A Virtual Interface Adapter (VIA) is a network protocol (such as TCP/IP ...).
In general, it is usually a network kind of interface but is usually a very high-performance, dedicated connection between two systems.
Part of that high performance comes from specialized, dedicated hardware that knows that it has a dedicated connection and therefore doesn't have to deal with normal network addressing issues.
Comes in the concept of clustering (i.e.) load balancing method.
You can help Wikipedia by expanding it.This computing article is a stub.