Demo and Exhibitions
MobiCom 2004 will include demonstrations of some of the best of state-of-the-art research in the field of mobile computing and wireless and mobile networking. The following demos have been accepted for presentation at the conference:
- TrafficView: How Far Can You See?
Authors: Tamer Nadeem (Department of Computer Science, University of Maryland), and Porlin Kang, Cristian Borcea, and Liviu Iftode (Department of Computer Science, Rutgers University
Vehicles are part of people's life in the modern society, into which more and more high-tech devices are integrated. A common platform for inter-vehicle communication is necessary to realize an intelligent transportation system supporting safe driving, dynamic route scheduling, emergency message dissemination, and traffic condition monitoring. TrafficView, which is a part of the e-Road project, defines a framework to disseminate and gather information about the vehicles on the road using only vehicle-to-vehicle communication. This system provides a vehicle driver with road traffic information, which helps driving in situations as foggy weather, or finding an optimal route in a trip several miles long.
The goal of this demo is to illustrate the use of TrafficView in real world traffic scenarios. The demo will demonstrate how TrafficView displays the traffic information even in situations where the cars ahead of a certain car are not physically visible from that car. The demo will consists of two parts: 1) A number of movies that show, in parallel, the cars on the road and the information displayed by TrafficView in one of those cars. Each movie corresponds to a different traffic scenario. 2) An emulation of the same traffic scenarios using HP iPAQs that will represent the computers embedded in cars. Each iPAQ will display the information corresponding to one car. TrafficView will be adapted to work indoors.
- Asset Tracking via Robotic Location Crawling
Authors: Abhishek Patil, Jonathan Munson, David Wood, and Alan Cole
Asset tracking - knowing what you have and where it is located - is essential for the smooth operation of many enterprises. From manufacturers, distributors, and retailers of consumer goods, to government departments, enterprises of all kinds are gearing up to use RFID technology to increase the visibility of goods and assets within their supply chain and on their premises. However, RFID technology alone lacks the capability to provide the location of items once they are moved within a facility. Furthermore, in most situations, it is prohibitively expensive to continuously track an item. However, a periodic (say nightly) recording of location is sufficient for many tracking applications. There are now available off-the-shelf Wi-Fi-based location sensing systems which locate Wi-Fi devices with an accuracy of few meters. We present a prototype system that combines such a location positioning system and RFID technology to provide a periodic asset location sweep. The prototype system not only identifies but also provides location information of every RFID-tagged item in the swept space. In our demo, a laptop running a Wi-Fi client and connected to an RF reader is mounted on a robot (Roomba Robotic FloorVac) that moves autonomously through the space. As the robot moves, the RF reader periodically samples which tags are detectable. At each sample time, the robot's position is obtained from the positioning system. An algorithm combines detected tag readings with previous samples and computes the location of detected tags and updates a tag database.
- Ant Routing Algorithm ARA
Authors: Mesut Günes, and Imed Bouazizi
The Ant-Routing-Algorithm (ARA) is highly adaptive, efficient and scalable. It is based on swarm intelligence. ARA consists of three phases. i) Route Discovery Phase: In this phase new routes are discovered in the network. The discovery of new routes requires the use of a forward ant (FANT) and a backward ant (BANT). A FANT is an agent which establishes the pheromone track back to the source node. Analogously, a BANT establishes the pheromone track back to its origin, namely the destination node. ii) Route Maintenance: This phase is responsible for the maintenance of the routes during the communication. iii) Failure Handling: This phase handles routing failures which are especially caused by node mobility.
We demonstrate the feasibility of ARA by implementing a distributed chat application over an ad-hoc network. Interested users are given a Pocket PC device and are asked to start the application and choose an appropriate name and nickname for chatting. The users are then allowed to move around and send chat messages to other users in the ad-hoc network.
Our application was developed to run over Pocket PC devices, which have a (built-in or external) W-LAN 802.11b compatible interface. The devices should have support for point-to-point wireless communication, which is used to build an ad-hoc network. This is usually supported by all common W-LAN network interfaces.
