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Talk outline

A New Ph.D. Program in Computational Transportation Science Ouri Wolfson University of Illinois, Chicago. Talk outline. cytuc. Computational Transportation Science. Mobi-dik. Data Dissemination. Background for Computational Transportation Science.

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Talk outline

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  1. A New Ph.D. Program in Computational Transportation ScienceOuri WolfsonUniversity of Illinois, Chicago

  2. Talk outline cytuc Computational Transportation Science Mobi-dik Data Dissemination

  3. Background for Computational Transportation Science • Problem: Real-time information to traveler has not changed much in 40 years • Objective: Enable dramatic improvement of the travel experience – based on information • Idea: Capitalize on the wireless personal communication tidal wave to revolutionize transportation • Approach: Architecture and software platform for the development of novel transportation applications

  4. Transportation New Ph.D. program Information Technology • Funded by the National Science Foundation, $3M. • UIC match: $2.5M • Will train about 30 Scientists • Researchers from 12 academic departments, 6 colleges

  5. Main differences from other transportation centers • Focus on: • Computer Science and IT • Traveler rather than vehicular technology • Applications above communication layer • Education component

  6. Wireless P2P data management cytuc Computational Transportation Science Mobi-dik Data Dissemination

  7. Mobile Local Search: applications • social networking (wearable website) • Personal profile of interest at a convention • Singles matchmaking • Games • Reminder • Messaging (SMS) • mobile electronic commerce • Sale on an item of interest at mall • Music-file exchange • transportation • Announce sudden stop, malfunctioning brake light • Announce patch of ice discovered by abs • Search close-by taxi customer, parking slot, ride-share • emergency response • Search for victims in a rubble • asset management and tracking • Sensors on containers exchange security information => remote checkpoints • mobile collaborative work • tourist and location-based-services • Closest ATM

  8. resource 8 resource-query C resource-query A resource 1 resource 2 resource 3 resource-query B resource 4 resource 5 Environment Pda’s, cell-phones, sensors, hotspots, vehicles, with wireless capabilities A central server does not necessarily exist Local query Local database Resources of interest in a limited geographic area possibly for short time duration Applications coexist

  9. 802.11 802.11 cellular 802.11 802.11, bluetooth -- unlicensed spectrum Technical Approach • Use emerging short range wireless communication over unlicensed spectrum • Completely decentralized peer-to-peer solution – save centralized solution cost Alternate network selection depending of Information Type • Cellular  Point-to-point by net-id • Short-range  Geospatial/anonymous/location-based

  10. MP2P: Why now? • Revisit paradigm: “devices should be small, so put intelligence in infrastructure”

  11. Research Problems in Mobile P2P • Data modeling – • many simultaneous applications, • sensor- and human-generated information • Resource management (bandwidth, power, memory) • Participation incentives for brokers, • to achieve reasonable search coverage • Dynamic and adaptive use of fixed infrastructure • Managing Heterogeneity • Remote Querying • Privacy, security, HCI

  12. Focus of Mobi-dik • Information ranking • Ranking done by aggregating • demand, • temporal, • spatial, • novelty, • reliability factors pertaining to data items • Aggregation uses machine learning techniques • Independent of the network (b/t or wifi) • Consequences of ranking: • improved search • The important (most likely to be useful) information is saved and communicated • improved memory, bandwidth, power utilization

  13. Focus of Mobi-dik (cont.) • Bandwidth and Power management by dynamic adaptation of • Size of each transmission • Frequency of transmissions • Range of each transmission

  14. Talk outline cytuc Computational Transportation Science Mobi-dik Data Dissemination

  15. Application Capture (discovery) of competitive (on/off) physical resources • Competitive resource: at most one consumer a time (parking slot, cab-customer, cab) • Compare • discovery time without information • discovery time with information (clearly shorter, enables seeing around block) • Conveyed in MP2P fashion • With ranking • Without ranking • Conveyed by ideal client server

  16. Outline of rest of talk • Peer-to-peer Broadcast (PPB) – a bandwidth-sensitive MP2P algorithm • Comparison with Searching-without-Information and Ideal-central-server

  17. Resource report • Resource type (parking slot) • Transmission time • Location of resource

  18. Mobile P2PBroadcast • Resources periodically send reports to moving objects that pass within transmission range. • Moving objects periodically sort the reports according to their relevance and broadcast the top M reports.

