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Articles 1 - 7 of 7
Full-Text Articles in Physical Sciences and Mathematics
Toward Dynamic Interoperability Of Mobile Agent Systems, Arne Grimstrup, Robert Gray, David Kotz, Maggie Breedy, Marco Carvalho, Thomas Cowin, Daria Chacon, Joyce Barton, Chris Garrett, Martin Hofmann
Toward Dynamic Interoperability Of Mobile Agent Systems, Arne Grimstrup, Robert Gray, David Kotz, Maggie Breedy, Marco Carvalho, Thomas Cowin, Daria Chacon, Joyce Barton, Chris Garrett, Martin Hofmann
Dartmouth Scholarship
Mobile agents are an increasingly popular paradigm and in recent years there has been a proliferation of mobile-agent systems. These systems are, however, largely incompatible with each other. In particular, agents cannot migrate to a host that runs a different mobile-agent system. Prior approaches to interoperability have tried to force agents to use a common API and so far none have succeeded. This goal led to our efforts to develop mechanisms that support dynamic runtime interoperability of mobile-agent systems. This paper describes the \em Grid Mobile-Agent System, which allows agents to migrate to different mobile-agent systems.
Analysis Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien
Analysis Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien
Dartmouth Scholarship
Understanding usage patterns in wireless local-area networks (WLANs) is critical for those who develop, deploy, and manage WLAN technology, as well as those who develop systems and application software for wireless networks. This paper presents results from the largest and most comprehensive trace of network activity in a large, production wireless LAN. For eleven weeks we traced the activity of nearly two thousand users drawn from a general campus population, using a campus-wide network of 476 access points spread over 161 buildings. Our study expands on those done by Tang and Baker, with a significantly larger and broader population. \par …
Future Directions For Mobile-Agent Research, David Kotz, Robert Gray, Daniela Rus
Future Directions For Mobile-Agent Research, David Kotz, Robert Gray, Daniela Rus
Dartmouth Scholarship
The field of mobile agents should shift its emphasis toward mobile code, in all its forms, rather than continue focusing on mobile agents. The development of modular components will help application designers take advantage of code mobility without having to rewrite their applications to fit in monolithic, mobile agent systems.
Three Power-Aware Routing Algorithms For Sensor Networks, Javed Aslam, Qun Li, Daniela Rus
Three Power-Aware Routing Algorithms For Sensor Networks, Javed Aslam, Qun Li, Daniela Rus
Dartmouth Scholarship
This paper discusses online power‐aware routing in large wireless ad hoc networks (especially sensor networks) for applications in which the message sequence is not known. We seek to optimize the lifetime of the network. We show that online power‐aware routing does not have a constant competitive ratio to the off‐line optimal algorithm. We develop an approximation algorithm called max–min zPmin that has a good empirical competitive ratio. To ensure scalability, we introduce a second online algorithm for power‐aware routing. This hierarchical algorithm is called zone‐based routing. Our experiments show that its performance is quite good. Finally, we …
Solar: An Open Platform For Context-Aware Mobile Applications, Guanling Chen, David Kotz
Solar: An Open Platform For Context-Aware Mobile Applications, Guanling Chen, David Kotz
Dartmouth Scholarship
Emerging pervasive computing technologies transform the way we live and work by embedding computation in our surrounding environment. To avoid increasing complexity, and allow the user to concentrate on her tasks, applications in a pervasive computing environment must automatically adapt to their changing \em context, including the user state and the physical and computational environment in which they run. Solar is a middleware platform to help these “context-aware” applications aggregate desired context from heterogeneous sources and to locate environmental services depending on the current context. By moving most of the context computation into the infrastructure, Solar allows applications to run …
Mobile Voice Over Ip (Mvoip): An Application-Level Protocol For Call Hand-Off In Real Time Applications, G. Ayorkor Mills-Tettey, David Kotz
Mobile Voice Over Ip (Mvoip): An Application-Level Protocol For Call Hand-Off In Real Time Applications, G. Ayorkor Mills-Tettey, David Kotz
Dartmouth Scholarship
This paper presents Mobile Voice Over IP, an application-level protocol to support terminal mobility in real-time applications such as voice over IP, on a wireless local area network. We describe our MVOIP implementation based on the ITU-T H.323 protocol stack, present experimental results on call hand-off latency, and discuss various implementation issues, including the task of quickly and accurately determining when call hand-off is necessary. We also discuss how MVOIP relates to other proposed mobility support schemes, and how it can be generalized to provide application-level mobility support in a wide range of real and non real-time applications.
Armada: A Parallel I/O Framework For Computational Grids, Ron Oldfield, David Kotz
Armada: A Parallel I/O Framework For Computational Grids, Ron Oldfield, David Kotz
Dartmouth Scholarship
High-performance computing increasingly occurs on “computational grids” composed of heterogeneous and geographically distributed systems of computers, networks, and storage devices that collectively act as a single “virtual” computer. One of the great challenges for this environment is to provide efficient access to data that is distributed across remote data servers in a grid. In this paper, we describe our solution, a framework we call Armada. Armada allows applications to flexibly compose modules to access their data, and to place those modules at appropriate hosts within the grid to reduce network traffic.