Cloud NAS (network attached storage) is remote storage that is accessed over the Internet as if it was local. The storage is usually hosted by a third-party service provider, who charges the customer a fee based on capacity and bandwidth. In the enterprise, the off-site storage might be proprietary, but the chargeback method would be similar.
A cloud NAS storage-as-a-service is often used for backups and archiving. A key benefit is that data in the cloud can be accessed at any time from any place. The main drawback, however, is that the data transfer rate (DTR) is only as fast as the network connection the data is accessed over.