Private vs public vs hybrid Cloud: The pros and cons

cloud computing types

The cloud has taken the world of computing by storm, and experts predict that more than 50% of IT will be in the cloud within the next five to ten years.  However, enterprises still need to get their cloud approach and strategy right if they hope to realize the many benefits that the cloud offers.  Among the first considerations for any enterprise is whether to deploy their data in a public cloud, private cloud, or hybrid cloud.

Public cloud

The public cloud is the basic cloud model, where a third-party provider offers shared and scalable resources, such as applications and storage servers, which users may access over the Internet.  Many laaS providers, such as Amazon Web Services, offer pay-per-usage models to which anyone can subscribe.

The public cloud offers many advantages.  It is the most straightforward and simple, among various cloud deployment, option that offers enterprises the convenience to sign up and set up their required infrastructure with considerable ease in double-quick time.  It is very easy to use as well, and generally operates at very fast speeds.  An added advantage is the ease to add or shed capacity as required, allowing for unbridled flexibility.

Another significant advantage of the public cloud is its cost-effective pay-per-use model.  Most cloud providers offer elastic pay-as-you-go offerings, allowing users to pay only for the resources they actually use, and for the time they use it.  Some basic services are even available for free. With publiccloud, enterprises may shift capital expenditure on IT resources to operational expenditure that can then be better appropriated and passed on accurately to end customers. The public cloud shifts hassles of administration and maintenance to a third-party service provider. Businesses who subscribe to publiccloud infrastructure share resources with other users who have done likewise.

The public cloud also makes it possible for users to access their resources from just about anywhere on the globe, across any device; the only requirement being right credentials and an Internet connection.

However, for all the benefits, the public cloud does also have its shortcomings. Issues like unreliability or outrages at the cloud server end, where nothing can be done but wait because of third-party control and administration, remain huge.  Variable broadband Internet connections could cut data off entirely and leaving access to the cloud also undependable.

Security and legal issues remain the main concern, however, with the public cloud and its shared resources and transactions over the Internet.  Susceptible to online hacking as well, the issue of data sovereignty as well is cause for apprehension with data centers outside the country of actual business.

The Private Cloud

Private cloud is essentially a cloud computing platform set up within the corporate firewall, tailored to the specific needs of the enterprise.  Third-party providers may have a role in running and managing the platform, but it remains under the operational control of the enterprise.

The private cloud is an attempt to address two significant limitations of the pubic cloud, control and sovereignty of data, and address these issues reasonably well. This is a customized set up, specific to the enterprise, and the enterprise can decide who has access to the data and where exactly to store the data.  The data may be stored in-house or at any specific third-party data center selected by the enterprise.  Either way, it offers greater control and reliability compared to public clouds.

While the private cloud loses out on easy scalability, it makes up with ease of customization.  It becomes very easy to customize storage and networking components so that the cloud becomes a perfect fit for specific organizational requirements. The private cloud model allows enterprises to customize the cloud configuration and architecture as per requirement, even while leveraging secure third-party help for maintenance.  Logistically, it is simpler to migrate from an on-premises application to a private cloud than a public cloud.

However, these benefits obviously come at a greater cost compared to public clouds.  Also, private clouds being managed onsite would cost the enterprise time, money, workforce and other resources. This can quickly get out of control and negate the very advantage that the cloud offers in the first place.  Again, the talk of private clouds being intrinsically more secure than public clouds holds true only in theory.  There is nothing to prevent an enterprising and determined hacker to breach a private cloud, just as they breach even the most secure networks in the world time and time again.

All this considered, the private cloud is a good option for enterprises that handle sensitive data and have to comply with many regulations, or for enterprises concerned about the theft of their intellectual property.  The popularity of private clouds is growing, as IDC estimates 69% of manufacturers worldwide now have more than two applications in a private cloud.  Managed private clouds are expected to grow by 45% in 2015.

The Hybrid Cloud

The hybrid cloud is a “mix and match” approach, where the enterprise picks and chooses various elements from either the public cloud or private cloud.  It is a radical approach, trying to build a cloud model that suits a specific application best, rather than trying to fit it all on just one cloud model.

The hybrid cloud works well for enterprises that are capable of splitting their data into “sensitive” and “non sensitive” spheres, and big data.  For instance, the enterprise could host its ecommerce website data that includes customer credit card details on a private cloud and host non-sensitive data such as marketing data and training resources on the public cloud.  Enterprises could also use this approach to handle seasonal spikes of data effectively – for instance they could have a secure private cloud in place, and take up extra space on the public cloud on a temporary basis, to cater to the seasonal spike of data.

Hybrid clouds in a sense offer the best of both worlds – the convenience and scalability of public clouds and the security and control of private clouds.  It is flexible as well, with enterprises free to use as many public cloud resources as required, or even alternate between public clouds and private clouds.  The model is overall more efficient since much of the cost effectiveness that the public cloud offers is retained.

However, hybrid cloud environments are only as strong as the integrations that unite them.  It requires a considerable amount of performance monitoring, regular testing, and data ingress and egress procedures to manage the disparate infrastructure to ensure business processes take place seamlessly.  All this obviously also means extra work and, by extension, more costs.

The hybrid cloud is nevertheless the fastest growing cloud model compared to other models.  About 82% of enterprises now adopt a multi-cloud strategy, while only 10% use a single public cloud and another 5% use a single private cloud. Among those enterprises who adopt a multi-cloud strategy, 14% of enterprises use multiple private clouds, 13% use multiple public clouds, and 55% use hybrid clouds.

All things considered, there is no one-size-fits-all solution.  Public cloud, private cloud and hybrid cloud, each come with its own share of advantages and disadvantages, and all these have their relevance. The best approach depends on the specific nature of the business.

Author : Nayab Naseer Date : 29 Jun 2015