MOB 1 intro 2010 lập trình mobi

 Computers are more and more integrated – small, cheap, portable, replacable - no more separate devices  Technology is in the background – computer are aware of their environment

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Internet & Mobile Communications

Master 1 - Spring 2010

MI 021

Ho Chi Minh Ville

Anne Fladenmuller Assistant Professor – UPMC (France)

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  frequencies & regulations

  signals, antennas, signal propagation

–  Wireless LANs

  Basic Technology

–  Wireless PANs

  IEEE 802.11a/b/g, 15, Bluetooth

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Internet & Mobile Communications - 2010

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Bibliography

  Course mostly based on

–  the book :

  "Mobile Communications", Addison-Wesley de Jochen Schiller

–  Other reference books :

  « Data and computer communications », William Stallings

  « Réseaux de mobiles et réseaux sans fil » Khaldoun Al Agha, Guy Pujolle, Guillaume Vivier

  « Wi-fi par la pratique», Guy Pujolle, Davor Malès

–  Several Tutorials :

  Vadia Nitin

  Gwendal Le Grand

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Computers for the next decades?

  Computers are more and more integrated

–  small, cheap, portable, replacable - no more separate devices

  Technology is in the background

–  computer are aware of their environment and adapt (“location awareness”)

–  computers recognize the location of users and react appropriately (e.g., call forwarding, fax forwarding, “context awareness”))

  Advances in technology

–  more computing power in smaller devices

–  Heterogeneous devices and diverse capacities

–  flat, lightweight displays with low power consumption

–  new user interfaces due to small dimensions

–  more bandwidth per cubic meter

–  multiple wireless interfaces: wireless LANs, wireless PANs, wireless WANs, regional wireless telecommunication networks etc (“overlay networks“)

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Number of wireless clients in the world

Market of mobile telephony between 1999

and 2003

050100150200250300350

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Wifi chips

  The number of Wifi chips sold in 2008 reached 387 millions

of unit for all market areas

+ 52% for the Wi-Fi telephony market

+ 51 % for the printing market

+ 23% for the notebook, laptops (144 millions unit)

+ 33% for the mobile devices market (MID, camera, audio players , video players …) (71 millions unit)

Stable for the game market, set-top-boxes,…

According to the Wi-Fi Alliance and In-Stat, the increase should reach 12% for laptop market

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  In 2010, ABI foresees more than 109 000 Wi-Fi AP for this particular

–  Promissing commercial benefits before the effective use of Wimax technologies

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Vietnamese Market

  German market research group, GFK predicted in 2008 that

around 320,000 laptops ought to be sold in Vietnam for that year, doubling that of 2007

  HCM City currently has around five providers of wireless services

–  FPT Telecom is the most outstanding player with a US$1.5 million project to develop a Wifi city initiated in June 2007

–  Telecom’s wireless Internet services now cover most banks, hotels and

luxurious restaurants in inner HCM City (5,000 points)

–  Viettel Mobile has begun testing wireless Internet services by providing free services in some districts in Hanoi and HCM City

–  Two CDMA-based mobile networks, S-Fone and EVN Telecom, are

implementing wireless Internet services

No standard wireless model though Wifi is praised for its business potentials, telecom firms are hesitating to develop Wifi Most of

them are just testing services

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Vietnamese Market

  Operator’s view

–  “After an experimental period, we see space barriers and we are seeking better solutions for these,” said Viettel’s Deputy Director in charge of technology, Hoang Son

–  S-Fone’s wireless Internet service for mobile phone is praised for its good quality but the charges are still high

–  For EVN Telecom, though the service is wireless, users have to use

a slow dial-up connection

  Security is a problem for wireless Internet services as it is said that hackers can attack computers through Wifi

system

–  Some service providers have warned that as wireless services in Vietnam are in a trial period and there is no standard security model users must protect themselves

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Wireless telephony in France

–  Autorité de régulation des télécoms (Arcep)

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Increased number of smartphones

MI021 – « Internet Mobile et Ambiant » - 2010

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Wireless in the world

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Long Term Evolution

  Average annual growth rate (conseil Pyramid Research)

–  Motorola : + 404 % between 2010 and 2014, –  Estimation of 136 millions of subscribers by the end of 2014 (growth of UMTS/HSPA subscribers was of 100 millions in 6 years)

  Goal: transfert of high speed data with a longer transmission range,

higher number of user per cell and lower latency

USA/ Sweeden/ … : An offer is set up for 2010 (Ericsson : HSPA (3G) network

with very high speed (84 Mbits/s) over Danemark other major cities in Sweeden before the end of 2010)

France : Arcep (Autority dof regulation of communications) : Licences

allocated in 2010 and sold in 2011

- Sprectrum of 2,6 GHz Band (military) should be freed by 2010 and 2012

- Spectrum of 800 MHz Band (television and army) freed by december 2011

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Internet Market

MI021 – « Internet Mobile et Ambiant » - 2010

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Internet Market

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Commercial Wifi market

  In 2011, South Pacific should overtake Europe and America in terms of number

  Hotels: First user ofe WiFi in the world Promissing market since VoIP is

– 

 

  Promissing market, until LTE/WiMAX is being deployed ?

