1 Growth in traffic in different access system Growth in traffic in - - PDF document

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無線網路多媒體系統 Wireless Multimedia System

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

• Dr. Eric Hsiaokuag Wu

hsiao@csie.ncu.edu.tw

http://wmlab.csie.ncu.edu.tw/course/wms 2009 Fall

First Week Agenda First Week Agenda

 Course Preview  Wireless Multimedia/Mobile Computing / Pervasive Computing  Wireless Mobile Communications  System Review and Fundamental Problems  Next Week

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Course Contents Course Contents

 Fundamental Wireless Technology

• Propagation Model
• Wireless Medium Access
• Transport Solutions
• Ad hoc/Mesh Wireless System
• Cellular System

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

• Middleware Systems
• Multimedia System

 Advanced Wireless Technology

• Multicasting
• Beyond 3G
• Routing Algorithms/Mesh Network/VANET
• QoS/ Reliable Mutimedia Transmissions

1000 1200 1400 1600 1800

ers (10K)

台灣行動電話發展趨勢圖 台灣行動電話發展趨勢圖

A t l Fi A t l Fi

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory 200 400 600 800 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 Subscribe

Predicted in 1997 Actual Figure Actual Figure

Roaming Across a variety of heterogeneous network and

service environments Application

RTP, TCP, UDP RSVP IP, Mobile IP

OS, MiddleWare

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Wireless Network Layer Clustering(optional) Data Link MAC Radio

WiMAX Nomadic and Portable WiMAX Nomadic and Portable

Non Line of Sight Non Line of Sight Point to Multi Point to Multi-

• point

point

802.16 802.16 802.16 802.16

Line of Sight Line of Sight BACKHAUL BACKHAUL

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

INTERNET INTERNET BACKBONE BACKBONE Telco Core Telco Core Network or Network or Private (Fiber) Private (Fiber) Network Network

SEEKS BEST SEEKS BEST CONNECTION CONNECTION

Laptop Connected Through 802.16 2 to 3 Kilometers Away

802.16e PC 802.16e PC Card Card Ref: Margaret LaBrecque , “Enabling Deployments through Standards and Certification,” WiMax, 2003

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2

WiMAX 802.16 WiMAX 802.16

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

0.855 1.289 1.704 2.395 3.339 4.549 4.076 3.438 1 2 3 4 5 B P S K _ 1 _ 2 B P S K 3 / 4 Q P S K 1 / 2 Q P S K 3 / 4 Q A M 1 6 1 / 2 Q A M 1 6 3 / 4 Q A M 6 4 2 / 3 Q A M 6 4 3 / 4 M bps

Growth in traffic in different access system Growth in traffic in different access system and voice and data services and voice and data services

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Forecast number of subscribers Forecast number of subscribers

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Frequency Hopping Spread Spectrum Frequency Hopping Spread Spectrum  Transmitted signal is spread over a

wide range of frequencies. (i.e. 2.400-

2.485 GHz)

 Transmission usually hop 35 times

per second.

f6 f7 Freq. Freq.

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Time Time f3 f2 f1 f4 f5

Direct Sequence Spread Spectrum Direct Sequence Spread Spectrum

To transmit a 0 the station use a unique To transmit a 0 the station use a unique “chip chip sequence sequence”: To transmit a 1 the station use the one To transmit a 1 the station use the one’ ’s complement s complement

• f its chip sequence:
• f its chip sequence:

1 0 1 1 0 1 0 1 1 0

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

p q p q Therefore if data is 1010 it will transmit: Therefore if data is 1010 it will transmit: 0 1 0 0 1 0 1 0 0 1 1 1

Narrowband vs. Wideband Narrowband vs. Wideband

1 1 1 1 1 1 1 1

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory Bandwidth Bandwidth energy Bandwidth energy

Spread Spread

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Ultra Ultra-

• Wideband Radio

Wideband Radio

Camcorder DVD

TV Home Gateway Monitor

Bluetooth,

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

1.6 1.9 2.4

Bluetooth, 802.11b Cordless Phones Microwave Ovens

GPS PCS 5

802.11a

• 41 dBm/Mhz

“Part 15 Limit”

UWB Spectrum

Frequency (Ghz) Emitted Signal Power

10.6 3.1

CR (Cognitive Radio) CR (Cognitive Radio)

 The CR idea was initially introduced by Joseph Mitola. On average, only

2% of allocated spectrum in the U.S. is actually in use

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Multi Multi-

• channel, Multi

channel, Multi-

• Radio, MIMO

Radio, MIMO

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Wireless Mesh Network. Wireless Mesh Network.

