810 likes | 1.1k Views
Mobile Computing. Lecturer: Prof. Huei-Wen Ferng Office: RB-503 URL: http://santos.ee.ntu.edu.tw/~wen. Chapter 0. Before the Course. Why and Who Will Be Mobile. Telecom Networks/Systems. Wired Networks (Internet) Local Area Networks (LANs) Public Data Networks, i.e., WANs
E N D
Mobile Computing Lecturer: Prof. Huei-Wen Ferng Office: RB-503 URL: http://santos.ee.ntu.edu.tw/~wen Prof. Huei-Wen Ferng
Chapter 0 Before the Course Prof. Huei-Wen Ferng
Why and Who Will Be Mobile Prof. Huei-Wen Ferng
Telecom Networks/Systems • Wired Networks (Internet) • Local Area Networks (LANs) • Public Data Networks, i.e., WANs • Wireless Networks • Wireless LANs • Mobile Data Networks • Fixed Telephone Networks, i.e., Public Switched Telephone Networks (PSTNs) • Mobile Phone Systems Prof. Huei-Wen Ferng
(1) Telephone (M) (2) Mobile phone (K) (3) Radio paging (K) (4) Internet (K) 12.04 (4.7%) 11,541 (144.0%) 3,873 (-9.1%) 2,874 (72.6%) 9.17 (7.9%) 770 (31.8%) 2,083 (20.5%) 21 10.01 (9.2%) 970 (26.0%) 2,301 (10.5%) 165 (686.0%) 10.86 (8.5%) 1,492 (53.8%) 2,641 (14.8%) 429 (160%) 11.50 (5.9%) 4,727 (217.0%) 4,261 (61.3%) 1,665 (288%) 12.64 (5.0%) 17,743 (53.7%) 2,867 (-26.0%) 4,650 (61.8%) Telecom Statistics 1995 1996 1997 1998 1999 2000 Note: According to Jan. 2001 statistics, total mobile phone subscribers are 18.3M in which CHT: 4.7M(25.7%), and others: 13.61M(74.3%) Prof. Huei-Wen Ferng
Some Forecasts • In 3 years, Internet traffic will grow to 10,000 times of its current level. • Global e-business revenue will grow 86% per year to $ 1.4 Trillion in 2003. • Bandwidth consumption will grow by a factor of 100 to 200 over the next four years. Prof. Huei-Wen Ferng
What is Mobile Computing? • Mobile Computing is also known as “Ubiquitous Computing” (anywhere, anytime, any device) • The scope covered by Mobile Computing roughly includes: Mobile Data, Wireless LANs and Ad Hoc Networks Prof. Huei-Wen Ferng
Mobile Computing Chart Verticals Horizontals Applications Operating systems Mobile operation systems Notebooks Phones Others Devices PDAs WANs LANs Wireless networks Prof. Huei-Wen Ferng
Application Layer • Vertical applications: those applied to a function part of an industry such as field sales and field service, or to specific market segment such as banking or health care • Horizontal applications: those applied to many people across most market segments Prof. Huei-Wen Ferng
Operation Systems Layer • This layer provides tools for application programmers to access different mobile devices and different wireless networks • A key layer to rapid growth of wireless networking and proliferation of applications Prof. Huei-Wen Ferng
Device Layer • All the mobile devices we carry with us: • Notebooks (NBs) • Personal Digital Assistants (PDAs) • Cellular phones • Personal communicators • Combination devices • Combination devices are now rapidly emerging Prof. Huei-Wen Ferng
Wireless Networks Layer • The Wireless Wide Area Network (WAN) is also called “Mobile Data” including: • Packet networks: RAM/Mobitex, ARDIS/Modacom • Paging networks • Data over cellular: CDPD (over AMPS), GPRS (over GSM) • Data over satellite • Wireless LANs: with much higher rate but smaller coverage than Mobile Data networks Prof. Huei-Wen Ferng
Applications Market by 2005 Prof. Huei-Wen Ferng
Field Sales Application • Sales quotation • Inventory check • Order entry • Credit authorization • Invoicing Prof. Huei-Wen Ferng
Field Service Application • Obtaining a maintenance history of the item requiring service • Performing complex diagnostics that require access to databases and applications at other locations • Checking parts inventory if required • Updating the maintenance database after the service is done • Invoicing for the job • Real-time dispatching of the field engineer Prof. Huei-Wen Ferng
