Data centers use technical terms to describe the various routes of data and storage. Each storage solution has different benefits and tradeoffs to fit different storage needs. When considering which route is best for your storage needs, there are several questions to consider.
How much storage capacity will you need? Will you be able to add additional storage on-demand? How much data availability are you going to need?
Direct Attached Storage (One-to-One): DAS is adding an external storage device to an existing server or PC to extend storage capacity. DAS is suited for newer small businesses with limited storage needs. Examples of this type of storage are portable USBs, thumb drives, zip drives and the PC external hard drive.
Network Attached Storage (One-to-Many): NAS makes stored data and files available to multiple users in multiple locations, using different operating systems. NAS servers utilize file level transfers, while DAS and SAN block level transfers. Example of this type of storage are file servers, email archiving and storing media files for web apps.
Storage Area Networks (Any-to-Any): SAN makes all storage devices available to any server on the network. Most businesses use SAN for over half of their storage needs. SANs are more complex to manage, but the ability to share the storage on multiple servers allows you to configure storage capacity as needed. Examples of this type of storage are entry-level virtualization, supporting interrelated resources, databases and centralizing enterprise storage.
Cloud (Masses-to-Masses): Cloud is pooled server resources that house massive data stores in remote data centers able to scale on-demand. Examples of this type of storage are serving rich media files, content delivery networks and web hosting. The major differences between all four of the storage solutions are cost, whether storage is shared or dedicated and whether additional storage can be added on-demand.