Communication Networks

Transcription

1 Communication Networks Chapter 1 Introduction Winter 2017/18 Communication Networks - 1. Introduction 1 Overview Telegraphy Telephony Wireless Communications The Internet Mobile Communications Technical Communications: Machine to Machine Ubiquitous Computing Winter 2017/18 Communication Networks - 1. Introduction 2 Prof. Jochen Seitz 1

2 Communication Communication is the process of conveying information from a sender to a receiver with the use of a medium in which the communicated information is understood by both sender and receiver Communication requires that all parties understand a common language that is exchanged Winter 2017/18 Communication Networks - 1. Introduction 3 Communication in Detail Major dimensions to define communication: content (what type of things are communicated) source, emisor, sender or encoder (by whom) form (in which form) channel (through which medium) destination, receiver, target or decoder (to whom), purpose or pragmatic aspect Winter 2017/18 Communication Networks - 1. Introduction 4 Prof. Jochen Seitz 2

3 Telecommunication Telecommunication is the assisted transmission of signals over a distance for the purpose of communication In earlier times: smoke signals drums semaphores flags heliographs In modern times: electronic transmitters such as telephone, television, radio or computer Winter 2017/18 Communication Networks - 1. Introduction 5 Transmission System Three basic elements: a transmitter accepting information and converting it to a signal a transmission medium carrying the signal a receiver receiving the signal and converting it back into usable information Transmitter Receiver Transmission Medium Winter 2017/18 Communication Networks - 1. Introduction 6 Prof. Jochen Seitz 3

4 Abstract Model of a Telecommunication System Sender Receiver Service Interface Service Access Point Information (Abstract) Medium Spatial Distance Winter 2017/18 Communication Networks - 1. Introduction 7 Telecommunication Network Components telecommunication links nodes end nodes intermediate nodes Task forwarding of information from one end node to another (over multiple links and intermediate nodes) Examples local computer network public telephone network Internet Winter 2017/18 Communication Networks - 1. Introduction 8 Prof. Jochen Seitz 4

5 Communication Networks Winter Term 2017/18 Classes of Telecommunication Networks According to size GAN, WAN, MAN, LAN, CAN, PAN, According to provider public private ad-hoc infrastructure According to transported information According to physical medium wired/wireline wireless Winter 2017/18 According to organization and management analog digital According to main application telephony/voice automation multimedia data Communication Networks - 1. Introduction 9 Example of a Telecommunication Network Backbone LAN 1 Mobile Users URL Web Page Wireless LAN 3 Winter 2017/18 Prof. Jochen Seitz LAN 2 Communication Networks - 1. Introduction 10 5

6 Telegraphy Long-distance transmission of written messages without physical transport of letters Electrical telegraph developed and patented in the U.S. in 1837 by Samuel F. B. Morse Special encoding of message: Morse Code Transatlantic telegraph cable completed on July 18, 1866 Telegraph cable installed between London and Calcutta in 1870 (length approx. 10,000 km) Winter 2017/18 Communication Networks - 1. Introduction 11 Telephony Philip Reis ( ) Self-taught German scientist and inventor First working telephone in 1860/61 (Reis telephone) First public demonstration of the telephone on October 26, 1861 Alexander Graham Bell ( ) Eminent scientist, inventor and innovator Credited with the invention of the telephone Patent Number 174,465 issued to Bell on March 7, 1876, by U.S. patent office Winter 2017/18 Communication Networks - 1. Introduction 12 Prof. Jochen Seitz 6

7 The Success of Telephony Telegraphy was standard technique for telecommunication telephony disliked by telegraphy companies Telephony considered a toy the first services offered the transport of pieces of music or poems in 1880 Speech quality quite miserable in the beginning Communication via telephony considered impersonal and unreliable Telephony blamed for Black Friday in 1929 Winter 2017/18 Communication Networks - 1. Introduction 13 Wireless Telecommunications Guglielmo Marconi ( ) father of mobile communications applied the findings of the following scientists in practice Heinrich Hertz ( ) demonstration of electromagnetic waves in a lecture hall at University of Karlsruhe in 1988 Desiré Edouard Branly ( ) development of a receiver for radio communication Augusto Righi ( ) development of a sender for radio communication Winter 2017/18 Communication Networks - 1. Introduction 14 Prof. Jochen Seitz 7

8 Important Dates for Wireless Telecommunications 1896 Demonstration of wireless (digital) telegraphy by Guglielmo Marconi long wave radio transmission with very high transmission power (> 200 kw) 1907 Commercial wireless transatlantic communication large base stations (30 antenna masts, each 100 m high) 1915 Wireless telephony between New York and San Francisco 1920 Short wave radio brought forward by amateur radio operators 1926 Telephony in trains on the track from Hamburg to Berlin 1958 First cellular network (A-Netz) in Germany Winter 2017/18 Communication Networks - 1. Introduction 15 Birth of the Internet 1957 USSR s launch of sputnik American sputnik crisis 1958 Foundation of Advanced Research Projects Agency (ARPA) to expand the frontiers of technology and science Communication networks at that time: unreliable (star topology), proprietary and slow Proposed solution: robust and survivable packet switching (as opposed to circuit switching) 1969 Demonstration of the Internet on August 30: communication between UCLA and Stanford Research Institute Winter 2017/18 Communication Networks - 1. Introduction 16 Prof. Jochen Seitz 8

