Q: What network is used if I perform a storage migration to or from SMB 3.0?
A: Storage migration allows the migration of a virtual machine's (VM's) storage between any supported storage. This includes direct-attached, SAN-based and SMB 3.0 file shares. Storage migration utilizes whatever normal fabric is used to communicate with the storage, which in the case of SMB 3.0 would be whatever network adapter(s) that has a path to the SMB 3.0 file share.
There is no separate storage migration network. The benefit of using the standard methods to communicate with storage is if you have any kind of acceleration or optimization technology, then that will be used. For example, for SMB 3.0, if you are using SMB Direct or SMB Multichannel, then that will be utilized during a storage migration over SMB 3.0.