Towards ´Phenomenaria´ in the teaching of distributed systems concepts

Any learning environment can be parsed into five facets. These five facets are information banks, symbol pads, construction kits, ´phenomenaria´ and task managers. ´Phenomenaria´ are areas for the specific purpose of presenting phenomena and making them accessible to scrutiny and manipulation. Taken together these five facets offer a perspective on the general structure and style of the learning environment. A collection of processes, which are distinct, spatially separated, and which communicate by exchanging messages constitutes a distributed system. A distributed algorithm defines the steps to be taken by each process within that system, including the transfer of messages. It must be able to deal with the failure of one or more of the processes involved in its computation and also the failure of one or more message transmissions. A major problem in teaching the latter material is the ability to capture the dynamic movement of data. Typically, when demonstrating data movement on a white board, part of the existing data configuration must be erased in order to show the new configuration. A phenomenarium offers a way forward for both lecturers and students in that it provides mechanisms not only to animate but to simulate dynamic movement in visual form. Moreover, it can be housed within an environment that permits ´anytime anywhere´ learning, like the World Wide Web. Simply stated, a phenomenarium permits a student to interact with elements of a given algorithm in their own time. An argument in favor of the use of the latter in the teaching of distributed algorithms is presented.