Storage Area Network (SAN)

What Does Storage Area Network (SAN) Mean?

A storage area network (SAN) is a secure high-speed data transfer network that provides access to consolidated block-level storage. An SAN makes a network of storage devices accessible to multiple servers. SAN devices appear to servers as attached drives, eliminating traditional network bottlenecks.

SANs are sometimes also referred to (albeit redundantly) as SAN storage, SAN network, network SAN, etc.

Techopedia Explains Storage Area Network (SAN)

Introduced in the early 2000s, SANs were initially limited to enterprise class computing. Today, high-speed disk costs have gradually dropped and SANs have become a mainstay for greater organizational storage.

SAN implementation simplifies information life cycle management and plays a critical role in delivering a consistent and secure data transfer infrastructure.

SAN solutions are available as two types:

• Fiber Channel (FC): Storage and servers are connected via a high-speed network of interconnected fiber channel switches. This is used for mission-critical applications where uninterrupted data access is required.
• Internet Small Computer System Interface (iSCSI) Protocol: This infrastructure gives the flexibility of a low-cost IP network.

Both provide advantages based on business requirements.

The advantages of SAN include:

• Storage Virtualization: Server capacity is no longer linked to single storage devices, as large and consolidated storage pools are now available for software applications.
• High-Speed Disk Technologies: An example is FC, which offers data retrieval speeds that exceed 5 Gbps. Storage-to-storage data transfer is also available via direct data transmission from the source to the target device with minimal or no server intervention.
• Centralized Backup: Servers view stored data on local disks, rather than multiple disk and server connections. Advanced backup features, such as block level and incremental backups, streamline IT system administrator responsibilities.
• Dynamic Failover Protection: Provides continuous network operation, even if a server fails or goes offline for maintenance, which enables built-in redundancy and automatic traffic rerouting.

SAN is offered by server manufacturers, such as IBM and HP. Server-independent SAN providers include EMC and Network Appliance.