移动互联网导论(第3版)课件1-intro

1、1Lecture 1Prof. Xinbing WangProf. Xiaohua TianWireless Communications and Mobile InternetDr. Xinbing Wang2Overview of the CourseWireless communication systems (Chapter 1)Flexibility to support roamingLimitations: Geographical coverage, transmission rate, and transmission errorsWireless communication

2、 technology Radio propagation (Chapter 5)Spread spectrum (Chapter 7)Current wireless systems Cellular network architecture (Chapter 10)Mobile IP (Chapter 12)Wireless LAN (Chapter 11)Other wireless networksSatellite systems (Chapter 9)Ad hoc networks (Reading materials)Sensor networks (Reading materi

3、als)Wireless PAN (Chapter 15)Dr. Xinbing Wang3OutlineBasicsArchitectures of wireless networksCellular network architectureSatellite systemsWireless LAN/PANAd hoc networksSensor networkBackgroundFDMA/TDMA/CDMAConnection setupDr. Xinbing Wang4TerminologyBase station (BS) or Access Point (AP): informat

4、ion distribution center for all mobile devices (MDs) within its signaling coverage area.Uplink (Reverse link): Radio channels from an MD to its serving BS/AP.Downlink (Forward link): Radio channels from the BS/AP to the MDs.Dr. Xinbing Wang5Current SituationWireless coverage in most highly populated

5、 areasInsufficient coverage, low system capacity, and low bandwidthNumerous overlapping, but incompatible wireless system as the obstacles for inter-system roaming.Dr. Xinbing Wang6Mbit/s1101000,1OutdoorFixedWalkVehicleIndoorFixed/DesktopWalkMobilityUMTSW-LANIEEE 802.11aHyperLAN2BluetoothGSM, IS-95,

6、 D-AMPSW BB- LANWide Area Network (WAN)- CoverageLocal Area Network (LAN)- Hot Spots - high speedPersonal Area Network (PAN)- Connectivity, cable replacementNew frequency allocations neededWireless Access: Range of Operation of Different TechniquesReference to S.R. Treves (Alcatel) presentation in M

7、obicom01.Rome Italy Dr. Xinbing Wang7Layer ArchitecturePhysical layerTransmission over the propagation channelsModulations, coding/decoding, interferences, multiplexing etc.Link layerRadio resource management such as power control, rate control, and error control.Network resource management such as

8、call admission control and service scheduling Networking layerHandoff managementLocation managementTraffic management Dr. Xinbing Wang8Influence of Mobile Communication to the Layer Modelservice locationnew applications, multimediaadaptive applicationscongestion and flow controlquality of serviceadd

9、ressing, routing, device locationhand-overauthenticationmedia accessmultiplexingmedia access controlencryptionmodulationinterferenceattenuationFrequencyApplication layerTransport layerNetwork layerData link layerPhysical layerDr. Xinbing Wang9Effects of Portability Power consumptionLimited computing

10、 power, low quality displays, small disks due to limited battery capacityCPU: power consumption Transceiver power consumptionLoss of dataHigher probability, has to be included in advance into the design (e.g., defects, theft)Limited user interfacescompromise between size of fingers and portabilityin

11、tegration of character/voice recognition, abstract symbolsLimited memorylimited value of mass memories with moving partsflash-memory as alternativeDr. Xinbing Wang10Difference from Wired NetworksHigher loss-rates due to interferenceemissions of, e.g., engines, lightningRestrictive regulations of fre

12、quenciesfrequencies have to be coordinated, useful frequencies are almost all occupiedLower transmission rateHigher delays, higher jitterconnection setup time with GSM in the second range, several hundred milliseconds for other wireless systemsLower security, simpler active attackingradio interface

13、accessible for everyone, base station can be simulated, thus attracting calls from mobile phonesAlways shared medium: secure access mechanismsDr. Xinbing Wang11 Cellular Networks Wireless LAN/MAN/PAN/Bluetooth Satellite Based GPS Home Networking Ad Hoc Networks Sensor Networks LTE, UWB, UMB, WiMAX,

