Until recently VMware’s virtualization certification was the VMware Certified Professional (VCP). Recently, VMware announced a more advanced certification – the VCDX. To become a VCP you must complete an official VMware training course (online or in the classroom), then pass a certification test at a local training center.
The VCDX builds on the VCP. To become a VCDX, you must first be a VCP and then you are required to pass 2 more advanced tests and present a VMware Infrastructure Design plan to a certification board.
You can learn more about the VCP and VCDX certifications at the VMware Certification Portal.