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mesh Network Scenario Mesh Network Scenario

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Aeronautical Communications Aeronautical Communications

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Wireless Applications Scenario Wireless Applications Scenario

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Multimedia over IP Multimedia over IP

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3GPP 3GPP -

• Release 5 IMS & HSDPA

Release 5 IMS & HSDPA

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

IMS Service Scenario IMS Service Scenario

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Context Aware Communication Context Aware Communication

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Business Finder Business Finder

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

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Adaptive Applications Adaptive Applications

Video Audio Text Graph Varied type

• f service

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Adaptive application coding

Quality

High Low

Situation Situation-

• Aware Wireless Networks

Aware Wireless Networks

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Network Mobility Management Network Mobility Management

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Femtocell

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

異質無線多網多媒體分享與推薦平台場景圖

metadata 1 metadata 2 metadata n

搜尋 推薦 傳送 WiFi

Alice

….

人際網路

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Internet Bluetooth WiMax 搜尋 推薦 傳送

人際網路 Bob

IEEE 802.11 WLAN IEEE 802.11 WLAN

Ad hoc mode Infrastructu re mode

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

RTS CTS Ack Data NAV Next MPDU

Src Dest Other

CW

Defer Access Backoff after Defer NAV

(RTS) (CTS) DIFS SIFS SIFS SIFS

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Quiz 0: WLAN Performance Anomaly Problem Quiz 0: WLAN Performance Anomaly Problem

802 11b 1 Mbps data rate

A

Mesh Node

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory nominal rate (Mbps) throughput (Mbps) A B A B 11 11 3.09 3.36 B

802.11b 11 Mbps data rate

1 11 0.73 0.76

Fairness for upstream and downstream Fairness for upstream and downstream

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Expectation of the Class Expectation of the Class

 Basic Understanding of PCS world  Being able to do the wireless research  Developing the capability to invent the key wireless applications

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Course Process Course Process

 Paper reading and your presentations  Wireless Multimedia Applications Exercises

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mobile Computing Mobile Computing

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mobile phone today = multipurpose terminal for ...

Information Client Internet Browser

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

E-mail Client Authentication Device E-purse Share dealing, etc.

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Reading list for This Lecture Reading list for This Lecture

Required Reading:

(S.2001) M. Satyanaraynan, “Pervasive Computing: Vision and Challenges”, IEEE Personal Communication Magazine, (August 2001), pp.10-17 (Bi2001) Qi Bi, George I. Zysman, and Hank Menkes, “Wireless Mobile Communications at the Start of the 21

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Century”, IEEE Communication Magazine (January 2001), pp. 110-116

Further Reading

(Bolcskei2001) H. Bolcskei, A. J. Paulrai, K. V. S. Hari, and R. U. Nabar, “Fixed Broadband Wireless Access: State of the Art, Challegnes, and Future Directions”, IEEE Communication Magazine

Mobile Computing Mobile Computing

Mobile Operating Systems Verticals Horizontals Operating Systems Applications

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

WANs LANs Notebooks PDAs Phones PIM Wireless Networks Devices p g y

Mobile Computing Mobile Computing

 information processing in general

• not just communication or just computing, but both

 Any medium or combination of medium

• process not just telephone voice or just data, but multimedia

 Mobility

• components of the systems may be

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory



moving, tether-less (wireless), portable

• uses of the system may be moving

Why should we care ? Why should we care ?

 Reason # 1 : $$$ & jobs  Explosive growth of wireless voice, paging, and data services

• 35-60 percent annual growth in the past decade
• mobile phones in US will be 42 % of fixed -line phones by 2000
• 700 million mobile users at the end of 2000
• One billion expected by 2003

 Big demand for portable communicators and computers

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

 Big demand for portable communicators and computers

• 2 M portable computer in 1988 to 74.1 M units in 1998

Is there a more “academic” reason ? Is there a more “academic” reason ?

