| Popis: |
Network simulation continues to be the dominant method of experimental evaluation in wireless networking. However, much research has established the failure of simulator models to adequately express wireless signal propagation. These shortcomings can lead to incomplete evaluation of wireless protocols and applications. When wireless research includes mobility, real evaluation becomes still more difficult due to the difficulty of creating and controlling mobile nodes in a real environment. The primary goal of Mobile Emulab, the testbed presented in this thesis, is to encourage real mobile wireless research in the wireless community and provide a sound, usable testbed platform for experimentation. Mobile Emulab is both software designed to control and monitor a mobile wireless testbed, and a testbed providing access to mobile wireless resources. The testbed consists of several robots, each with a small computer and small wireless devices called motes, manueverable in an area surrounded by fixed motes. Through a variety of interfaces, remote researchers can control these robots interactively over the Web. Mobile Emulab provides an overhead tracking system that localizes the robots to within 1 cm, providing repeatable positioning and valuable knowledge to researchers studying how signal propagation affects their experiments. Additional software tools that were developed to ease the evaluation process for wireless sensor network researchers can be used by Mobile Emulab experimenters. Finally, the testbed extends Emulab, which provides researchers with well-known experimental interfaces and automation capabilities. This thesis presents Mobile Emulab's design and implementation, and establishes its usability and utility through several experiments. |
