling, Zitterbart, Schiller, Carle, Menth at the universities Karlsruhe, Braunschweig, FU Berlin, TU Munich, Würzburg Other parts are based on material available via the Internet, company presentations, and similar sources In particular, Tanenbaum s and Peterson/Davie s books online material Many thanks to everybody who contributed here and has graciously agreed to make their material available

5 Formalities Appointments This is a twice weekly, half-semester course! Lecture Tuesday 14:00 16:00, Room tba Wednesday, 14:00 16:00, Room tba Some lectures will be canceled; not clear yet, though Additional lecture: This Wednesday! Exercise Wednesday, 16:00 (s.t.?) 17:30, Room tba Assignments are on course web site Formalities Book recommendation Basic textbook for this class: A. Tanenbaum, Computer Networks, 4th edition, Prentice- Hall Classic textbook, excellent tutorial style, if occasionally a bit lengthy Do NOT use an earlier edition; they are partially outdated Do NOT use a translation Good command of English is necessary anyway For any updates check lecture, website and PAUL! Secondary book recommendations Another excellent book: William Stallings, Data and Computer Communications, 7th Edition, Prentice Hall A bit more technical, less chatty than Tanenbaum Secondary book recommendations L. L. Peterson & B. S. Davie, Computer Networks A Systems Approach, 2003, 3rd edition, Morgan Kaufman Rather technical approach, quickly gets down to how to build it questions Maybe a bit quick on the beginner, though J. F. Kurose & K. W. Ross, Computer Networking: A Top-Down Approach Featuring the Internet, 2004, 3rd edition, Addison Wesley Motivates why communication systems are built in a certain fashion by starting out from the applications that they should support

6 Further book recommendations F. Halsall: Data Communications, Computer Networks and OSI. Addison-Wesley, 4. Auflage, 1997 Similar to Tanenbaum, more details, particularly good for lower-layer questions Unfortunately, no longer updated S. Keshav: An Engineering Approach to Computer Networking. Addison-Wesley, 1999 Excellent book for fundamental treatments, some good theory chapters Also explains why some design choices are made Unfortunately, also a bit outdated Further book recommendations W.R. Stevens: TCP/IP Illustrated, Vol. 1-3, 1994, Addison-Wesley If you want to know everything about TCP/IP J. Schiller, Mobile communication, 2 nd edition, 2003, Addison Wesley Details on mobile communication Formalities Exam There will be a written exam Unless number of participants is too small, then oral examination Date, place, details to be announced Closed book, no additional material Both lecture and exercise material are relevant for the exam 23 6