14、etc The Internet of Things.Wireless Technology and Associated CharacteristicsDr. Xinbing Wang12First Generation Wireless Systems1970sDevelopments of radio and computer technologies for 800/900 MHz mobile communications1976WARC (World Administrative Radio Conference) allocates spectrum for cellular r

15、adio1979NTT (Nippon Telephone & Telegraph) introduces the first cellular system in Japan1981NMT (Nordic Mobile Telephone) 900 system introduced by Ericsson Radio System AB and deployed in Scandinavia1984AMPS (Advanced Mobile Phone Service) introduced by AT&T in North AmericaDr. Xinbing Wang13Second

16、Generation Wireless Systems1982CEPT (Conference Europeenne des Post et Telecommunications) established GSM to define future Pan-European Cellular Radio Standards1990Interim Standard IS-54 (USDC) adopted by TIA (Telecommunications Industry Association)1990Interim Standard IS-19B (NAMPS) adopted by TI

17、A1991Japanese PDC (Personal Digital Cellular) system standardized by the MPT (Ministry of Posts and Telecommunications)1992Phase I GSM system is operational1993Interim Standard IS-95 (CDMA) adopted by TIA1994Interim Standard IS-136 adopted by TIA1995PCS Licenses issued in North America1996Phase II G

18、SM operational1997North American PCS deploys GSM, IS-54, IS-951999IS-54: North America, IS-95: North America, Hong Kong, Israel, Japan, China, etc, GSM: 110 countriesDr. Xinbing Wang14Third Generation of Mobile Telecommunications1985Future Public Land Mobile Telecommunication System (FPLMTS) come up

19、 by ITU (International Telecommunication Union)1996Changed name to International Mobile Telecom System-2000 (IMT-2000)Enhanced Voice-Data Optimized (Ev-DO) was come up1998The first pre-commercial 3G network was launched by NTT DoCoMo in Japan, branded as FOMA2001FOMA is available as a teat of W-CDMA

20、UMTS (Universal Mobile Telecommunications System) based W-CDMA is opened in Europe2002The CDMA2000 system is standardized by 3GPP2 (3rd Generation Partnership Project 2)The CDMA-based 1xEV-DO technology in South Korea2006Fast low-latency access with seamless handoff orthogonal frequency division mul

21、tiplexing(Flash-OFDM) was developed2008Evolved HSPA(HSPA+) was releasedDr. Xinbing Wang15Fourth Generation of Mobile Telecommunications2006The pre-4G systemsMobile WiMAX occurred in South-Korea2008International Mobile Telecommunications Advanced (IMT-Advanced) specification was specified by ITU-R (T

22、he International Telecommunications Union-Radio communications sector)2009The technology proposals were submitted to the International Telecommunication Union (ITU) as 4G candidates2010First-release versions of Mobile WiMAX and LTE (Long Term Evolution) was recognized by ITU-R2011Mobile WiMAX Releas

23、e 2 (also known as WirelessMAN-Advanced or IEEE 802.16m) and LTE Advanced (LTE-A) are IMT-Advanced compliant backwards compatible versionsLTE-Advanced was standardized by 3GPP20124G systems fully compliant with IMT Advanced were standardized2013China-Mobile, China-Telecom, China-Unicom got the licen

24、ce of TD-LTEDr. Xinbing Wang165th Generation Wireless System2008NASA (National Aeronautics and Space) partnered with Geoff Brown and Machine-to-Machine Intelligence (M2Mi) Corp to develop 5G communications technologyThe South Korean IT R&D program of 5G mobile communication systems based on beam-div

25、ision multiple access and relays with group cooperation was formed2012The UK Government announced the setting up of a 5G Innovation Centre at the University of Surrey2013ITU-R Working Party 5D (WP 5D) started two study itemsSamsung Electronics stated that they have developed the worlds first 5G syst

