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Discover how NICTA and NCTU are revolutionizing transportation with wireless networks. Learn about the various ITS systems and their benefits, from safety to efficiency and environmental impact. Explore the market trends and potential growth in the ITS industry. Find out about the STaR project and SCATS, an adaptive traffic control system used in Sydney.
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Smart Road:Wireless Networks for Intelligent Transport system Kun-chan LanNICTA NCTU
About me • Graduated from USC in 2004 • Currently working as a researcher at National ICT Australia (NICTA) • Past research • Internet measurements, traffic modeling and simulations • Current research • Wireless mesh networks and vehicular ad-hoc networks NCTU
About NICTA • A national research institute funded by Australia Government • Our research staff includes regular full-time researchers and contributed staff from major universities such as Australian National Univ., Univ. of Sydney, Univ. of Melbourn, New South Wales of Univ. etc • Our focus • Research, commercialization, education, collaboration NCTU
About NICTA • A number of research labs • located in Sydney, Canberra and Melbourn • A variety of research programs • Empirical Software Engineering; • Interfaces, Machines, And Graphic ENvironments • Networks and Pervasive Computing. • Embedded, Real-Time, and Operating Systems • Formal Methods • Symbolic Machine Learning and Knowledge Acquisition • Statistical Machine Learning; • Systems Engineering and Complex Systems • Wireless Signal Processing • Logic and Computation; • Autonomous Systems and Sensing Technologies • Statistical Machine Learning. • Sensor Networks; • Network Information Processing. NCTU
What is Intelligent Transportation System (ITS) ? • Computer and communication technologies applied to management of transportation systems • To manage it in a safe and efficient manner • To monitor traffic conditions (accident, incidents, construction work, weather, major events) • Control traffic flow • To provide information to the traveling public about traffic conditions NCTU
Why ITS? • Improved safety to drivers • e.g. reduce accident • Improved traffic efficiency • e.g. reduced traffic congestion • Improved environmental quality • e.g. reduced fuel/exhaust • Improved economic productivity • e.g. broadband service on buses NCTU
Improve safety • highway deaths > 40K in 2003 for US alone • Studies showed the use of ramp meters reduce accidents 15-50%. • In-vehicle computer visioning cameras • warn operators of drowsy driving behavior. • Results showed the system improved safety and decreased fuel consumption 15%. • Radar sensors on trucks • warn operators of obstacles in blind spots • at-fault accidents decreased 34% in 1 year. NCTU
Improve efficiency • in-vehicle navigation systems • a travel time savings of more than 10% • intelligent cruise control vehicles (ICC) • use road sensor data to optimize vehicle speeds and match signal timing • increase link capacity 3-6%. NCTU
Improve environmental quality • E-Zpass (an electronic toll collection) in NJ • saves: 1.2 mil gallons of fuel/yr, 0.35 tons of CO/day, and 0.056 tons NOx/day. • Similar study from Baltimore • reduced hydrocarbons and Carbon monoxide emissions by 40-63%, and reduced emissions of Nitrogen oxides by approximately 16%. NCTU
ITS market • Promising market • US market for ITS is estimated to grow from $5 billion to $35 billion by 2010. • $700 billion is expected to be spent on transport infrastructure in the Asia Pacific market • In 2005, The Minister for ICT in Australia launched a new industry cluster in Victoria for the ITS market • the HK Government proposed to spend US$423 million on ITS in the next decade • In Japan, the annual market size has been estimated at 4 billion ECU by 2010. • The European standardized GSM-R • cellular solutions in the transportation sector • $5 billion new market in Europe within five years NCTU
Today’s talk • Part 1 • A brief talk about a project (STaR) we recently started at NICTA • A wireless mesh network for ITS • Not much results at this point, only architecture overview for today • Part 2 • two vehicular-network applications • MOBNET – A NEMO-based Network Mobility Testbed • MOVE – A Mobility mOdel generator for VANET • Only overview talk today, no discussion on math or protocol NCTU
About STaR (Smart Transports and Roads) • A multi-million research project we recently started at NICTA • Only a few months old • Collaborating with New South Wales Road and Traffic Authority (NSW RTA) • NSW RTA is the creator of SCATS, a real-time traffic management system • SCATS is used in Sydney and ~80 other cities around the world • It is expected that some outcome of STaR project can be integrated into SCATS in the future NCTU
SCATS (The Sydney Coordinated Adaptive Traffic System)) • An adaptive traffic control system • Goal • Minimize vehicle travel time when traffic is light • Maximize road capacities when traffic is heavy • Components of SCAT • Subsystem: 1-10 intersections • Local controller: one at each intersection • Critical intersection: need accurate timing control • Non-critical intersections synchronize with the critical intersection • Regional computer: control up to 64 subsystem Regional computer subsystem subsystem subsystem NCTU
