View source for HPC Glossary/Infiniband

'''Infiniband''' and '''Omni-Path''' are a high-speed Network often used in HPC systems for their low latency. The name comes from "infinite bandwidth", because you can connect several cables to the same machine, up to a theoretical infinite bandwidth. 

'''Infiniband''' is the original network distributed by Melanox (now part of Nvidia).

'''Omni-Path''' or '''OPA''' is about the same technology originally created by Intel, but now sold by a separate company Cornelis Networks. 

Infiniband/Omni-Path do not natively use the TCP protocol, but RDMA ("remote direct memory access"), but TCP/IP is normally provided on top. 

Usual setups reserve the high-speed network for compute jobs and data transfer with the file systems, while ssh connections and other maintenance connections happen via a standard ethernet connection to the compute nodes. 


See wikipedia articles for more detailed information:

* https://en.wikipedia.org/wiki/InfiniBand 
* https://en.wikipedia.org/wiki/Omni-Path
* https://en.wikipedia.org/wiki/Remote_direct_memory_access