CyberCertPrepNetwork FundamentalsNetwork DevicesEASYFree question
What is a NAS (Network Attached Storage) device, and how does it differ from a SAN (Storage Area Network) in terms of protocol and access model?
- A.NAS uses Fibre Channel for block storage while SAN uses NFS for file storage over IP
- B.NAS presents file-level storage over IP using protocols like NFS (TCP 2049) or SMB (TCP 445); SAN presents block-level storage over Fibre Channel or iSCSI, appearing as a local disk to servers
- C.NAS and SAN are identical; the difference is only in capacity and vendor branding
- D.NAS operates at OSI Layer 1 for direct-attached storage; SAN operates at Layer 3 for IP-based storage
Why B is correct
NAS = Network Attached Storage, file-level, IP-based, protocols NFS (Linux/Unix) and SMB/CIFS (Windows). SAN = Storage Area Network, block-level, Fibre Channel or iSCSI. Servers see SAN LUNs as raw block devices (like a local hard drive), while NAS appears as a mounted share. Options B, C, and D invert or conflate the definitions.
Know someone studying for Network Fundamentals? Send them this one.