 Reason # 2: a next step in the evolution of information system  Evolution from personal computing to networked computing to mobile

computing

 Evolution from wired telephony to cordless telephony to mobile

cellular telephony

 At the same time unification of computing and communication

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

At the same time, unification of computing and communication

Mobile Multimedia Systems Mobile Multimedia Systems

 Ubiquitous information access (everybody else)

• e.g. wireless computing, mobile computing, nomadic computing
• information distributed everywhere by “the net”
• users carry (wireless) terminals to access the information services
• terminal is the universal service access device
• terminals adapt to location and services

K l d b d i t

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

• Knowledge-based society

 Flexible Users Choices

• In terms of access, service, content
• Any where, anytime, any terminal equipments

 Wearable Computing terminal / Mobile Broadband services

(MBS)

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Pervasive Computing Pervasive Computing

 Technology that disappears

• The most profound technologies are those that disappear. They weave

themselves into the fabric of everyday life until they are indistinguishable from it”.

 Ubiquitous (Invisible) Computing (Xerox PARC)

• Cheap computers of different scale and types embedded everywhere
• Potentially 100s of computers per room that disappear into background

( ti b d t b d li b d )

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

(e.g. active badge, tabs, pads, live boards..)

• User centric, not terminal centric
• Computers swapped and shared among users

 Effective Use of Smart Spaces  Invisibility  Localized Scalability  Masking Uneven Conditioning

Support for Pervasive Computing Support for Pervasive Computing

 User Intent  Cyber Foraging  Adaptation Strategy  High-Level Energy Management  Balancing Pro-activity and Transparency

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

 Privacy and Trust  Impact on Layering

Pervasive Computing Pervasive Computing

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Aura Client Aura Client

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Wireless Communications Wireless Communications

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mobile Communications Fixed Broadband Wireless Communications

Evolution of Mobile Wireless Systems Evolution of Mobile Wireless Systems

 First Generation : Analog – Voice

• Analog modulation
• Cellular phone (AMPS) with manual roaming
• Cordless phones
• Packet radio networks

 Second Generation : Digital - Voice & Data

• WAP (wireless application protocol)

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

( pp p )

• 2.5 G GPRS
• Wireless data LANs (802.11), MANs (Metricom), WANs (CDPD, ARDIS, RAM)

 Third Generation: Digital – Multimedia

• Unified digital wireless access anytime, anywhere
• Voice, data, images, video, music, sensor etc.

 4G~ Life after Third-Generation Mobile Communications

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Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Wireless Personal Communications Wireless Personal Communications

 What is it?

• Cellular telephone
• Cordless telephone
• Paging systems
• Wide area data networks
• Local area data networks

 Many ways to segment PCS

A li ti Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

• Applications
• Extent of coverage
• Degree of mobility (speed, area)
• Circuit switched voice vs. packet-switched data
• Mode of communication (messaging, two-way real time, paging, agents)
• User location (indoor vs. outdoor, train, airplane)

 Common ingredients in all PCS activity

• Desire for mobility in communications
• Desire to be free from tethers

2000 Market Share 2000 Market Share

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Mobile Terminal Growth Mobile Terminal Growth

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GPRS Architecture

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

RS Spectrum Allocation RS Spectrum Allocation

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

GSM 1800

IMT-2000

FDD

MSS

TDD I J G H I J K L

MSS

2110 2170

IMT 2000

2200 2025 2010 1980 1985 1975 1920 1915 1905 1900 1895 1880 1850 1805

MHz

G : Reserved I : PACS K : PHS H : DECT J : PACS (To Be Licensed) L : Reserved

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Wireless Mobile Interface Wireless Mobile Interface

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Elements of UMTS Architecture Elements of UMTS Architecture

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

第三代行動電話之技術標準 第三代行動電話之技術標準

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Location Location-

• Based Applications

Based Applications

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

3G G-

• Network integration

Network integration

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

3GPP 3GPP-

• Release 5

Release 5 IMS & HSDPA IMS & HSDPA

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

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Mobile Broadband System Mobile Broadband System

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mobile System Evolution Mobile System Evolution

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

WiMAX Nomadic and Portable WiMAX Nomadic and Portable

Non Line of Sight Non Line of Sight Point to Multi Point to Multi-

• point

point

802.16 802.16 802.16 802.16

Line of Sight Line of Sight BACKHAUL BACKHAUL

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

INTERNET INTERNET BACKBONE BACKBONE Telco Core Telco Core Network or Network or Private (Fiber) Private (Fiber) Network Network

