VPX, also known as VITA 46, is an ANSI standard (ANSI / VITA 46.0-2007) created to replace the VME bus. Defined by the international organization VITA, this standard was developed with the collaboration of the main sub-contractors of the defense and aeronautics industry, and was specifically designed for military applications. VPX maintains the 6U and 3U formats typical of the VME bus and supports existing PMC and XMC mezzanines.

The new generation of VPX-based systems use synchronous serial protocols such as PCI Express and RapidIO for communication between cards. These communication technologies are in fact replacing traditional parallel buses.

The main features of VPX are:

• 3U and 6U format
• New 7-column connector that supports signals up to 6.25 Gbit / s
• Numerous choices of protocols to use
• Mezzanines PMC, FMC (VITA 57) and XMC (VITA 42)
• Hybrid backplanes to maintain compatibility with VME, VME64 and VXS.