Storing information in the public cloud from a growing market of vendors is a viable alternative to on-premise, traditional storage options for some use cases, research firm Gartner says.

But cloud-based storage providers vary widely in their ability to meet the requirements of enterprise IT, which is why customers should rigorously plan and vet vendors before first engaging in a pilot and then deciding if mission-critical data should be moved into the cloud-based storage service.

The benefits of cloud-based storage are similar to those offered by other forms of cloud computing: It can provide significant cost and agility benefits to end user customers. Concerns around security, privacy and accessibility - which are common concerns for other cloud use cases as well - also exist in the cloud storage market, however.

The vendor landscape in the cloud storage market is budding. Big-name traditional storage vendors - Microsoft and IBM - are competing with up and coming all-cloud companies like Amazon Web Services and Nirvanix, while other companies are migrating from managed hosting into a set of cloud storage offerings. Initial vendors will compete on pricing, security and resiliency, Gartner says, while "forward-looking" providers differentiate on service reliability, support, ease of management, turnkey deployments and integrated value-add services.

Watch out for hidden costs too, Gartner warns. Consider the total cost of ownership, which goes beyond just the per-GB storage rate, but also includes bandwidth, data access costs, migration fees and both internal and external support requirements. The generic, pay-as-you-go model that all these providers use is a fundamentally different sales and support model compared to traditional on-premise storage deployments. But, vendors offer APIs for data access and automatic scalability meant to meet all the demands of customers, no matter the size of data they store.