Robot and sensor networks are needed for safety, security, and rescue applicationssuch as port security and reconnaissance during a disaster. These applications rely on realtimetransmission of images, which generally saturate the available wireless networkinfrastructure. Knowledge-based Compression is a strategy for reducing the video frametransmission rate between robots or sensors and remote operators. Because images mayneed to be archived as evidence and/or distributed to multiple applications with differentpost processing needs, lossy compression schemes, such as MPEG, H.26x, etc., are notacceptable. This work proposes a lossless video server system consisting of three classesof filters (redundancy, task, and priority) which use different levels of knowledge (localsensed environment, human factors associated with a local task, and relative globalpriority of a task) at the application layer of the network. It demonstrates the redundancyand task filters for realistic robot search scenarios. The redundancy filter is shown toreduce the overall transmission bandwidth by 24.07% to 33.42%, and when combinedwith the task filter, reduces overall transmission bandwidth by 59.08% to 67.83%. Byitself, the task filter has the capability to reduce transmission bandwidth by 32.95% to33.78%. While Knowledge-based Compression generally does not reach the same levels ofreduction as MPEG, there are instances where the system outperforms MPEG encoding.

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Virtual machines are gaining a growing importance in modern business IT infrastructure. They facilitate multiple operating system instances on one physical host, which provides more efficient use of the computing power of the physical host but increases the amount of network traffic as well. To avoid potential network congestion and prioritize link resource usage in a virtual machine system, we propose a bandwidth regulation scheme. Extensive evaluation demonstrates that this bandwidth regulation scheme is accurate and effective. In addition, we resolved a drastic performance degradation of the Open-iSCSI initiator. We thoroughly tested the performance of the Open-iSCSI initiator and three modified versions under two methods of setting the TCP send buffer size - statically and dynamically. Based on these results, we propose a performance tuning scheme, which can enable users of Open-iSCSI, especially those using Open-iSCSI over a long fat network, to achieve significant throughput gains.