The current crop of cloud storage solutions have many important differences from traditional SAN and NAS storage. This post by Nirvanix explains the difference between SAN-NAS storage and cloud storage, by first setting out what traditional storage is:
“Most IT infrastructures contain a wide variety of storage devices, but these have traditionally been divided into two categories:
Primary or production storage serves active applications and is accessed randomly. The primary category includes most familiar direct-attached disks (DAS), storage area networks (SAN), and network-attached storage (NAS). Newcomers in the primary category include content-addressable storage (CAS) and cloud storage services, including the Nirvanix Cloud Storage Service.
Secondary storage is used for data protection and is normally accessed sequentially. Tape media and optical discs were the traditional secondary storage types, but disk-based systems including virtual tape libraries (VTL) have recently become popular. CAS and cloud systems are also often used for secondary storage due to their lower cost.
The performance and capability of primary storage systems varies greatly, as does the price. For this reason, many large organizations classify their primary storage into a number of tiers. Tier 1 storage typically boasts the highest performance, reliability, and cost. Fibre Channel SAN arrays from companies like EMC, HDS, and IBM have dominated this market for over a decade. Most organizations also offer less expensive lower-tier SAN, NAS, and DAS capacity in an effort to reduce their capital equipment cost.
The difference between NAS-SAN and Cloud Storage is:
- Cloud storage was developed independently from all historical storage concepts
- Cloud storage also leverages the openness of the Internet
- Many interface solutions have been developed to bridge traditional storage protocols to the cloud
- the real benefit from cloud storage comes when applications take advantage of its compelling distribution, collaboration, and programmability capabilities.
Read the whole post here.
