Since FDTD calculations use a high level of resources such as RAM, disk space and CPU time, a cluster of twelve single home computers was set up using Message Passing Interface (MPI). This software makes it possible to perform parallel computations by controlling the data transfer between the nodes within a network. The graph indicates the time required to perform a calculation, given the number of computers attached and whether linux or windows is the operating system. The example program is cpi, included with the open source mpi software. Cpi calculates the error in a standard pi calculation.

Number of Nodes: 15
Processor Type: Intel Pentium III™ 1GHz
Amount of RAM: 512Mb per node
Type of Network: Gigabit
Operating System: Fedora Core 4 (Linux)