The private cloud initially promised the same scalability, elasticity, and manageability as public clouds, but with the security and control over on-premise data center environments not possible with the public cloud. The promise seemed unjustified for many years. The fact of the matter was that rather than being the best of both worlds, private clouds were private or clouds at all. Many “private” clouds ran in public cloud environments (making them not “private”), or they failed to deliver any cloud benefits.
The landscape has shifted these days. Private clouds have become the prime part of a hybrid IT or a multi-cloud environment that offers a mix of public and private clouds as well as on-premises virtualized and legacy environments. The question is, do the current private clouds deserve respect, or are they simply another version of earlier vendor cloud washing?
Early Private Clouds Fall Short
The National Institute of Standards and Technology (NIST) formulated the basic definitions of cloud computing in 2011, including the definition of private cloud. “Private cloud: the cloud infrastructure is provisioned for exclusive use by a single organization comprising multiple consumers (e.g., business units).”
Private clouds can be owned, managed, and operated by a private enterprise, a third party, or any combination of third-party providers and private enterprises.
Private clouds can run on or off-premises. In the beginning, when the private cloud was new and just emerging, the goal was an on-premise private cloud to bring the benefits of the public cloud to the corporate data center.
A lot of cloud vendors jumped on the bandwagon, establishing various ‘cloud in a box’ offerings that touted they met the requirements for a private cloud. These offerings were met with limited success because getting the private cloud right turned out to be harder than anyone ever imagined. These early private clouds could not deliver the scalability, elasticity, and resilience of the public cloud.
These hybrid cloud solutions have matured over time. The private cloud leverages the benefits of the public cloud, including rapid deployment, scalability, ease of use, and elasticity. Still, it can also offer additional capabilities including greater control, increased performance, predictable cost, tighter security and flexible management options.”
Public cloud providers stepped up to play the private cloud game. Virtual private clouds were an early offering. “Virtual private cloud is an on-demand configurable pool of shared computing resources allocated within a public cloud environment. It provides a certain level of isolation between different organizations using the resources.”
Virtual private clouds finally delivered on the cloud characteristics that enterprises desired, but they were only ‘private’ because their network settings were logically behind the corporate firewall. Virtual private cloud resources, however, shared data centers, racks, and even servers with third-party cloud resources outside the private.
The Hybrid IT Future of Private Cloud
Private clouds still retain their identity as a separate offering from the public cloud, but they are more likely to be one part of a broader hybrid IT strategy. One of the primary reasons driving the hybrid IT strategy is the recognition that public clouds can’t meet all of the needs of an enterprise. In fact, the records show that there is almost no movement of large enterprise companies that have put their major systems of record (legacy systems) into AWS, Azure, or any other public cloud. There is a growing desire and realization that there is a greater benefit in creating the cloud near where the data is processed than to move it to the cloud. The development of containers and Kubernetes also impacts the role private clouds play within enterprise hybrid IT strategies. The move is toward increasing Kubernetes support for private clouds and even multi-clouds because many private clouds are based on containers.
In the end, any discussion about private and public clouds boils down to a discussion about the hybrid IT cloud. And even then, the discussion is really more about implementation options rather than a strategic decision. It is about the application and the outcome and the best ways to take advantage of modern systems.