An isotach implementation for myrinet

An isotach network provides strong guarantees about message delivery order. We show that an isotach network can be implemented efficiently entirely in software, using commercial o-the-shelf hardware. This report describes that effort. Parts of this implementation could be performed much more efficiently in hardware; we are currently developing custom hardware components to do this. The all-software version then serves several purposes: to develop a working isotach system rapidly, for use as a platform for development of higher level software to find potential problems in the hardware design to pre-test software components of the system so that they will not have to be de-bugged at the same time as hardware to achieve as much performance as possible without hardware acceleration The implementation was successful; it works, and performs well. A number of features that will be present in the hardware version are not yet implemented; they will be added in the near future.