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WiMAX (Worldwide Interoperability for Microwave Access)

WiMAX available in 2 solutions:

–  fixed WiMAX (within a building…)

–  mobile WiMAX (connection of « nomad » clients)

Device maker

10 000 Wimax base station delivered by Motorola

  Annual growth rate of 40 % since the delivery of the first WiMAX access points in 2007

802.16m (WiMAX Release 2) is the next generation for this high speed mobile technology

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  Internet: extensions of Mobile IP to the IP protocol

  Wide area networks

Fixed telephony :

stable market

Cellular : growing market

Internet : Growing market

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Different aspects of mobility

  Mobile computing refers to different aspects :

  Wireless connection between a mobile terminal and an access point or between several mobile terminals

  Maintain the connection when users are on the move

  Allow handover and paging

  Identify a user whichever terminal or network he uses

  User profiles should always be recognised

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Mobile Communications

  Two aspects of mobility:

–  user mobility: users communicate (wireless) “anytime, anywhere,

  wireless LANs in historic buildings

  Personal Digital Assistant (PDA)

  The demand for mobile communication creates the need for integration of wireless networks into existing fixed networks: –  local area networks: standardization of IEEE 802.11,

ETSI (HIPERLAN)

–  Internet: Mobile IP extension of the internet protocol IP

–  wide area networks: e.g., internetworking of GSM and ISDN

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Applications

  Vehicles

–  transmission of news, road conditions, weather, music via DAB

–  personal communication using GSM

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Typical application: road traffic

UMTS, WLAN, GSM, Wimax

Personal Travel Assistant, DAB, PDA, laptop,

GSM, UMTS, WLAN, Bluetooth,

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Applications

  Traveling salesmen

–  direct access to customer files stored in a central location

–  consistent databases for all agents

–  mobile office

  Replacement of fixed networks

–  remote sensors, e.g., weather, earth activities

–  flexibility for trade shows

–  LANs in historic buildings

  Entertainment, education,

–  outdoor Internet access

–  intelligent travel guide with up-to-date location dependent information

–  ad-hoc networks for multi user games

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Applications

  Location aware services

–  what services, e.g., printer, fax, phone, server etc exist in the local environment

  Follow-on services

–  automatic call-forwarding, transmission of the actual workspace to the current location

  Information services

–  „push“: e.g., current special offers in the supermarket

–  „pull“: e.g., where is the Black Forrest Cherry Cake?

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Fixed and mobile with different caracteristics

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  Limited user interfaces

–  compromise between size of fingers and portability

–  integration of character/voice recognition, abstract symbols

  Limited memory

–  limited value of mass memories with moving parts (flash-memory or ?)

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Wireless in comparison to fixed networks

  Higher loss-rates due to interference

–  emissions of, e.g., engines, lightning

  Restrictive regulations of frequencies

–  frequencies have to be coordinated, useful frequencies are almost all occupied

  Low transmission rates

–  local some Mbit/s, regional currently, e.g., 9.6kbit/s with GSM

  Higher delays, higher jitter

–  connection setup time with GSM in the second range, several hundred milliseconds for other wireless systems

  Lower security, simpler active attacking

–  radio interface accessible for everyone, base station can be simulated, thus attracting calls from mobile phones

  Always shared medium

–  secure access mechanisms important

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Early history of wireless communication

  Many people in history used light for communication

–  flags („semaphore“),

–  150 BC smoke signals for communication;

(Polybius, Greece) –  1794, optical telegraph, Claude Chappe

  Here electromagnetic waves are

of special importance:

–  1831 Faraday demonstrates electromagnetic induction

–  J Maxwell (1831-79): theory of electromagnetic Fields, wave

equations (1864)

–  H Hertz (1857-94): demonstrates

with an experiment the wave character

of electrical transmission through space (1886, in Karlsruhe, Germany, at the location of today’s University of Karlsruhe)

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  1907 Commercial transatlantic connections

–  huge base stations (30 100m high antennas)

