Along with our colleagues at the Oregon Graduate Institute and Georgia Institute of Technology, we have recently been experimenting with real-rate systems, that is, systems that are required to move data from one place to another at defined rates, such as 30 items per second. Audio conferencing or streaming video systems are typical: they are required to deliver video or audio frames from a source (a server or file system) in one place to a sink (a display or a sound generator) in another; the frames must arrive periodically, with constrained latency and jitter. We have successfully built such systems (for example, see reference [Walpole 1997]), but they are not simple to design or construct. Our current research seeks to capture our knowledge of this domain into an information flow framework, called InfoPipes. The goal of Infopipes is to make the task of building a system that moves data from one part of the Internet to another as simple as connecting pre-defined components such as buffers, pipes, filters and meters. The latency, jitter and data-rate properties of the resulting pipeline should follow by calculation from the properties of the components
