Presented by Chih-Yu Lin 788.11J Presentation “CarTel: A Distributed Mobile Sensor Computing System” Presented by Chih-Yu Lin Hello everyone. I will present the CarTel Project developed by MIT and the paper will be published on SenSys conference this year. In this project, a distributed mobile sensor computing system was implemented. Bret Hull, Vladimir Bychkovsky, Yang Zhang, Kevin Chen, Michel Goraczko, Allen Miu, Eugene Shih, Hari Balakrishnan and Samuel Madden, “CarTel: A Distributed Mobile Sensor Computing System”, SenSys’06

The Main Idea Mobile Heterogeneous sensor data Mobile sensor networks offer the potential to cover a much larger geographical area with a smaller number of sensors Heterogeneous sensor data CarTel should not constrain sensor data types A CarTel node is a mobile embedded computer coupled to a set of sensors Support intermittent connection Now I present the main idea of the CarTel project.In static sensor network, if we want sensors to cover a large area, we need to deploy large number of sensors. So an alternative is using mobile sensors. For example, we can just dispatch one mobile sensor to that area, and the mobile sensor will travel at that area, collect data, process data, and store data locally. Then when the mobile sensor returns to the portal, it can transmit the data to the portal so that the user can retrieve the data. So mobile sensor networks offer the potential to cover a much larger geographical area with a smaller number of sensors. In addition, CarTel should not constrain sensor data types. For example, the mobile sensor should have the ability to measure the light level, temperature, humidity, and so on. If a user want to sense a new data type, the user can just install a new sensor into the CarTel node.

The Main Achievements What did this work accomplish? ICEDB (intermittently connected database) A delay-tolerant continuous query processor CafNet (carry-and-forward network) a delay-tolerant network stack Portal Data visualization In order to achieve this goal, three components were implemented. The first one is ICEDB. Intermittently Connected Database. ICE

The Challenges Provide a simple programming interface Application developers should not have to deal with distribution or mobility Handle intermittent connectivity The primary mode of network access is via opportunistic wireless Handle large amounts of heterogeneous sensor data should make it easy to integrate new kinds of sensors, new mobile nodes, and new data types into the system

Technology that makes CarTel possible A 586-class processor running at 266 MHz with 128 MB of RAM and 1GBytes of flash memory GPS miniPCI Wi-Fi Card OBD-interface

A geo-spatial data virtualization system