26、em2014NTT DoCoMo start testing 5G mobile networks with Alcatel Lucent, Ericsson, Fujitsu, NEC, Nokia and SamsungBy now5G does not describe any particular specification in any official document published by any telecommunication standardization bodyDr. Xinbing Wang17InternetEarly 1960sResearch into p

27、acket switching startedEarly 1970sThe ARPANET led to the development of protocols for internetworking.1969The first two nodes were interconnected1974RFC 675 used the term internetas a shorthand forinternetworkingand laterRFCs repeat this use.1982the Internet Protocol Suite (TCP/IP) was standardizedL

28、ate 1980sCommercialInternet service providers(ISPs) began to emergeThe Internet started a rapid expansion to Europe and AustraliaEarly 1990sThe Internet started a rapid expansion to AsiaThe Internet was fully commercialized in the U.S.Mid 1990sThe rise of near instant communication by email, instant

29、 messaging, Voice over Internet Protocol (VoIP) phone calls, two-way interactive video calls, and the World Wide Web2011The estimated total number of Internet users was 2.095 billion (30.2% of world population)Dr. Xinbing Wang18Mobile Internet1971ALOHAnet connected the Hawaii islands with a UHF wire

30、less packet network1985The first access to the mobile web was commercially offered inFinland1991NCR CorporationwithAT&T Corporationinvented the precursor to 802.11 intended for use in cashier systems1996The Australian radio-astronomerJohn OSullivandeveloped a key patent used in Wi-Fi as a by-product

31、 in aCSIROresearch project1999The first commercial launch of a mobile-specific browser-based web service was in Japan wheni-modewas launched byNTT DoCoMoTheWi-Fi Allianceformed as a trade association to hold the Wi-Fi trademark200914 technology companies agreed to pay CSIRO $250 million for infringe

32、ments on CSIRO patents2012Approximately 10.5% of all Web traffic occurs through mobile devicesInternet and Mobile InternetDr. Xinbing Wang19 Impact of Mobile Internet 零售业 批发业 制造业 广告业 新闻业 通信业 物流业 酒店业/旅游业 餐饮业 金融业 保险业 医疗业 教育业 电视业 电影业 出版业 垄断行业 Dr. Xinbing Wang20Fundamentals of Cellular SystemsIllustrati

33、on of a cell with a mobile station and a base stationBSMSCellHexagonal cell area used in most modelsIdeal cell area (2-10 km radius)Alternative shape of a cellMSDr. Xinbing Wang21Location areaMSCVLRMobile Switching Center (MSC)(LA)Basic Architecture of Current Wireless SystemsPublic Switched Telepho

34、ne NetworkBase StationHLRHome Location Register (HLR)CellMobile Terminal (MT)MSCVLRCellVisitor Location Register (VLR)Dr. Xinbing Wang22Evolution to 3GGSMPDCcdmaOneTDMA(IS-136)GPRSEDGEcdma20003GToday 2G19.2kbps2000 evolved 2G64-115kbps3G115-384kbps | 0.384-2MbpsIMT-2000Capable SystemsNew SpectrumExi

35、sting SpectrumTDMA/GPRSTDMA/EDGEDr. Xinbing Wang23Time Schedule for 3G/4GJapan LaunchIMT-2000 Europe and SelectedRegions Open FirstNetworks CommerciallyGlobal Harmonization4G2001200220052010Dr. Xinbing Wang24End User needsInstant access to information servicesAnytime, Any Place, Any DevicePersonaliz

36、ed: “My Service, My Applications”Location-based: Relevant to wherever I ame-Commerce, m-CommerceAlways OnMobileMultimediaPersonalDr. Xinbing Wang253G Subscribers2G Digital only Subscribers1G Analogue only SubscribersSubscribers (100 millions)1990199119921993199419951996199719981999200020012002200320