- Passive Autoconfiguration for Mobile Ad hoc Networks (PACMAN)
Authors: Kilian Weniger, Ingmar Baumgart and Martina Zitterbart (Institute of Telematics, University of Karlsruhe, Germany)
Mobile ad hoc networks enable the establishment of a communication network independent of any infrastructure in a spontaneous manner. Thus, the network must be able to autoconfigure. Most importantly, the nodes must be configured with unique IP adresses. Passive Autoconfiguration for Mobile Ad hoc Networks (PACMAN) is an efficient and robust distributed solution to the IP address autoconfiguration problem. PACMAN heavily uses cross-layer information from ongoing routing protocol traffic: The allocation table as well as the Duplicate Address Detection (DAD) are performed in a passive manner and therefore generate almost no additional communication overhead. The Passive DAD (PDAD) is able to detect address conflicts (occurring e.g. after network mergers) based on anomalies in the routing protocol traffic. Different routing protocols are supported by PACMAN. However, a modification of the message format or the implementation of the routing protocol is not necessary.
We present a prototype system consisting of ten Pocket PCs equipped with Wireless LAN adapters, which run the Linux operating system, a well-known RFC-complaint Optimized Link State Routing (OLSR) protocol implementation and an implementation of PACMAN. A QT/Embedded-based GUI has been developed that displays various statistics and parameters. The GUI can also be used to set various parameters, automatically aquire a new IP address or manually assign one. To demonstrate mobility as well as network partitioning and merging in a small scale, different network topologies can be emulated and visualized using a tool called Wireless Network Topology Emulator (WNTE).
Using Ad Hoc Networking in Orienteering
Authors: Christian Rohner, Erik Nordström, and Henrik Lundgren
Competitive orienteering is a sport that involves using a map and a compass to navigate one's way round a course with designated control points which are drawn on the map. On the route, control markers are set in the places that correspond to the points on the map. The winner of the competition is the participant who has used the shortest time to visit the control points in numerical order.
We apply ad-hoc networking to the sport of orienteering to provide an on-line information system. This interactive demo integrates ad-hoc networking using our AODV-UU implementation, interconnection between ad-hoc networks and the Internet, and aspects of self-configuration such as address assignment and service discovery. Demo visitors can participate in a small competition by going with an RFID-tag in their hand from one ad-hoc node (i.e., control point) to another. Each ad-hoc node will report a participant's visit to the demo booth where the competition can be followed in realtime on a scoreboard.
A Demonstration of Position Tracking Using the Cricket Indoor Location
Authors: Elizabeth M. Belding-Royer
Cricket is an indoor location system that tracks the position of devices and sensors to within a few centimeters of accuracy. The system consists of beacons that are mounted on walls and ceilings that transmit location information, and listeners that are attached to mobile objects. The listeners use the information broadcast from the beacons to estimate their distances to each beacon, and use distances from multiple beacons to infer their positions.
One of the key challenges in Cricket is to develop a localization algorithm that accurately computes the position of the listeners in the face of asynchronous beacon broadcasts and distance measurement errors. Another challenge in Cricket is to automate the process of computing and programming the beacons' coordinates. This demonstration will show these techniques.
We have also developed an extended Kalman filter for Cricket that can track a moving listener's position with high accuracy and low delay. Our filter works well even when beacons take turns randomly to broadcast their signals to the listeners. The demonstration will show this technique in action, in the context of tracking a moving toy train.
Physical Implementation of Ad Hoc Network
Routing Protocols using Unmodified ns-2 Models
Authors: Amit Kumar Saha, Khoa To, Santashil PalChaudhuri, Shu Du, and David B. Johnson (Rice University Houston, Texas)
Evaluating ad hoc network routing protocols is difficult due to the complexity of possible network topology changes and the resulting protocol interactions. The most common method of evaluation, network simulation, allows repeatable experiments but may fail to capture the precise behavior of the real system. On the other hand, physical protocol implementation allows the real system itself to be measured and tested but is much more time- and equipment-intensive and is generally much more difficult. To address this conflict between simulation and physical implementation, we have developed a system that allows existing simulation models of ad hoc network routing protocols to be used--without source code modification--to create a physical implementation of the same protocol. We have evaluated the simplicity and portability of our approach across multiple routing protocols and multiple operating systems through example new physical implementations of the DSR and AODV routing protocols in both FreeBSD and Linux using the existing, unmodified ns-2 simulation models of these protocols. The user-level code is identical between our implementations on FreeBSD and Linux, and the small amount of new operating system kernel support code required by our system is identical for all protocols. We will demonstrate our system, illustrating its ability to handle real, demanding applications, by showing our new DSR implementation transmitting real-time video over a mobile, multihop ad hoc network including mobile robots being remotely operated based on the transmitted video stream. All video and robot control messages are transmitted over the ad hoc network running our new DSR implementation.