Message Passing Systems
If you have access to networked computers that you want to use for parallel processing, you can examine the freely available message passing systems. Parallel Virtual Machine (PVM) is one such system, available at http://www.epm.ornl.gov/pvm/ and http://www.netlib.org/pvm3/index.html. On the other hand, Message Passing Interface (MPI) is technically not a system, but a standardized interface. For information on MPI, see http://www-unix.mcs.anl.gov/mpi/. There are two freely available implementations, MPICH (ftp://ftp.mcs.anl.gov/pub/mpi) and LAM/MPI (http://www.mpi.nd.edu/lam/).
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