It is possible to import a dvSwitch into a data center from a configuration backup. Unlike the restore operation, which can only be done on a dvSwitch, the import operation can be performed on a data center with or without existing Distributed Switches in them. This functionality comes in handy if you want to create a similar dvSwitch in a different data center.
Refer to the Creating vSphere Distributed Switch backup recipe to learn how to back up a dvSwitch.