  1915 Wireless voice transmission New York - San Francisco

  1920 Discovery of short waves by Marconi

–  reflection at the ionosphere

–  smaller sender and receiver, possible due to the invention of the vacuum tube (1906, Lee DeForest and Robert von Lieben)

  1926 Train-phone on the line Hamburg - Berlin

–  wires parallel to the railroad track

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History of wireless communication II

  1928 many TV broadcast trials (across Atlantic, color TV,

TV news)

  1933 Frequency modulation (E H Armstrong)

  1958 Analog telephony in Germany

–  analog, 160MHz, connection setup only from the mobile station, no handover, 80% coverage, in 1971: 11000 customers

–  1972: evolution : analog, 160MHz, connection setup from the fixed network too (but location of the mobile station has to be known)

  1982 Start of GSM-specification

–  goal: pan-European digital mobile phone system with roaming

  1983 Start of the American AMPS (Advanced Mobile Phone System, analog)

  1984 CT-1 standard (Europe) for cordless telephones

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–  Fully digital, 900MHz, 124 channels

–  automatic location, hand-over, cellular

–  roaming in Europe - now worldwide in more than 170 countries

–  services: data with 9.6kbit/s, FAX, voice,

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History of wireless communication IV

  1996 HiperLAN (High Performance Radio Local Area

Network) –  ETSI, standardization of type 1: 5.15 - 5.30GHz, 23.5Mbit/s

–  recommendations for type 2 and 3 (both 5GHz) and 4 (17GHz) as wireless ATM-networks (up to 155Mbit/s)

  1997 Wireless LAN - IEEE802.11

–  IEEE standard, 2.4 - 2.5GHz and infrared, 2Mbit/s

–  already many (proprietary) products available in the beginning

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History of wireless communication V

  1999 Standardization of additional wireless LANs

–  IEEE standard 802.11b, 2.4-2.5GHz, 11Mbit/s

–  Bluetooth for piconets, 2.4Ghz, <1Mbit/s

–  Decision about IMT-2000

  Several “members” of a “family”: UMTS, cdma2000, DECT, …

–  Start of WAP (Wireless Application Protocol) and i-mode

  First step towards a unified Internet/mobile communicaiton system

  Access to many services via the mobile phone

  2000 GSM with higher data rates

–  HSCSD offers up to 57,6kbit/s

–  First GPRS trials with up to 50 kbit/s (packet oriented!)

–  UMTS auctions/beauty contests

  2001 Start of 3G systems

–  Cdma2000 in Korea, UMTS in Europe, Foma (almost UMTS) in Japan

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  2001: start of WiMax (Worldwide Interoperability for

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1995/96/97: IEEE 802.11, HIPERLAN

2005?: MBS, WATM

1988:

Inmarsat-C

analog digital

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Areas of research in mobile communication

  Wireless Communication

–  transmission quality (bandwidth, error rate, delay)

–  modulation, coding, interference

–  media access, regulations

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Simple reference model used here

Application Transport Network Data Link Physical

Medium

Data Link Physical

Radio

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Influence of mobile communication to the layer model

–  service location –  new applications, multimedia –  adaptive applications

–  congestion and flow control –  quality of service

–  addressing, routing, device location

–  hand-over –  authentication –  media access –  multiplexing –  media access control –  encryption

–  modulation –  interference –  attenuation –  frequency

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Systèmes sans fil

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Wireless & mobile Internet

–  Ongoing research

  Wireless communications

  transmission quality (bandwidth, error rate, delay)

  Modulation, coding, interferences

  Access support, regulation, …

–  Mobility

  Services dependant on the localisation

  QoS support (delay, jitter, security),…

–  Portability

  Energy consumption

  Limited processing power, …

  Usages

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Reference model for the course

Medium

Data Link Physical

Radio

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Reference Model for this course

  Influence of mobile communications on the

hierarchical OSI model

–  Application Layer : localisation services, adaptive applications

–  Transport Layer : Flow control and congestion control

–  Network Layer : addressing, locating, routing, handover, Quality of Service

–  Data Link Layer: authenthication, medium access, multiplexaging

–  Physical Layer : encryption, modulation, interference, loss, frequencies

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  frequencies & regulations

  signals, antennas, signal propagation

  multiplexing, modulation, spread spectrum, cellular system

–  Media Access

  motivation, SDMA, FDMA, TDMA (fixed, Aloha, CSMA, DAMA, PRMA, MACA, collision avoidance, polling), CDMA

–  Wireless LANs

  Basic Technology

  IEEE 802.11a/b/g, 15, Bluetooth

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