A Virtual Interface Adapter ("VIA") is a network protocol (such as TCP/IP ...). As of July 2006 Microsoft SQL Server 2005 supports it. The specific implementation of VIA will vary from vendor to vendor. 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. [1]
The VIA protocol is used to support VIA devices such as VIA Storage Area Network devices.
Note that the VIA protocol is deprecated by Microsoft, and will be removed in a future version of Microsoft SQL Server. It is however supported in SQL Server 2008 and SQL Server 2008 R2. [2]