Wikipedia
VXS
VMEBus Switched Serial, commonly known as VXS, is an ANSI standard (ANSI/VITA 41) that improves the performance of standard parallel VMEbus by enhancing it to support newer switched serial fabrics. The base specification (ANSI 41) defines all common elements of the standard, while "dot"-specifications (ANSI 41.n) define extensions which use specific serial fabrics (such as PCI Express, RapidIO, StarFabric and InfiniBand) or additional functionality. VXS is backward compatible with VMEBus. It is defined by the VITA (VME International Trade Association) working group.