High performance concurrent multi-path communication for MPI

MPI is the most generally accepted API in HPC. Today, a typical HPC platform provides a hierarchy of parallelism and networks, from OnChip Networks, SMPs, SAN to WAN. The MPI protocol stack has been optimized for shared memory plat-forms, InfiniBand etc. WAN MPI still is an extension of LAN MPI and thus uses TCP. MPI in WANs is important because large cross-site resource pools often are used in Cloud and Grid Computing. Therefore MPI performance/ reliability/security in WANs must be addressed, and that's what we do and present here.