SEEKS BEST SEEKS BEST CONNECTION CONNECTION

Laptop Connected Through 802.16 2 to 3 Kilometers Away

802.16e PC 802.16e PC Card Card Ref: Margaret LaBrecque , “Enabling Deployments through Standards and Certification,” WiMax, 2003

19

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

National Central University National Central University & Hughes Network Systems Hughes Network Systems LMDS Demo Briefing LMDS Demo Briefing

November 1999

Campus Network Campus Network

ATM

E t h e r S w i t c h E t h e r S w i t c h

Campus Network

WWW Server OC3 interface

Figure 1: Wireless Network Infrastructure

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

A c c e s s P o i n t A c c e s s P o i n t A c c e s s P o i n t A c c e s s P o i n t E t h e r n e t

WWW Server

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LMDS NCU Test LMDS NCU Test-

• bench

bench

REMOTE

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

G-17635P 7/28/99 HUB HUB CENTRAL OFFICE PSTN INTERNET ADD-DROP MUX

BACKBONE SYSTEM

CLASS V SWITCH DATA SWITCH

Architecture of the Demo Architecture of the Demo

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

National Central University Demo National Central University Demo Layout Layout

EMS RT#1 RT#2

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

G-17833P 8/19/99 VIDEO DATA (INTERNET) VOICE DS3 MUX 38 GHz RADIO HUB HT#1

Step.1 LMDS Architecture Step.1 LMDS Architecture

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

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WiMAX Consumer Last Mile WiMAX Consumer Last Mile

Non Line of Sight Point to Multi-point

OUTDOOR CPE

802.11 802.11

Point to Point BACKHAUL

xDSL

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

INTERNET BACKBONE Telco Core Network or Private (Fiber) Network

INDOOR CPE

802.11 802.11 and and 802.16 802.16

Ref: Margaret LaBrecque , “Enabling Deployments through Standards and Certification,” WiMax, 2003

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IEEE 802.11 Configurations IEEE 802.11 Configurations -

• Independent

Independent

 Independent

• one Basic Service Set - BSS

Ad H t k

AH3 Station Station AH1 AH2

Ad Hoc Network Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

• Ad Hoc network
• direct communication
• limited coverage area

13

Topology of a Wireless LAN Topology of a Wireless LAN

 進接(Access)應用: 使用者與網路的連接  中繼(Trunk)或骨幹(Backbone)應用: 網路與網路之間的連接. 例如,大樓與大樓之間的通

訊 或是遠方網路的連接

AP

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory 訊, 或是遠方網路的連接.

Wireless Bridge

1~10公里

Wireless Bridge

RTS CTS Ack Data NAV Next MPDU

Src Dest Other

CW

Defer Access Backoff after Defer NAV

(RTS) (CTS) DIFS SIFS SIFS SIFS

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

• Duration

Duration field in RTS and CTS frames distribute field in RTS and CTS frames distribute Medium Medium Reservation Reservation information which is stored in a information which is stored in a Network Network Allocation Vector (NAV) Allocation Vector (NAV). .

• Defer on either NAV or "CCA" indicating

Defer on either NAV or "CCA" indicating Medium Busy Medium Busy.

• Use of RTS / CTS is optional but

Use of RTS / CTS is optional but must must be implemented. be implemented.

Node Contention & Rate Adaptation Node Contention & Rate Adaptation

without RTS/CTS

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

[Choi, ACM SIGMETRICS’05]

IP integration IP integration

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

WiMedia Solutions WiMedia Solutions – – Simple Usage Simple Usage

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Capacity and Mobility Capacity and Mobility

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地球村的建立 地球村的建立

衛星本體

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

衛星本體 衛星本體

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

衛星本體

衛星本體 衛星本體 衛星本體 衛星本體 衛星本體 衛星本體 衛星本體

Sky of Satellites Sky of Satellites

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory 衛星本體 衛星本體 衛星本體 衛星本體 衛星本體 台北陽明山 網路控管中心 中壢 國立中央大學 研究二館

DirecPC Satellite Experiments DirecPC Satellite Experiments

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Cellular System

Ubiquitous Access

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

WLAN WLAN

DirecPC

“Anytime Anywhere ” Information Anytime Anywhere ” Information System System

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

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Fundamental Issues Fundamental Issues

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Three System Components Three System Components

End-Point Terminal Architecture Infrastructure Network architecture

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Services OS & Middleware

Personal area network Personal area network

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Connect devices to internet on the Connect devices to internet on the mobile mobile infrastructure world wide infrastructure world wide

