The newly released iMac Pro has a built-in 10Gb Ethernet connector, making it easier than ever to use shared NAS storage.
But if you are mounting your Volume using SMB, you may not be able to use the full speed. The reason is that by default, since macOS 10.11, SMB signing is turned on, which slows down the communication.
When SMB signing is turned on, all SMB packets are signed, and thus it makes secure communications between two devices. This is mainly useful if you connect through an unsecured network. If your network is secure, and you want to enjoy all the speed of SMB, follow the instructions in the following article to disable SMB signing:
Note that disabling SMB signing will also speed up 1Gb networks, but it is much clearer an important with 10Gb connections.