An Input/Output (IO) Virtualization (IOV) system provides a mechanism for sharing computer peripheral devices or resources between multiple host computers by presenting a single resource multiple times to numerous host systems. The IOV system provides IO virtualization and host-to-host communication services to the host computers. The system comprises device interfaces coupled to the IO devices. Each IO device comprises at least one endpoint function (EPF). Host interfaces are each coupled to one of a number of host computers. Each host interface includes a proxy, and each proxy comprises configuration data.