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mobility Unpredictable channel Adaptive Algorithm

QoS and Multimedia Traffic Support

Application

RTP, TCP, UDP RSVP IP, Mobile IP

OS, MiddleWare

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

channel by QoS Information by QoS Requirement

Wireless Network Layer Clustering(optional) Data Link MAC Radio

Mobility Unpredictable channel Adaptive Algorithm

QoS and Multimedia Traffic Support

Application

RTP, TCP, UDP RSVP IP, Mobile IP

OS, MiddleWare

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

channel by QoS Information by QoS Requirement

Wireless Network Layer Clustering(optional) Data Link MAC Radio

16

Channel Propagation and Fading Channel Propagation and Fading

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Intra Intra-

• Domain Handoff

Domain Handoff

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Resource Sharing Resource Sharing

 Reservation Approaches

• Centralized Control
• token (round robin)

 Collision Approaches

• fight for resource
• distributed control

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Through A Centralized Control Through A Centralized Control

 TDMA, FDMA, CDMA

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

MACA/PR MACA/PR

Cycle RTS CTS Pkt Res Pkt R

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

S D Pkt (t1) Pkt (t2) Pkt (t3) Pkt (t1) Res (t2) Res (t2) Res (t2) Res (t2) Res

Mobility Unpredictable channel Adaptive Algorithm

QoS and Multimedia Traffic Support

Application

RTP, TCP, UDP RSVP IP, Mobile IP

OS, MiddleWare

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

channel by QoS Information by QoS Requirement

Wireless Network Layer Clustering(optional) Data Link MAC Radio

17

Mobility Unpredictable channel Adaptive Algorithm

QoS and Multimedia Traffic Support

Application

RTP, TCP, UDP RSVP IP, Mobile IP

OS, MiddleWare

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

channel by QoS Information by QoS Requirement

Wireless Network Layer Clustering(optional) Data Link MAC Radio

Internetworking, IP, Mobile Internetworking, IP, Mobile

 Internetworking

• roaming through different networks
• supporting IP format
• supporting IP portability

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Mobility Unpredictable channel Adaptive Algorithm

QoS and Multimedia Traffic Support

Application

RTP, TCP, UDP RSVP IP, Mobile IP

OS, MiddleWare

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

channel by QoS Information by QoS Requirement

Wireless Network Layer Clustering(optional) Data Link MAC Radio

What problem does Multimedia Bring? What problem does Multimedia Bring?

Telephone Circuit network

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

5

Integrated Service Packet Network Emerging technologies:

• 1. “Datagrams” + “Flows” IPv6
• 2. “Virtual Circuits” (ATM)

System Configurations System Configurations

 Ad hoc ~ Multi-hop

• Wireless LAN
• Blue-tooth
• Packet Radio
• WAMIS

 Cellular ~ GSM, WAP, GPRS, 3G

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

, , ,

 Satellite ~ LEO, GEO

Ad Hoc Wireless Network

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

18

Wired Network, Internet, PSTN, ATM network

Access Point Gateway

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Wired Network, Internet, PSTN, ATM network

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

User Moves Handover

Typical Cellular Call Typical Cellular Call

 Initialization (find your base-station)  Service Request

• Location Level : Paging
• Channel Assignments

 Handoff

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Wireless Comm: Wireless Comm: Heterogeneity & Security Heterogeneity & Security

 Heterogeneous networks Internet 中央大學 臺灣大學

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

臺灣大學 Taipei Cellular Horizontal Handoff Vertical Handoff

Limited & Variable Bandwidth Limited & Variable Bandwidth

 Low bandwidth compared to wired  Highly variable bandwidth  High latency

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Wireless Communication Wireless Communication

 More difficult than wired communication  Dis-connections

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19

Mobility Mobility

 Address migration  Location-dependent information  Migration locality

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Portability Portability

 Light weight power  Risks to data  Small user interface  Small storage capacity

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Challenges in Mobile Multimedia Infor Challenges in Mobile Multimedia Infor-

• System

System

 Portable end-points  End-to-end Quality of Services  Seamless operation under context (location) changes  Context-aware operation  Secure operation

Wireless & Multimedia Network Laboratory Wireless & Multimedia Network Laboratory

Channel Propagation and Fading Channel Propagation and Fading

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