9 The First Message over the Internet Simply a LOGIN from the UCLA computer to the SRI computer: We sent an L - did you get the L? YEP! We sent an O - did you get the O? YEP! We sent a G did you get the G? CRASH!! Leonard Kleinrock (Source: Winter 2017/18 Communication Networks - 1. Introduction 17 Evolution of the Internet 1970 First Internet : 4 Hosts 1971 Start of the first Internet backbone (ARPAnet) with 15 nodes 1974 New protocol suite: TCP/IP (Transmission Control Protocol/Internet Protocol) 1988 Internet access from Germany: EUnet-IRB Dortmund XLink (extended Lokales Informatik-Netz) Karlsruhe 1989 Hypertext system created at CERN (European Organization for Nuclear Research at Geneva, Switzerland) birth of WWW 1991 EBONE: European backbone 1995 HotJava Web Browser by Sun attractiveness of programming language Java years of electronic mail ,739,698,500 Internet users world-wide (in March), almost 50% of the population Winter 2017/18 Communication Networks - 1. Introduction 18 Prof. Jochen Seitz 9

10 Billions Users of the Internet as of March World Population Source: Penetration of Internet Africa Asia Europe Latin America / Caribbean Middle East North America Oceania / Australia Winter 2017/18 Communication Networks - 1. Introduction 19 Mobile Data and Voice Traffic Source: news/cellular/ mobile-traffic-data-vsvoice.html Winter 2017/18 Communication Networks - 1. Introduction 20 Prof. Jochen Seitz 10

11 Subscribers [in Billions] Business Segments Security Telecommunication fixed line network providers mobile network providers cable TV providers T radio stations satellite network providers comm. equipment companies protocol designers Security Information Technology mainframe server PC pad/tablet cell phone software I T I M E S E Entertainment TV sets set-top boxes VCR cameras Hi Fi equipment game consoles M Security Media authors movie studios radio and TV broadcasts music industry publishers online games databases/cloud news / information services e-commerce Security Winter 2017/18 Communication Networks - 1. Introduction 21 Mobile Communications Anybody Anytime Anywhere Pacesetter: cellular mobile telephony more mobile users than fixed-line network users more subscribers than persons on Earth in 2015 Worldwide coverage All kinds of communication data speech multimedia Mobile Communication Subscriber Development Source: Worldwide-Cellphone-Subscriptions-Forecast-To-Exceed- Worldwide-Population-In-2015/ Year Winter 2017/18 Communication Networks - 1. Introduction 22 Prof. Jochen Seitz 11

12 Mobility and Globalization worldwide standardization anybody from anywhere at anytime PLMN (GSM, GPRS, EDGE, UMTS, IMT 2000, 3G, HSDPA, LTE, LTE+, 4G, 5G) wireless personal area networks (Bluetooth, ZigBee) wireless local area networks (IEEE , HIPERLAN) wireless multimedia i-mode WAP global village Internet in vehicles quality of service digital broadcast (DAB, DAB+, DVB-C/S/T) navigation location-based services voice over IP ubiquitous computing m-commerce Winter 2017/18 Communication Networks - 1. Introduction 23 Technical Communications Currently human beings involved in communication In the future machines directly communicate with each other Examples remotely controlled factories, Industry 4.0 vehicular communication (C2C, C2X, V2X, ) home automation (smart home) Winter 2017/18 Communication Networks - 1. Introduction 24 Prof. Jochen Seitz 12

13 Ubiquitous Computing Information Technology (IT) beyond the PC tablets/smart phones wearable devices wearable computing Enhanced environments access to information networks everywhere smart homes/buildings sensor networks Ubiquitous computing independent of a human user self-acting not perceptible pervasive computing Winter 2017/18 Communication Networks - 1. Introduction 25 Eras of Computing Mainframe Era one processor, many users PC Era one processor, one user Ubicomp Era one user, many processors Winter 2017/18 Communication Networks - 1. Introduction 26 Prof. Jochen Seitz 13

14 Revenue/ year Revenues According to Mark Weiser Mainframe (one processor, many users) PC (one processor, one user) Ubiquitous Computing (many processors, one user) Mark D. Weiser (July 23, 1952 April 27, 1999), the father of ubiquitous computing t Source: Winter 2017/18 Communication Networks - 1. Introduction 27 Converging Networks Speech Communication Entertainment Mobile and wireline communication infrastructure Internet Technical Communication Winter 2017/18 Communication Networks - 1. Introduction 28 Prof. Jochen Seitz 14

15 References Halsall, Fred (2000): Data Communications, Computer Networks and Open Systems. 4th edition, reprint. Harlow: Addison-Wesley (Electronic Systems Engineering Series). Kurose, James F.; Ross, Keith W. (2017): Computer Networking. A Top-Down Approach. 7th edition. Hoboken, New Jersey: Pearson. Peterson, Larry L.; Davie, Bruce S. (2012): Computer Networks. A Systems Approach. 5th edition. Amsterdam: Morgan Kaufmann (The Morgan Kaufmann Series in Networking). Stallings, William (2014): Data and Computer Communications. 10th edition. Upper Saddle River, N.J.: Pearson. Tanenbaum, Andrew S.; Wetherall, David J. (2011): Computer Networks. 5th edition. Boston: Pearson Prentice Hall. Winter 2017/18 Communication Networks - 1. Introduction 29 Prof. Jochen Seitz 15