Transportation Application • The oldest application • Including: • Automatically locating the vehicle • Dispatching the vehicle to the next job • Routing the vehicle if required • Capturing data from the vehicle Prof. Huei-Wen Ferng
Personal Communications Application • Messaging • Calendaring • Directories • Info Systems • Fax Prof. Huei-Wen Ferng
Mobile Office Application • Fax • E-mail • LAN access • File transfer • Database access Prof. Huei-Wen Ferng
Airlines Police Field sales Emergency Hospitals Maintenance Retail stores Stock exchanges Casinos Hotel Taxicabs Rental car agencies Transportation Vertical Market Examples Prof. Huei-Wen Ferng
Security User authentication Data privacy Privacy of user location Bandwidth Limited bandwidth (10K~10M) Software Still in its infancy The main/ biggest reason for late data implementations Safety Radiation is harmful to human beings Trends: low power, thus less radiation Challenges Prof. Huei-Wen Ferng
Horizontal Application Examples • Near term horizontal applications (LAN app.) • Dynamic work environment • Trade show • conference • Difficult to wire areas • New employees who need immediate service • Broad-based horizontal applications (WAN app.) • Wireless meeting • Wireless traveler • Interactive TV Prof. Huei-Wen Ferng
Positioning of Wireless Networking • Comparison between wireless data & wired data capacities • Position of wireless networks relative to wired networks: • Not a replacement but an extension to wired networks Prof. Huei-Wen Ferng
Evolution of Mobile Communication Systems Prof. Huei-Wen Ferng
Cellular Networks • North America: • 1G: • AMPS (Advanced Mobile Phone System); Analog • 2G • NAMPS; Analog • TDMA (IS-54, IS-136); Digital • CDMA (IS-95); Digital • 3G • IMT-2000 (International Mobile Telecommunications for the year 2000); Digital Prof. Huei-Wen Ferng
Cellular Networks • European • 1G • TACS (Total Access Communication System); Analog • NMT (Nordic Mobile Telephone); Analog; NMT-450, NMT-900 • 2G • GSM (Global System for Mobile Communications); Digital: GSM900, DCS1800, DCS1900 • 3G • UMTS (Universal Mobile Telecommunications Systems); Digital Prof. Huei-Wen Ferng
Cellular Networks • Japan • 2G • PDC (Personal Digital Cellular) • Germany • 1G • C-Nets • 2G • GSM Prof. Huei-Wen Ferng
Cordless Telephones • European • CT1, CT2 (Cordless Telephone, second generation) • DECT (Digital European Cordless Telecommunications) • America • PACS (Personal Access Communications System) • Canada • CT2Plus (CT2, enhanced version) • Japan • PHS (Personal Handyphone System) Prof. Huei-Wen Ferng
Packet Networks • RAM/Mobitex, • ARDIS/Modacom • TETRA (Trans European Trunked Radio System) Prof. Huei-Wen Ferng
Data over Cellular • CDPD (Cellular Digital Packet Data, over AMPS) • GPRS-136 (over IS-136 TDMA) • IS-95B (over CDMA) • HSCSD (High-Speed Circuit-Switched Data) • GPRS (General Packet Radio Service, over GSM) • EDGE (Enhanced Data Rates for GSM Evolution) • ECSD (Enhanced Circuit-Switched Data; circuit-mode) • EGPRS (Enhanced GPRS; packet-mode) Prof. Huei-Wen Ferng
Paging • Germany, France, Switzerland • Eurosignal in 1970s • Pan-European • ERMES (European Radio Message System) in 1992 Prof. Huei-Wen Ferng
Coverage and Bit Rate Prof. Huei-Wen Ferng
Migration Prof. Huei-Wen Ferng
