A block-level storage protocol leverages existing network infrastructure (like Ethernet) to connect servers to storage devices. This allows a server to access storage located on a separate physical machine as if it were a directly attached hard drive. In a Windows Server environment, this capability is provided through a software component enabling the server to offer storage to other network devices. For example, a Windows Server can be configured to present a portion of its local storage to a virtual machine running on a separate physical server. The virtual machine would then see this storage as a locally attached disk.
This network-based storage approach offers several advantages including centralized storage management, resource consolidation, enhanced flexibility, and potentially lower costs. Historically, SAN technologies like Fibre Channel dominated block-level storage networking. However, the relative simplicity and cost-effectiveness of using existing Ethernet networks have made this protocol an increasingly popular alternative, particularly in smaller and medium-sized deployments. This technology eliminates the need for specialized hardware and expertise associated with traditional SANs.