As I talk with customers about their interest in and usage of cloud technologies, I am increasingly struck by a strong sense of déjà vu from my time at the forefront of driving the virtualization revolution at VMware. Virtualization was clearly the seed that created the cloud revolution. It’s where everything started. But virtualization is not the same thing as cloud; cloud has evolved significantly. However, there are some strong similarities in their respective business drivers.
Virtualization was initially about running multiple workloads on the same server while isolated from each other in order to safely utilize excess capacity. vSphere then broadened to clusters of servers and abstracted the compute and memory resources across the data center and pooled them together, so that these resources could be better optimized across the workloads. This capability delivered great and quantifiable cost savings in your infrastructure. It enabled IT to run the workloads on many fewer servers, so you could have fewer servers to buy, fewer servers to manage, fewer servers to power. That was all well and good but as time marched on, these cost savings were increasingly taken for granted and it was really the operational benefits that drove the pervasiveness of virtualization. Rapid provisioning and automation, high availability and clustering as an infrastructure feature, DR as a service, vMotion and live migration eliminating the need for planned downtime to name a few. These business agility features along with software control and management, became the fundamental driver of virtualization ubiquity. But at the same time, virtualization also created new challenges, such as VM sprawl for example. Since it was so easy to provision new virtual servers, customers lost track of them and resources were consumed when they were no longer needed.
Virtualization then begot what’s now referred to as the Software-Defined Data Center (SDDC) which meant virtualize and pool all the resources adding network, storage and security to the mix. Virtualize all of these resources, make them software-controlled, and pool them together into an aggregate that can be dynamically apportioned out to workloads, and managed through software not through hardware. Hyper-Converged Infrastructure is a variant of SDDC that takes an integrated packaging approach to SDDC. This comprehensive, programmable, software-controlled infrastructure is what enabled the cloud revolution. And with public cloud, you don’t actually need to own any of these now amorphous hardware resources to run a software controlled data center.
That brings us to cloud today and the explosion pioneered by Amazon. Like virtualization before it, the initial attraction was cost savings. Why buy hardware at all as a fixed capex cost if I can treat it as an on demand operational cost? Only pay for what you use at a fine grained level. These cost savings are ephemeral though, they eventually get taken for granted in the base line.
Which brings us to the operational benefits inherent in cloud computing. In addition to all of the earlier operational and management benefits of SDDC, cloud also offloads all hardware and much of the software maintenance to service providers. How does public cloud differ from software defined data center? I think there are several fundamental differences. The value of the cloud is not just about moving workloads to hardware that you no longer own. It also embraces higher levels of abstraction, software as a service (SaaS); business services being offered directly from the cloud to end users. IT is no longer running the application or service, nor are they hosting it, nor are they managing it running in the cloud. You’re simply paying for a service and using it. That’s what SaaS is all about and I believe it will become the dominant model for business services and applications that don’t provide competitive differentiation. For workloads that do provide competitive differentiation or are a core service that a business is delivering, another important offshoot of cloud is what’s referred to as PaaS or platform as a service. This is application middleware that exists in the cloud that so-called Cloud Native or modern scale-out applications are built on. Clouds are expected to deliver those as well and they are fundamental to delivering agile applications and services designed for the mobile/cloud era. So the first big difference is the design center – the software defined data center is about IaaS or Infrastructure as a Service still managed by the enterprise while the public cloud is about higher levels of abstraction and application delivery.
Another big difference between Software-Defined Data Center and public or hybrid clouds is elasticity; being able to grow and shrink workloads, supply resources on demand rapidly in order to cost effectively handle peaks and lulls in demand for your applications. SDDC can enable elasticity also, but what it doesn’t have is usage-based pricing. With an SDDC, you still need to own enough hardware to handle simultaneous peak-workload demands. Public or hybrid cloud brings the ability to handle burst capacity when needed; pay for what you’re using when you need it and don’t pay for what you’re not using as a “just in case” expense. That also illustrates how a cloud is much more than virtualization. These capabilities I am describing are business agility for the cloud era, a similar sustainable driver for cloud value, just as it was for the virtualization era. But to achieve the theoretical operational benefits and agility of virtualization, SDDC and cloud, one still needs a comprehensive, cloud management and automation platform.
I would be remiss if I didn’t point out another important similarity. Cloud suffers from largely the same VM sprawl problems as virtualization did! It’s so easy to provision new VMs that they’re easy to lose track of. Except in the public cloud, it’s actually a worse problem because they now cost real money!
So cloud, like virtualization before it, started with cost savings and ended up at business agility as its primary sustainable business benefit.