A private cloud is a cloud deployment model where a single organization owns and administers its own cloud and the underpinning networking infrastructure to support it. This model creates central access to IT resources for departments and staff across multiple locations and potential regions. Private clouds are implemented behind the organization’s firewall which is the major distinguishing factor from other cloud deployments models. In the private cloud model, the organization that owns the private cloud is both cloud consumer and cloud service provider (CSP).
Because private clouds rely on internal resources, companies primarily choose the model so they retain security and control over their network. Recouping recurring costs from public CSPs is another major motivator for operating a private cloud. However, service level agreements (SLA) agreed to when companies use CSPs can also help keep costs down by shifting operational risk to the CSP and holding them to a particular quality of service (QoS).
Adopting a private cloud strategy demands that companies consider the worth of the network based on its business use, the necessity of private resources, and the cost of maintaining the network and supporting infrastructure, versus alternatives such as virtual private clouds (VPC), that enable private clouds in a public cloud space.
Private clouds are operated behind a single owner's firewall, because of this, they are referred to as single-tenant environments with isolated access to resources. Compared to public CSP, private cloud infrastructure is usually hosted on-premises in the owner’s data center. Alternatively, the company can rent infrastructure from an IaaS vendor placing their infrastructure offsite but still under company control. In either case, virtualization is the key technology that enables both private and public clouds.
Virtualization uses various technologies to abstract the physical infrastructure from the mind of the user—in the end, cloud consumers will see only the cloud and its capability to host a seemingly infinite amount of data and services. Underneath, virtualization turns compute resources into a centralized, sharable pool of resources that an organization can allocate to its business units on demand, while still maintaining control of resources and applications.
Cloud management platforms offer IT administrators visibility that assists them in controlling and extending the private cloud resources. Integrations with cloud infrastructure monitoring software and infrastructure automation software extend these management platform capabilities for private clouds in much the same way that public CSPs. By monitoring and automating many tasks CSP adds easy capacity scaling while reducing human error.
While each cloud architecture is specific to the organizational owner, cloud provisioning technology is similar across all cloud types—private, public, hybrid, multicloud. These provisioning technologies enable the pooling of resources and the creation of virtual machines to emulate many computing environments on limited infrastructure. For private clouds, provisioning is performed behind the company firewall, for the use of the company only. The three key cloud-enabling technologies in private cloud architectures are:
1. Virtualization — Virtualization is key to cloud computing. By abstracting how cloud consumers utilize IT resources, the underpinning IT infrastructure can be managed separately. This means that multiple virtual environments can coexist on the same hardware—virtual machines are these virtual environments, interacting with hardware through the assistance of a coordinator called the hypervisor. Abstraction allows CSPs to dole out resources in pieces rather than chunks to fit many use cases (purchasing an entire server is not necessary when you can rent a portion of it), they can adjust pricing based on usage, and they can extend and scale services on-demand at the request of the cloud consumer or automatically in peak times.
2. Cloud Management Software — Cloud management software centralizes cloud monitoring and controls over network infrastructure and applications running on private clouds. These toolsets feature controls for many cloud-related functions: monitoring, orchestration, optimization, costs, and security. More sophisticated cloud management platforms (CMPs) are used to help companies manage two or more dynamic cloud environments, any combination of private, public, hybrid, or multicloud.
3. Cloud Automation Software — Cloud management is filled with complex processes with significant minutiae that are prone to human errors, and cause lag on business processes when tasks must be performed manually. For these reasons, many cloud-dependent organizations turn to automation to relieve themselves of these burdens. In reality, many cloud tasks can and should be automated, especially as the number of cloud consumers grows which makes automation the only viable solution for efficiency gains.
In a private cloud deployment model, ownership of the cloud is the primary benefit for companies. Ownership guarantees companies complete control over configuration and access to IT resources in the most effective and efficient deployment for their needs. They can customize based on staff, departments, and regional locations. Private cloud solutions are usually implemented behind the corporate firewall allowing the following benefits.
While not a guarantee, owning and operating private clouds tend to cost more than other public cloud options. For small and medium businesses, public clouds often prove to be strategically better choices since much of the IT responsibilities are offloaded onto the CSP, effectively reducing the cloud consumer’s IT department to a budget line item.
A virtual private cloud (VPC) is a “cloud within a cloud” configuration where an organization establishes a private virtual networking environment within a cloud service provider’s public cloud. This “private cloud in the public cloud” usually grants complete control over the private virtual space, security, and where resources are located depending on availability by the CSP. The major benefit of the VPC deployment is to offload infrastructure risk onto a CSP, with many subsequent benefits like reduced IT staff, and associated infrastructure and staffing costs, and future-proofing the organization's tech stack.
There are similar concepts that sometimes are crossed with VPCs, such as virtual private servers, and virtual private networks. Virtual private clouds are very similar to virtual private servers (VPS) but with significant differences. A VPS, like a VPC, exists in the cloud, but uses only a fixed portion of the server with fixed resources—when accessing VPS, users can interface with it as if it were a local drive. A VPS lacks efficient scalability, which distinguishes it from other virtual cloud models. A VPC, contrastingly, is not bound by the underlying infrastructure, but rather their architecture allows them to scale on-demand.
VPNs are not a server technology. Virtual private networks (VPNs) allows users to securely access a company's intranet from outside the firewall, and can be said to make a secure line over a public network like the Internet. Likewise, a worker can use a VPN connection to securely connect to a company’s VPC from anywhere they can access the Internet. VPNs are used to secure connections and transmit and receive data privately.
Private cloud management best practices develop a foundation of sustainability. The following practices create shared understanding and central thinking that reduces management burden.
Enterprises and organizations have a plethora of private cloud solutions to choose from. When considering options, there are some general categories of solutions to be aware of.