37、04200520062007200820092010YearSubscriber Growth84121620 (8 China, 1.5US, 1.7 UK, 0.6 Japan)26Technology evolutionDr. Xinbing Wang27After ClassReading materialsIntroduction, chapter 1Transmission fundamentals, chapter 2Appendix 2AExercisesWhat is the main difference between wireless communications an

38、d wireline communications?What are the main functions of base stations/access points?What is FDMA/TDMA/CDMA?What is the current status of wireless networking?How different/similar of wireless networking and the Internet protocol stack/Dr. Xinbing Wang28Worldwide common frequency band & roamingAudio,

39、 video and data services including packet Data & multimedia Services High service quality and improved securityFlexible radio bearers for Bandwidth-On-Demand capabilities Distributed & coherent network managementCompatibility of services within IMT 2000Virtual home environment for servicesKey Featur

40、es and Objectives of 3G SystemsDr. Xinbing Wang29IMT-2000 (3G) SystemsIMT DS (Direct Sequence)(UTRAN FDD and W-CDMA)IMT MC (Multi-carrier)3G version of IS-95 (called cdmaOne) cdma2000IMT TC (Time Code) (UTRAN TDD)IMT SC (Single Carrier)Essentially a manifestation of GSM Phase2+ ( EDGE) IMT-2000 (Int

41、ernational Mobile Telecommunications-2000): Anywhere, anytime, anythingSixteen proposals are accepted to IMT-2000 systems family. Ten for terrestrial 3G networks, and six for MSSs (Mobile Satellite services) Dr. Xinbing Wang30W-CDMA (IMT-DS & TC):Developed by the 3G Partnership Project (3GPP)UTRA TD

42、D and UTRA-FDDBackers Ericsson, Nokia, NTT DoCoMo.Korea TTA II is similar to W-CDMAcdma2000 (IMT-MC): Compatible with IS-95Further developed by the 3G Partnership Project 2 (3GPP2)Backers Qualcomm, Lucent, and Motorola.Korea TTA I is similar to cdma2000 The most important IMT-2000 Systems IMT-DS and

43、 IMT-MCProposals for 3G StandardsDr. Xinbing Wang31Network Architecture of All-IP Wireless Networks Public Switched Telephone NetworkBGRouterVLRHLRBase Station/Node B/Access PointMobile Switching Center (MSC)/ServingGPRS Supporting Node (SGSN)Visitor Location Register (VLR)Home Location Register (HL

44、R)CellMobile Terminal (MT)LAs/RAsInternet BackboneBGRouterVLRMSC/SGSNBorder Gateway (BG)Dr. Xinbing Wang32Motivation for 4G SystemsIncrease bandwidth up to 100 Mbps.Smooth transition from existing systemsMake use of existing wireless infrastructure, even privately owned WLANs.Roaming has the key rol

45、e in the success of GSM. How about inter-system roaming?Serve the subscribers with required QoS Dr. Xinbing Wang33Whats new in 4GEntirely packet-switched networksAll elements are digitalHigher bandwidths to provide multimedia services at lower cost ( 100Mbit/s )High network security (security layer)

46、“Mobile multimedia to all at the same cost as fixed telephony today”Dr. Xinbing Wang34Comparison of 3G / 4G 3GBack compatibility to 2GCircuit and packet switched dataA combination of existing & evolved digital equipmentData rate2Mbps for fixed area384 kbps for indoor/outdoor and pedestrian144kbps fo

47、r vehicular 4GExtend the capacity of 3G by one order of magnitudeEntirely packet switched networksAll elements are digitalHigher bandwidth (100Mbps)宏基站微基站光纤覆盖面积：2公里 * 1.5公里 校园 （规模大：覆盖4万人校区）40个基站：14个宏基站，26个微基站 （技术先进：CRAN，8*8 MIMO （比美国LTE系统，Verison， AT&T），多层次结构，融合蜂窝与CMMB广播网络） LTE云蜂窝无线校园示范网络(R10)云蜂窝CRA

