Multimedia streaming applications can consume a significant amount of server and network resources. Periodic broadcast and patching are two approaches that use multicast transmission and client buffering in innovative ways to reduce server and network load, while at the same time allowing asynchronous access to multimedia streams by a large number of clients. Current research in this area has focussed primarily on the algorithmic aspects of these approaches, with evaluation performed via analysis or simulation. In this paper, we describe the design and implementation of a flexible streaming video server and client test bed that implements both periodic broadcast and patching, and explore the issues that arise when implementing these algorithms using laboratory and internet-based test beds. We present measurements detailing the overheads associated with the various server components (signaling, transmission schedule computation, data retrieval and transmission), the interactions between the various components of the architecture, and the overall end-to-end performance. We also discuss the importance of an appropriate server application-level caching policy for reducing the needed disk bandwidth at the server. We conclude with a discussion of the insights gained from our implementation and experimental evaluation.

Games can be a valuable tool for enriching computer science education, since they can facilitate a number of conditions that promote learning: student motivation, active learning, adaptivity, collaboration, and simulation. Additionally, they provide the instructor the ability to collect learning metrics with relative ease.

We present Grimiore, a web-based frontend for the disk imaging software Clonezilla. Grimiore was created to maintain computer labs in an academic setting. Each class had different needs for software and operating systems, yet classes compromise on what is installed so they can coexist in the same lab. Reinstalling the operating systems on the lab computers takes too long to be done daily, for each class. Labs, which are maintained by the professors, also face the problem of malfunctioning computers, and the time needed to troubleshoot the issue or reinstall the computer's operating system is often not available during the semester.Grimiore allows administrators to restore and maintain an entire lab of computers, rather than a single computer or a single homogenous image.Administrators can create a lab configuration for each use of the lab, and restore them with a single option.Grimiore stores configuration data for each computer in each class, allowing lab configuration to contain heterogeneous images.Finally, Grimiore is web-based and provides administrative control over the entire imaging system, as well as user level control over a single client computer. Professors can modify entire labs with one operation. Students can repair the computer they are logged into.

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