2nd generation- Digital radio systems on circuit-switch telecom networks,low data speeds 2 Mbps 1st generation- Analog-based systems W-CDMA 3rd generation 384 kbps EDGE 115 kbps GPRS 57.6 kbps HSCSD 9.6 kbps GSM AMPS 2nd generation 1st generation 1985 1997 1999 2000 2001/2002 Evolving GSM Wireless Application Protocol Source: GSA,and TCC Evolution of Mobile Data 1.SMS Messaging 2.Web Mail 3.Information Services 4.Financial Services- Information Access 5.Financial Services - transactions 6.Mobile banking 7.Mobile Shopping 8.Internet Access Prof. Huei-Wen Ferng
GPRS OVERVIEW Prof. Huei-Wen Ferng
Inefficient use of radio resources Too complicated Too expensive Too slow No need packet switched transmission Emerging standards: MDI, WAP, Java PDA, Smart Phones Volume oriented accounting New coding schemes & channel combining Extensions of corporate, intranet, & internet applications Shared use of radio resources Trueplug & play Reasonable costs Comfortable speed Value added services Data Services : from GSM to GPRS Prof. Huei-Wen Ferng
GPRS : Main Improvements • Higher transmission rates • four new coding schemes allow different data rates ofCS-1 9.05 kbit/s, CS-2 13.4 kbit/s (in 10/00) CS-3 15.6 kbit/s, CS-4 21.4 kbit/s (in E/01) • channel combining • Increased radio resource efficiency • radio resources will be used only during data transmission • shared access of the same channel • Connection of GSM and IP world • Volume dependent charging • Faster session set-up • Always connected Prof. Huei-Wen Ferng
GPRS GSM Traffic Alert: Traffic Alert: Motorway A8 from München to Nürnberg congested Alternative route: leave motorway at X-Dorf and follow the orange signs Nürnberg Y-Dorf A8 X-Dorf München > > OK OK > > • User receives basically the same information, but with • GPRS better presentation of information possible • WAP over GSM is inefficient use of radio resources • WAP over GSM is too expensive • WAP over GSM is too slow WAP Migration from GSM to GPRS Prof. Huei-Wen Ferng
Application Service CapabilityServers Application Service GMSC/Transit HLR MSC SGSN SG Control Media Gateway/GGSN Media Gateway PSTN/ISDN Transport Backbone Element Backbone Element GSM InternetIntranets EDGE Backbone Element WCDMA Control User data Integration of 2G and 3G Prof. Huei-Wen Ferng
PSTN (Voice) SSS BSS Internet GPRS GSM&GPRS system WAP UTRAN U_MSC VPN 3G system Conceptual Network Architecture of GPRS / 3G Prof. Huei-Wen Ferng
3G Introduction Prof. Huei-Wen Ferng
The Third Generation Systems • Specifications: 3GPP WCDMA & 3GPP2 CDMA2000 • High data rate for Video transmission and networking • Main applications: audio & video phones、stock exchange、 e-mail、mobile banking、mobile Internet、e-maps、Information or news etc. Prof. Huei-Wen Ferng
Characteristics of 3G • Wideband CDMA • Multimedia applications • better audio quality • increased capacity • better bandwidth efficiency • high data rate • integration with 2G systems • global roaming Prof. Huei-Wen Ferng
Data Transmission Rate • Outdoor (rural): • maximum rate: 144 kbit/s • maximum speed 500 km/h • Outdoor (suburb): • maximum rate: 384 kbit/s • maximum speed 120 km/h • Indoor and Metropolitan: • maximum rate: 2 Mbit/s • maximum speed 10 km/h Prof. Huei-Wen Ferng
What are the Driving Forces ?Mobile Internet Services & Applications • CSD at 9.6 kbit/s • GPRS at 100 kbit/s • EDGE at 384 kbit/s • UMTS at 2 Mbit/s Downloading a 2MBytes music file 30 mn 3 mn 41 s 8 s Prof. Huei-Wen Ferng $2$
Conceptual Service Diagram Prof. Huei-Wen Ferng
Multimedia Services Prof. Huei-Wen Ferng
Voice and Data Markets Prof. Huei-Wen Ferng
Mobile and Internet Markets Prof. Huei-Wen Ferng
1800 Subscriptions worldwide (bn) Mobile subscriber 1600 Mobile Fixed Mobile Internet Fixed Internet 1400 1200 1000 Mobile internet subscriber 800 600 400 200 0 M-Business: Mobile and internet 1995 2000 2005 2010 Source: Ovum, ICN M CM Prof. Huei-Wen Ferng
3G Terminals Prof. Huei-Wen Ferng