As cloud computing gains mainstream adoption, vendors are jostling for position to gain ownership over the "true meaning of cloud." The definitional battleground is important evidence that cloud, and software as a service (SaaS), are maturing.
Following a discussion among the Enterprise Irregulars, top analyst, Phil Wainewright, took up the charge and wrote a post to bring clarity to the definition issue. Phil identifies four key elements of true cloud computing:
Abstracted infrastructure. In most cases, that means virtualization, but I’ve chosen a slightly more generic term because virtualization implies a specific technology choice and the key point here is that the underlying infrastructure isn’t tied to any specific hardware or operating software. In theory, any component could be swapped out or exchanged without affecting the operation of whatever is running above.
As-a-service infrastructure. The pairing of virtualization with automated provisioning and management has been a crucial element in enabling the on-demand, pay-as-you-go nature of public cloud.... But these components alone are not the only constituents of cloud. Taking existing platforms and applications and implementing them on a pay-as-you-go, virtual machine is not cloud computing. You’ll still have enormous extra management overhead, duplicated resources and wasted redundant capacity — and gain none of the additional benefits of a fully cloud-scale environment.
Multi-tenancy. Sharing a single, pooled, operational instance of the entire top-to-bottom infrastructure is more than simply a vendor convenience; it’s the only way to really achieve cloud scale. Look beyond the individual application or service and consider also the surrounding as-a-service infrastructure and any connecting framework to other cloud resources. Understand the value of having all of that infrastructure constantly tuned and refreshed to keep pace with the demands of its diverse user base across hundreds or even thousands of tenants.... Every tweak and enhancement is instantly available to every tenant as soon as it’s live.
Cloud scale. It’s no accident that cloud architectures are multi-tenant — just look at Google, Amazon, Facebook and all the rest. If you start from a need to perform at cloud scale, you build a multi-tenant infrastructure. It’s the only way to deliver the walk-up, on-demand, elastic scalability of the cloud with the 24×7 reliability and performance that the environment demands. Cloud scale consists of all of this globally connected operational capacity, coupled with the bandwidth and open APIs required to effortlessly interact with other resources and opportunities and platforms as they become available in the global public cloud.
Advice for enterprise buyers. Phil's points offer a reasonable starting place for understanding the unique attributes that constitute cloud computing. As the vendor landscape around cloud becomes more crowded, expect to see greater proliferation of tactics based on spreading fear, uncertainty, and doubt (FUD); it's a sure sign that the market for cloud solutions is growing.
To cut through the clutter of confusing and contradictory marketing messages, use Phil's list to help evaluate prospective cloud vendors.
Just for for fun, take a look at this video from cloud ERP vendor, NetSuite. The video is cute, but really does show alignment with Phil's list.