Reliant Technology - SAN vs NASSAN vs. NAS Essentials

Storage area network (SAN) is a high-speed storage device network connecting servers with storage devices. Applications on any networked server can access SAN’s block-level storage and use standard file-system protocols such as Network File System and Server Message Block protocols over IP networks.

An essential function is to permit storage devices to communicate with each other and also with computer systems. SAN facilitates universal connectivity, linking many computers to many storage devices, and enabling devices and data to be shared.

Network-attached storage (NAS) employs a standard Ethernet connection with file-based shared storage services. NAS systems are not well suited for applications that must access block-level storage. NetApp has added block-level protocol to their NAS filers in order to attract a portion of profitable SAN market. NAS is both horizontally and vertically scalable by using large disks or through clustering.

Use Cases for NAS and SAN

High end NAS is occupied by businesses that have massive storage needs, including virtual machine images. Upper tier NAS offers rapid access and clustering capabilities.

The low end of the NAS market targets small businesses and home users requiring local shared storage. In this market segment cloud NAS is playing a greater part. NAS is often used for smart home functionality and for centralized storage. Related tasks include support for security systems, Internet of Things and storing and serving multimedia files.

SAN is likely to be appropriate in a data center supporting multiple critical applications for which downtime might be more than costly. Upfront costs for implementing a SAN-based disaster recovery solution are high, but so are the benefits.  They can be recouped in a single hour when disaster strikes. A SAN-based disaster recovery solution can be the best insurance policy a company could have.

Convergence of function

In the same way as NetApp, SAN vendors have been adding file-system protocol support to their SAN platforms. To gain market share, an ever increasing number of manufacturers of shared storage platforms are supporting both block and file level protocols. With SAN and NAS each striving to support their rival’s storage architecture, the world of network storage appears to be converging.

Many common features - choose most appropriate for target function

NAS and SAN systems have much in common. They share features like snapshots, thin provisioning and replication. Companies that need to process unstructured data, such as text-heavy data, will find NAS a substantially better choice than SAN.  With SAN, it’s easier to share block-level storage, SAN being more versatile than NAS - its primary use is for data consolidation. Both SAN and NAS offer shared storage.