Private vs. Public vs. Hybrid Cloud - When to choose what?

Today, it's fair to say that almost all organizations have either moved or are planning a move to the cloud owing to the operational flexibility it offers. Statistics prove as much — consider these as a sample. According to the '2016 State of the Cloud Report' by RightScale, in 2016, the Private Cloud adoption rate stands at 77%, up from 63% in 2015. Hybrid cloud adoption rates increased to 71% in 2016 from 58% year on year, and Enterprise Cloud adoption increased to 31% from 13% in 2015.

Gartner estimates that the global public cloud market is expected to grow approximately 18% in 2017 to a tick over to USD$246.8 billion. Further, almost 74% of tech CFO's credit cloud computing for delivering the most measurable impact on their business this year. Given the wide scale adoption, over the years we have witnessed three main cloud models appear — private, public and hybrid clouds. However, the question remains, which one is the most suitable for your enterprise? In this blog, we take a look at these three models and assess when to use which one.

The Public Cloud

In the Public Cloud space, Windows Azure, Amazon Cloud Services and Rackspace are big players. Amazon elastic compute cloud (EC2) for example, provides the infrastructure and services over the public internet and are hosted at the cloud vendor's premises. The general public, SMEs or large enterprise groups can leverage this cloud model. Here the infrastructure is owned by the company that provides the cloud services. In a public cloud, the infrastructure and services are provisioned from a remote location hosted at the cloud provider's datacenter and the customer has no control and limited visibility over where the service is hosted. But they can use those services anytime anywhere as needed. In the Public Cloud, the core computing infrastructure is shared among several organizations. That said, each organization's data, applications, and infrastructure are separated and can only be accessed by the authorized personnel.

The Public Cloud offers advantages such as low cost of ownership, automated deployments, scalability and also reliability. The Public Cloud is well suited for the following:

• Data storage
• Data Archival
• Application Hosting
• Latency intolerant or mission critical web tiers
• On demand hosting for microsite and application.
• Auto-scaling environment for large applications.

The Private Cloud

A Private Cloud, as the name suggests, is a cloud infrastructure that is meant for use exclusively by a single organization. The cloud is then owned, managed and operated exclusively by the organization or by a third-party vendor or both together. In this cloud model, the infrastructure is provisioned on the organization premise but may be hosted in a third-party data center. However, in most cases a Private Cloud infrastructure is implemented and hosted in an on-premise data center using a virtualization layer. Private cloud environments offer greater configurability support to any application and even support those legacy applications that suffer from performance issues in Public Clouds.

While the Private Cloud offers the greatest level of control and security, it does demand that the organization purchase and maintain all the infrastructure and acquire and retain the skill to do so. This makes the Private Cloud significantly more expensive and a not-so-viable option for small or mid-sized organizations.

Choosing a Private Cloud makes sense for:

• Organization that demand strict security, latency, regulatory and data privacy levels.
• Organizations that are highly regulated and need data hosted privately and securely.
• Organizations that are large enough to support the costs that go into running a next-gen cloud data center.
• Organizations that need high-performance access to a filesystem such as in media companies.
• Hosting applications that have predictable usage patterns and demand low storage costs.
• Organizations that demand greater adaptability, configurability, and flexibility.
• Hosting business critical data and applications.

The Hybrid Cloud

So, what does an organization do when it wants to leverage the cloud both for its efficiency and cost saving but also wants security, privacy, and control? It looks at the Hybrid Cloud which almost serves as a mid-way point between Public and Private Cloud. The Hybrid Cloud uses a combination of at least one Private and one Public Cloud. The Private Cloud can be on-premise or even a virtual private cloud located outside the organization's data center. A Hybrid Cloud can also consist of multiple Private and Public Clouds and may use many active servers, physical or virtualized, which are not a part of the Private Cloud. With the Hybrid Cloud, organizations can keep each business aspect in the most efficient cloud format possible. However, with the Hybrid Cloud, organizations have to manage multiple security platforms and aspects and also ensure that all the cloud properties can communicate seamlessly with one another.

A Hybrid Cloud is best suited for:

• Large organizations that want the flexibility and scalability as offered by the public cloud.
• Organizations that offer services for vertical markets- customer interactions can be hosted in the Public Cloud while company data can be hosted in the Private Cloud.
• Organizations that demand greater operational flexibility and scalability. For them, mission critical data can be hosted on the Private Cloud and application development and testing can take place in the Public Cloud.

Given today's' dynamic and increasingly complex business environment, organizations have to constantly reevaluate their cloud infrastructure, whether Public, Private or Hybrid, to ensure that the cloud delivers on its promise. Since there are different security and management demands for each of these cloud models, organizations have to ensure that they select their application candidates for the cloud wisely so that they can foster innovation and improve agility by leveraging their IT resources optimally. What would your choice be?