48、N 中心云蜂窝CRAN 中心3 CMMB 站址将于2012十月建设完成： Cellular-CMMB 混合网络系统LTE+CMMB云网络CMMB TransmitterDr. Xinbing Wang37OutlineBasicsArchitectures of wireless networksCellular network architectureSatellite systemsWireless LAN/PANAd hoc networks: MANETSensor networkBackgroundFDMA/TDMA/CDMAConnection setupDr. Xinbing W

49、ang38Traditional ApplicationsWeather satelliteRadio and TV broadcastingMilitary satellitesTelecommunication ApplicationsGlobal telephone connectionsBackbone for global networkGPSSatellite SystemsDr. Xinbing Wang39WLAN-Infrastructure NetworkStation (STA)terminal with access mechanisms to the wireless

50、 medium and radio contact to the access pointBasic Service Set (BSS)group of stations using the same radio frequencyAccess Pointstation integrated into the wireless LAN and the distribution systemPortalbridge to other (wired) networksDistribution Systeminterconnection network to form one logical net

51、work (EES: Extended Service Set) based on several BSSDistribution SystemPortal802.x LANAccess Point802.11 LANBSS2802.11 LANBSS1Access PointSTA1STA2STA3ESSDr. Xinbing Wang40WLAN - 802.11Advantagesvery flexible within the reception area (almost) no wiring difficulties (e.g. historic buildings, firewal

52、ls)more robust against disasters like, e.g., earthquakes, fire - or users pulling a plug. Ad-hoc networks without previous planning possibleDisadvantagestypically lower bandwidth compared to wired networks (1-54 Mbit/s)many proprietary solutions, especially for higher bit-rates, standards take their

53、 time (e.g. IEEE 802.11)products have to follow many national restrictions if working wireless, it takes a very long time to establish global solutions.Dr. Xinbing Wang41Ad hoc Network-802.11Direct communication within a limited rangeStation (STA):terminal with access mechanisms to the wireless medi

54、umBasic Service Set (BSS):group of stations using the same radio frequency. Sometimes called Independent BSS (IBSS) mode802.11 LANBSS2802.11 LANBSS1STA1STA4STA5STA2STA3Dr. Xinbing Wang42What is Mobile Ad hoc Network (MANET)?Mobile users with (compatible) wireless communication devices to set up a po

55、ssible short-lived networks-for a specific need/purpose!Without (necessarily) using a pre-existing infrastructureRoutes between nodes may potentially contain multiple hopsDr. Xinbing Wang43Model of OperationAssumption: the nodes are using IP, and they have IP addresses that are assigned by some mean

56、s.Dr. Xinbing Wang44MANET-Route ChangesMobility cause route changesDr. Xinbing Wang45Challenges in MANETLimited wireless transmission rangeBroadcast nature of the wireless mediumHidden terminal problemPacket losses due to transmission errorsMobility-induced route changesMobility-induced packet losse

57、sBattery constraintsPotentially frequent network partitionsEase of snooping on wireless transmissions (security hazard)Dr. Xinbing Wang46Comparison of Ad Hoc and Infrastructure NetworkScalabilityAd Hoc: (1) expansion is limited to the coverage of the radio transmitter and receiver for single-hop net

58、works; (2) No simple way to scale up the network coverage or capacity; (3) The potential coverage of the network is increased, but the traffic handling capacity remains the same; (4) use proxy servers with a wireless connection to the backbone wired networks.Infrastructure network: by increasing the

59、 number of base stations or access points, the coverage and the capacity will be increased. It is used for wide area coverage and for variable traffic loads.Dr. Xinbing Wang47Comparison of Ad Hoc and Infrastructure Network (2)FlexibilityAd Hoc network: flexible and can be se up instantly, it is used

60、 for temporary applications.Infrastructure network: time-consuming and expensive for good design.Controllability: time synchronization, power control, authentication and so on.Ad hoc: requires complicated structures demanding changes in all terminals.Infrastructure: all features are implemented in B