GridMathematica

gridMathematica is a product sold by Wolfram Research which is based on its main product Mathematica. gridMathematica has additional features which allow a cluster of computers to work in parallel to solve some types of problems in less time than would be possible using just one. One front end is used to communicate with multiple kernels, which actually perform the computations.The computers do not need to run the same operating systems.

A major component of gridMathematica is the Parallel Computing Toolkit developed by Roman Maeder, who is one of the original authors of Mathematica. An earlier version of the Parallel Computing Toolkit is available free, whereas the latest version is sold.

The communication between the kernels and the front end uses the Mathlink interface, which is an interface designed to allow external programs to communicate with Mathematica. The communication is over TCP/IP and would use SSH or RSH for authentication.

A very similar product is Mathematica Personal Grid Edition, but whereas Mathematica Personal Grid Edition can only use multiple processors on the one computer, gridMathematica can use multiple processors on multiple computers. The Mathematica Personal Grid Edition and gridMathematica are essentially the same, but gridMathematica includes additional licenses to allow the other kernels to work.

There is a free seminar delivered over the web describing examples of how to use gridMathematica or Mathematica Personal Grid Edition.