All sensor data is collected and archived at a central server and exposed to the user through the CarTel AutoPortal. The screen shots below show a prototype interface that allows users to view routes they have taken. Each route has "data overlays" that correspond to the sensor data being collect by the remote nodes. For example, users can overlay engine performance metrics on these routes to visualize changes as a function of time and geography.
For more details, see the CarTel site.
The CarTel mobile sensor computing system builds on ideas from many research areas.
There has been much written about deploying sensor systems for environmental monitoring and data collection [1,2]. For the most part, these systems are focused on low-data rate sensing and power management issues.
In the area of query processing, our system extends many of the ideas pioneered in such continuous query engines as [3,4,5]. However, unlike most traditional systems, CarTelDB pushes into new areas by treating intermittent connectivity as a fundamental property of the system that must be exploited rather than masked or considered a failure.
In the area of networking, there have been several proposals for delay tolerant network stacks including . In addition, there has been some initial work that explores sending data in a mobile context using opportunistic Wi-Fi  as well as through occasionally connected data mules . CafNet applies and extends these ideas using a novel application programming interface and works over a variety of networking technologies.
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This work is funded in part by Quanta Corporation and by the National Science Foundation under Award Number CNS-0205445.
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