  19. Elements of PPB • Relevance function • Broadcast period • Broadcast size (number of reports in a broadcast)

  20. Relevance Function Theorem: Assume: (1) Consumers arrive at R according to a Poisson process with intensity . (2) The average speed of the consumer is v. (3) A report Ris generated at location (0,0) and at time 0. Then: for a consumer that receives a(R)at time t and distance d from (0,0), the probability that the resource R is still available when the consumer reaches R is

  21. Power of relevance function • Broadcast size = 1

  22. 802.11 Throughput (Effective bandwidth)

  23. Relationship: Broadcast size to Broadcast period • Expected throughput of the wireless channel in an (802.11) ad-hoc network • Broadcast period depends on density, transmission range, size of broadcast, and is chosen to maximize E(Th)

  24. Outline • Peer-to-peer Broadcast (PPB) • Comparison with Ideal-central-server

  25. Comparison with Ideal Dissemination (Central-server) • In ideal dissemination, a report is immediately transmitted to all vehicles after it is generated by the resource. With very reasonable broker density (average inter-broker distance of 173 meters) and wireless transmission range (250 meters), the performance of the PPB reaches that of the ideal dissemination case.

  26. Relevant research work

  27. Mp2p vs. client-server • Mp2p advantages • Zero cost • Unregulated communication • No central database to maintain • Independent of infrastructure • Higher reliability • Privacy preservation • Mp2p disadvantages • Weaker answer-completeness guarantees

  28. Relationship to work on Mobile Ad Hoc Networks • Work mainly concerned with sending a message to an ip-address • In contrast, MP2P focuses on dissemination among a group interested peers

  29. Ip address Next hop 1234 C 2345 D Resource type Next hop 3456 B printer C music D restaurant B Resource Discovery in MANET A MANET routing protocol is augmented to enable addressing based on resource type or resource key rather than network ID B A A’s routing table C D

  30. Printer? Printer? Here! Printer? A B Printer? Printer? Here! Printer? Printer? Printer? Resource type Next hop printer B Construction and Maintenance of Routing Table • Problems when applied to our context: • Does not work when consumer and resource are disconnected. • Resources are transient. Consumer has to constantly poll. • Constructed routing structure easily becomes obsolete. • May take awhile to construct in Bluetooth networks

  31. Other relevant work • Manet’s bandwidth capacity • Power management in Manet’s • Data broadcasting

  32. Mp2p vs. sensor networks • Devices more powerful and reliable than sensors • Sensor network topology mostly static • Aggregate function computation vs. trigger firing

  33. Experimental MP2P projects (Pedestrians) • 7DS -- Columbia University (web pages) • iClouds – Darmstadt Univ. (incentives) • MoGATU – UMBC (specialized query processing, e.g., collaborative joins) • PeopleNet -- NUS, IIS-Bangalore (Mobile commerce, information type  location baazar) • MoB – Wisconsin, Cambridge (incentives, information resources e.g. bandwidth) • Mobi-Dik – Univ. of Illinois, Chicago (brokering, physical resources, bandwidth/memory/power management)

  34. Vehicular projects • Inter-vehicle Communication and Intelligent Transportation: • CarTALK 2000 is a European project • VICS (The Vehicle Information and Control System) is a government-sponsored system in Japan with an 11-year track record • FleetNet, an inter-vehicle communications system, is being developed by a consortium of private companies and universities in Germany • IVI (Intelligent Vehicle Initiative) and VII (Vehicle Infrastructure Integration), the US DOT • MP2P provides data management capabilities on top of these communication systems • Grassroots – Rutgers, p2p dissemination of traffic info to reduce travel times

  35. Conclusion -- IGERT • New Ph.D. program: • Computer Science + Transportation Science • Novel applications: • Traffic Management • Traveler services • Emergency response • Research Themes: • Information Management and Communication • Software Services • Human Factors • Intelligent Traveler Assistant

  36. Conclusion - Mobidik • Innovative aspects: • Information Ranking • Memory, Power, Bandwidth management • Performance comparison with • Flooding • Ideal central server • Blind search

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