Cloud computing: private, public or both?

Kyle MacDonald

on 14 November 2012

This article was last updated 9 years ago.


This article was published in Virtual Strategy magazine earlier this month. We think you’ll like it, so here it is.

“A growing number of organisations worldwide are seeing the value of cloud computing as a way of increasing IT flexibility and lowering in-house infrastructure costs. However, achieving the right blend of security, control and cost efficiency depends on choosing the right public or private infrastructure – or the right balance of both,”

Cloud computing is in the ascendancy, with companies of all sizes and sectors getting in on the action. Rapid growth in cloud adoption is highlighted by Gartner’s latest quarterly IT spending report, which predicts a 19% growth in cloud investments during 2012 compared to overall IT spending – which will increase just 3%.
The inexorable shift to the cloud is delivering cost and efficiency gains for businesses across all sectors, from reduced in-house infrastructure requirements and costs, to scalable, on-demand access to networks, compute resources and storage.
With such compelling benefits on offer, the issue for many organisations is no longer whether to do cloud computing – but how.

 

The Private Public Cloud Conundrum

As a first step towards deployment, businesses typically choose between public and private cloud infrastructure – a decision that is difficult for some companies to make.
As the name suggests, private clouds reside on company owned servers behind the corporate firewall, providing high levels of control and flexibility. By contrast, public clouds are hosted online, delivering virtually unlimited, on-demand access to a wide variety of IT resources at low cost.
So which one is best?

 

Private Cloud Pros and Cons

Some sectors, such as the financial services and medical industries, require sensitive transactional and customer data to be stored on dedicated servers inside the corporate firewall. If that’s the case in your business, a private cloud is your only option because this personal data can not be compromised.
Even where regulation plays no part, though, many businesses consider private clouds to be more secure than online, multi-tenancy environments as critical systems and data remain inside the business at all times. For this reason, private clouds are often chosen for managing mission-critical applications and data.
Because organisations have full control over private clouds, it’s possible to build in bespoke solutions for fault tolerance, business continuity and disaster recovery. Total control over every aspect of the environment ultimately helps to ensure critical applications and services are always available for staff and customers.
While the benefits of private clouds are clear, there are also some disadvantages to consider. For example, there will always be a capacity ceiling due to the limitations of the physical hardware in the organisation’s own server room. What’s more, many private cloud vendors lock customers in with proprietary software, APIs and standards – increasing costs, forcing unwanted upgrades and limiting access to the latest cloud features being developed globally.

 

Public Cloud Pros and Cons

Where the capacity of in-house infrastructure may be restricted by the capabilities of physical hardware, no limits exist in the public cloud. A range of providers, from Amazon and Rackspace, to Dell and HP give businesses immediate, cost-effective access to online compute and storage resources on demand.
With no need for infrastructure on site, public clouds dramatically reduce hardware and management requirements and costs. What’s more, they support fast deployment of new services and enable scalability on demand.
Public clouds are ideally suited to handling high-volume, routine workloads that present minimal security risks. They also offer a great solution where computing resources are needed on a temporary basis, for example, while developing and testing new applications.
To provide additional flexibility, public clouds allow customers to choose their preferred operating system, reducing the risk of vendor lock-in and functionality limitations. However, some use proprietary APIs, which could reduce the flexibility to move workloads to other cloud providers in the future.
On the downside, public clouds are multi-tenancy environments that are seen as less secure than private clouds. It’s certainly true that customers have no control over the underlying infrastructure, requiring you to place all your trust in the public cloud provider.
Each public cloud provider has its own SLAs for security, backup, disaster recovery and availability. Check these thoroughly before you buy to see exactly what you’re getting from your cloud provider and to make sure they are meeting their performance targets over time.

 

Other Things to Consider

There may be compelling business reasons to choose a public cloud over a private cloud, or vice versa. However, IT requirements change constantly, and you may want to move workloads between different cloud providers in the future to reduce costs or explore new cloud offerings. For this reason, organisations should consider building their cloud infrastructure on open-standards-based, open-source technologies from the ground up.

 

Building an Open Cloud with OpenStack

Originally developed by NASA and Rackspace, OpenStack provides all the infrastructure components needed to build truly open cloud infrastructure. OpenStack is the foundation for many of the leading public clouds – including Rackspace, Amazon, HP and more. By providing the same standard, open APIs to build private clouds, OpenStack eliminates vendor lock-in and allows workloads to be migrated seamlessly between private and public clouds when needed.
Working on top of OpenStack, leading open-source operating systems can be used to spin up virtually unlimited numbers of ‘guest’ server instances at no additional cost. To provide even greater value, the leading open-source operating systems provide tools for fast bare metal provisioning and orchestration, deployment and scaling.

 

Get the Best of Both Private and Public Cloud Worlds

If you still can’t decide whether private or public cloud infrastructure best meets your needs, why not do both? Open technologies give you this option, with tools for creating and managing ‘hybrid’ cloud environments.
In the hybrid cloud world, private cloud infrastructure provides control, regulatory compliance, cost management and security. At the same time, workloads can be sent to the public cloud to increase economic efficiency and burst capacity. With careful planning and the right open environment, it’s possible to scale private cloud infrastructure into public clouds such as Rackspace, Amazon, HP and others.
There are simple ways to control and manage hybrid clouds through integrated dashboards that simplify service deployment and administration, while ensuring compliance with regulations for systems and data management.

 

De-risking the Public/Private Cloud Decision

Organisation’s deciding to deploy proprietary cloud solutions, should be aware of becoming locked in with a specific vendor and upgrade cycle. If this happens, organisations will be limited in their ability to move workloads between clouds seamlessly as processing and storage needs evolve.

By contrast, taking the open route to cloud deployment helps businesses remain agile and take advantage of the latest cloud features. Most importantly, this approach takes the risk out of deployment decisions today, with the possibility of shifting seamlessly between private, public and hybrid clouds in the future.

 

Ubuntu Cloud Infrastructure – the OS for the Open Cloud

Ubuntu is the leading guest OS on public clouds, as well as providing all the tools you need to build and deploy private and hybrid cloud infrastructure.
Ubuntu is optimised at every level to support elastic scaling of IT resources in private, public and hybrid clouds. What’s more, it offers a number of additional innovations that help companies build better clouds, including:

  • Awesome ensures that an organisation’s tools can work with both Amazon Web Services and OpenStack-based clouds, private or public
  • Juju uses ‘charms’ to rapidly deploy and scale particular cloud-based workloads or services across private and public cloud infrastructure
  • MaaS provisions hyperscale deployments of physical servers, bringing cloud-like semantics for on-demand capacity to the physical server provisioning process.
  • Ubuntu Advantage provides enterprise-class support for private, public and hybrid cloud deployments.

 

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