SCATS (The Sydney Coordinated Adaptive Traffic System)) • Local controller: optimize local traffic flows • On a phase-by-phase basis • Phase length: time from one green to next green • Regional computer: optimize subsystem capacity • On a cycle-by-cycle basis • One cycle contain multiple phases: typically 40s-150s • All intersections in the same subsystem has the same cycle Regional computer subsystem NCTU
Goal of STaR • Improved traffic flow • Improved public safety • Improved performance, efficiency and running cost for public transports • Improved SCATS revenue in the multi-billion dollar ITS market NCTU
Benefit from working with RTA • Access to real-time and historical road traffic data • Access to public infrastructure (traffic controller,video camera, road-side sensors, etc) • Access to other RTA systems NCTU
Problems with the existing RTA network • Rely on a fixed communication infrastructure (ISDN and dial-up) • Costly to install, operate and maintain • Easy to be damaged • Low bandwidth (< 32KB/s): inflexible in its application NCTU
Wireless mesh networks for ITS • Replacement of current system is highly sought after • By RTA and other traffic authorities elsewhere • But commercial off-the-shelf systems (e.g. DSL, GPRS) don’t provide required reliability and timeliness, and still incur costs • NICTA proposes a multiple-hop wireless mesh network to replace the dial-up network • Easy deployment • Infrastructureless: lower maintenance cost • Initially, a 16-node testbed in Sydney CBD (Central Business District) area NCTU
Requirement for the test-bed • Representative locations • Foliages/trees • Pedestrians • Passing traffic • High-rise buildings • Easy access • Close to NICTA • Cover at least one critical intersection • Multiple paths available for each source/destination pairs • can provide external source of power to mesh router NCTU
Why wireless mesh networks? • Wireless mesh networking is a promising technology to replace current system • ease and speed of installation, without reliance on a telecommunications carrier or dependence on their time frames; • lower on-going costs than the current system, with no annual or monthly rental or service fees; • flexibility to connect new locations, for new intersections or during road works or emergencies; • Others also recognise that the potentials of wireless meshes NCTU
Commercial product • Meshnetworks Inc (now acquired by Motorola) • Tropos Networks • LocustWorld (MeshAP) • Intel • Nortel • Microsoft • Kiyon • Radiant Networks (Cambridge-based, work with BT) • Invisible Networks • Green Packet Inc. (M-Tapei) • SeattleWireless, NYCWireless,… • many others.. NCTU
Test-beds In academia • MIT (Roofnet project) • Rice university (TFA project) • Berkeley (DGP project @ India) • Trinity College @ Dublin (WAND project) • University of Massachusetts @ Ahmerst (Diesel Net) • UC Santa Barbara • UC San Diego • State University of New York @ Stony Brook • UCLA • others… NCTU
STaR network topology public transport Regional computer Traffic controller Mesh box camera road-side sensor Internet NCTU
Test-beds @ NICTA • We are currently building two test-beds at NICTA • Indoor – Linksys WRT54GS • ~$100 • Linux-based firmware • OpenWRT support • For research above transport layer • Outdoor – Soekris boards • ~$300 • Use Compact Flash card for OS • Customized MAC • Can use any type of radio • We’re only interested in research Issues above MAC NCTU
Current testbed activities • Wireless survey • Building mesh routers with soekris boards • Integrate mesh routers with SCATS simulator • Integrate mesh routers with real SCATS traffic controller • Network management NCTU
Wireless survey • Understand the radio property in real word • What to measure • Signal strength quality • Throughput • Packet losses • MAC layer re-transmission • as a function of • Distance • Transmission rate • Type/height of antenna • Number of MAC RETRY • Two phases • Open-space measurements • Intersection measurements NCTU
Multi-radio mesh router • Soekris net4521 • 133 Mhz AMD • 64 Mbyte SDRAM • Use CF card for OS (pebble linux) • 2 Ethernet ports • 1 Serial port, DB9. • 1 Mini-PCI slot • 2 PC-Card slot for wireless adapters • Board size 9.2" x 5.7" • External power supply 11-56V DC • Operating temperature 0-60 °C NCTU
Integrating with traffic simulator • Test mesh router on the traffic simulator before integrating with real traffic controller • A micro-traffic simulator Paramics is used, located at UNSW • One high speed link between UNSW and NICTA that allows the mesh router to talk to the Paramics simulator remotely NCTU
Integrating with SCATS traffic controllers • SCATS system • A large number of kerbside controllers that control traffic signal • A set of regional controllers that control kerbside controllers • Star topology (Masterlink mode) • Currently connected by leased lines via a Bell 103 modem at 300 baud • Some kerbside controllers have a special role for synchronizing signal timing when the regional controller is down (Flexilink mode) • Each kerbside controller has a 25-pin RS-232 connector for external access kerbside controller regional controller critical intersection NCTU
