A DistributedVirtualSwitch is the base distributed switch implementation. It supports a VMWare distributed virtual switch and it supports third party switch implementations.
A VmwareDistributedVirtualSwitch is a sub-type of DistributedVirtualSwitch, and only supports a VMWare distributed virtual switch.
From the vmware sdk, we got following messages:
A DistributedVirt ualSwitch is the base distributed switch implementation. It supports a VMWare distributed virtual switch and it supports third party switch implementations.
A VmwareDistribut edVirtualSwitch is a sub-type of DistributedVirt ualSwitch, and only supports a VMWare distributed virtual switch.