Which two block storage protocols are supported on vSphere?

vSphere supports several block storage protocols, but to clarify, the correct focus should be on the specific protocols that directly align with block storage technologies.

Single-Access Networks, commonly recognized as SAN (Storage Area Networks), is a significant protocol that vSphere supports. SAN enables multiple servers to communicate with storage devices on a high-speed network. This allows for efficient data sharing and management close to the performance of direct-attached storage, which is why SAN is considered one of the key block storage protocols within the vSphere environment.

When considering the other options, it's important to note that protocols like SMB and NFS are typically associated with file storage rather than block storage. NFSv4.1 and NFSv3, for instance, are network file system protocols that facilitate file-level access and management instead of block-level. iSCSI (Internet Small Computer System Interface), while also a valid block storage protocol and commonly used, was not selected in this context.

Therefore, the identification of SAN as a block storage protocol is correct in distinguishing the core technology that vSphere leverages to provide robust storage solutions suited for virtualization environments.