Network management • Graphic interface that shows • Wireless connectivity • Network topology • Link latency • Link throughput • Routing path • Router status NCTU
practical Issues for street deployment • Waterproof/weatherproof • Power source • Antenna placement • Vandalism • Passing traffic NCTU
Research Challenge • Scalability • Connecting numerous road-side devices to SCATS • Need to Integrate video cameras: High throughput, low jitter • Reliability • Mission-critical data (e.g. accident detection, traffic signal control, etc) • Requires timely routing that is robust against faults in nodes or links • Low latency • SCATS is a real-time traffic control system (< 1 sec) • Heterogeneity • Requires support for different radio types • e.g. incrementally deploy new radio technologies NCTU
Research focuses • New multi-radio multi-channel MAC • Scalability/reliability/latency • Multi-path routing • Reliability/latency • Fault detection and recovery • Reliability • Network management • Very difficult to physically to access the mesh nodes once they are deployed • Need to mechanism to node diagnostics, software upgrade, etc • Communication between vehicles and road-side devices NCTU
Current status of STaR • 4 months old, not much technical results yet • 6 months to deliver a pilot testbed that controls real traffic light • 14 researchers/students working on this project • International research collaboration(U. Cal @ Davis and U. Texas @ Arlington) • Communication with Australian startups • We’ve developed a couple of applications for ‘vehicle to road-side’ component though • MOBNET • Network mobility testbed (LANMAN 2005) • MOVE • Mobility model generator (poster in MOBICOM 2005) NCTU
Today’s talk • Part 1 • A brief talk about a project (STaR) we recently started at NICTA • Part 2 • two vehicular-network applications • MOBNET – A NEMO-based Network Mobility Testbed • MOVE – A Mobility model generator for VANET NCTU
Mobile Network • Providing broadband service for public transport passengers is becoming a popular ITS service • E.g. Connexion by Boeing • Mobile Network (MN):a network that can move and attach arbitrary points in the Internet • Mobile Network • On-board LAN • Mobile Router: • manage movement of MN and provide Internet access to MNNs • Mobile Network Node (MMN) • MMN: a node in the MN • Local Fixed Node (LFN) • Visiting Mobile Node (VMN) • Standardized protocol: NEMO • Extension of MIPv6 NCTU
MOBNET - Network mobility testbed • Ways to conduct network research • Simulation • Emulation • Real implementation • Physical layer models in wireless simulations are typically over-simplified • Need realistic testbed • Existing wireless testbed • CMU (ad-hoc routing) • TAP, Roofnet (mesh network) • ORBIT (generic testbed) • Existing work does not support testing of network mobility protocols • Our contribution: a testbed for network mobility research MOBNET: The Design and Implementation of a Network Mobility Testbed", Kun-chan Lan, Eranga Perera, Henrik Petander, Christoph Dwertmann, Lavy Libman, Mahbub Hassan, IEEE LANMAN 05’ NCTU
Mobile Nework testbed functionality • Emulation of a mobile network • Experimental control • Topology control • Mobility control • Management of the testbed NCTU
Emulation of a Mobile Network • A NEMO-based mobile router • Extended from HUT MIPv6 • Built on Linux 2.4.26 • Support NEMO implicit mode • Can use link layer information to trigger handoff • Support Route Optimization • Extension of MIPv6 RO NCTU
Experimental control • Topology control • NIS NET network emulator • Mobility control • Mobility emulator (MobE) • Emulate the movement of MR • Emulate the variations of radio propagation by changing the transmission power of the AP • Can be driven used pre-made mobility patterns • Markov Chains model • For controllable experiments • Signal strength traces NCTU
Mobility emulator • Architecture • Input parser • Graphical interface • AP power level controller • AP power level control • web interface • telnet • Modeling signal strength variations • Discrete markov chain • e.g. frequency of changing from one power level to another, etc. NCTU
MR moving from ap1 toward ap2 Mobility Emulator interface NCTU
Testbed management • We’d like to make our testbed available to other researchers in the future • Remote management server • Remote users access • Testbed monitoring • Testbed maintenance NCTU
Node generator - Virtual MMNs • Currently each node is implemented via one single machine • Not scalable: how to emulate a large number of MMNs • Implement each MMN as a single process • Virtual interface: a single wireless interface is abstracted into multiple virtual interfaces • Each MMN connects to MR via a virtual interface NCTU
Effect of NEMO handoff on TCP and UDP • Experiment setup • 1 home network and 2 foreign networks • Traffic is sent from CN to MNN • Using Iperf to generate TCP and UDP traffic • UDP: 200Bytes at 100Kbits/s • Packet of a smaller size is more sensitive to the effect of handoff latency NCTU
Effect of NEMO handoff on TCP and UDP Use measurements on the Home network as a base line NCTU