What is Hybrid Cloud?

The hybrid cloud is the combination of a public cloud provider (such as Amazon Web Services, Google Cloud,...) with a private cloud platform one that's designed for use by a single organization. The public and private cloud infrastructures, which operate independently of each other, communicate over an encrypted connection, using technology that allows for the portability of data and applications.

A hybrid cloud is an integrated cloud service utilising both private and public clouds to perform distinct functions within the same organisation. All cloud computing services should offer certain efficiencies to differing degrees but public cloud services are likely to be more cost efficient and scalable than private clouds. Therefore, an organisation can maximise their efficiencies by employing public cloud services for all non-sensitive operations, only relying on a private cloud where they require it and ensuring that all of their platforms are seamlessly integrated.

Hybrid cloud models can be implemented in a number of ways:

  • Separate cloud providers team up to provide both private and public services as an integrated service
  • Individual cloud providers offer a complete hybrid package
  • Organisations who manage their private clouds themselves sign up to a public cloud service which they then integrate into their infrastructure

In practice, an enterprise could implement hybrid cloud hosting to host their e-commerce website within a private cloud, where it is secure and scalable, but their brochure site in a public cloud, where it is more cost effective (and security is less of a concern). Alternatively, an Infrastructure as a Service (IaaS) offering, for example, could follow the hybrid cloud model and provide a financial business with storage for client data within a private cloud, but then allow collaboration on project planning documents in the public cloud - where they can be accessed by multiple users from any convenient location.

A hybrid cloud configuration, such as hybrid hosting, can offer its users the following features:

  • Scalability: whilst private clouds do offer a certain level of scalability depending on their configurations (whether they are hosted internally or externally for example), public cloud services will offer scalability with fewer boundaries because resource is pulled from the larger cloud infrastructure. By moving as many non-sensitive functions as possible to the public cloud it allows an organisation to benefit from public cloud scalability whilst reducing the demands on a private cloud.
  • Cost efficiencies: again public clouds are likely to offer more significant economies of scale (such as centralised management), and so greater cost efficiencies, than private clouds. Hybrid clouds therefore allow organisations to access these savings for as many business functions as possible whilst still keeping sensitive operations secure.
  • Security: the private cloud element of the hybrid cloud model not only provides the security where it is needed for sensitive operations but can also satisfy regulatory requirements for data handling and storage where it is applicable
  • Flexibility: the availability of both secure resource and scalable cost effective public resource can provide organisations with more opportunities to explore different operational avenues.

One clear benefit of a hybrid cloud model is having on-premises, private infrastructure that's directly accessible in other words, not being pushed through the public internet. This greatly reduces access time and latency in comparison to public cloud services. With the looming risk of the consolidation of ISPs at the consumer/business level in the United States, the current halting of Net Neutrality, and the volleying of threats between ISPs and service providers, reliance on the proper functioning of the internet a single point of failure that can bring down the normal operations of an entire company is an unacceptably high risk.

Another benefit of a hybrid cloud model is the ability to have on-premises computational infrastructure that can support the average workload for your business, while retaining the ability to leverage the public cloud for failover circumstances in which the workload exceeds the computational power of the private cloud component.

This provides the added benefit of paying for the extra compute time only when these resources are needed. Accordingly, for businesses that have milestones throughout the year where a much higher than normal amount of compute time is needed (tax season, perhaps), extending to the public cloud is a cheaper proposition than building out a private infrastructure that sits idle for most of the year.

Building out the private end of a hybrid cloud also allows for flexibility in server designs. This gives companies the flexibility to provision rapid and archival storage at a likely lower cost. Combined with the announcement of new 19nm server-grade SSDs, and the Helium-filled 6TB drives from HGST, data storage fast or slow can be achieved without the use of backup tapes.

Although hybrid cloud provides a variety of advantages over the public cloud alone, it still suffers from the same privacy and security issues that plague the popular perception of public cloud platform providers. Allowing information to be transported across a network that can be subject to third-party interference or tapping is, to many organizations, an unnecessary and reckless security risk.

In addition, hybrid cloud as well as public cloud is a poor fit for circumstances in which data transport on both ends of the cloud is a mission-critical operation that is sensitive to the delay from transporting data across a network and the latency in ping times. For example, Tatsuya Kimura, the head of international affairs at the Japan Meteorological Agency (JMA), has questioned the ability to offload weather prediction data to the cloud.

Currently, the JMA supercomputer is an 847-teraflop system designed by Hitachi. This supercomputer helps the meteorologists determine whether a tsunami warning should be issued following an earthquake. It's also used to predict earthquakes in the Tōkai region, where the tectonic movement is particularly well understood. As these predictions are intensely time-critical, attempting to offload this computational workload to the cloud is not feasible.

Then there's the issue of money. Organizations that have a thin IT budget probably can't afford a rollout of a hybrid cloud solution. The upfront cost of the servers on the private end of the spectrum is as one might expect of racks of server hardware a substantial one, and the needs of smaller businesses likely to have small IT budgets can likely be served adequately using the services of a public cloud provider.

Hybrid clouds are frequently deployed in the financial sector, particularly when proximity is important and physical space is at a premium such as on or adjacent to a trading floor. Pushing trade orders through the private cloud infrastructure and running analytics on trades from the public cloud infrastructure greatly decreases the amount of physical space needed for the latency-sensitive task of making trade orders. This is crucial for data security, as well. Threshold-defined trading algorithms are the entire business of many investment firms. Trusting this data to a public cloud provider is, to most firms, an unnecessary risk that could expose the entire underpinnings of their business.

Hybrid cloud technology is also widely used in the healthcare industry, as the need to relay data between healthcare providers and insurance companies for hundreds of thousands of patients is a daunting task. Compliance with HIPAA (the Health Insurance Portability and Accountability Act) in this regard is a regulatory hurdle, since compartmentalizing information to comply with HIPAA over not disclosing protected health information requires extensive permissions settings.

For similar reasons, law firms utilize hybrid cloud infrastructures, often as encrypted offsite data stores, to safeguard against the potential for loss due to theft, hardware failure, or a natural disaster such as a hurricane destroying the original documentation or evidence.

Retail sales is another industry that makes use of hybrid cloud services. Transporting sales information, and the analytics derived from that data, is a computationally intensive task. According to Bryan Cantrill, the CTO of Joyent, many retail firms are avoiding public cloud offerings from Amazon and Google.

Amazon, being the largest competitor to most (if not all) retailers, is seen as untrustworthy from their vantage point. And not all retailers want to share their sales analysis data with Google, which holds a majority of the search engine market in most of the world, combined with its extensive presence in advertising.

Using a hybrid cloud can greatly facilitate connectivity in the workplace. In addition to managing files, companies must integrate with various business processes, such as internal messaging, scheduling, business intelligence and analytics, and other CRM systems. Public cloud offerings alone do not readily (if at all) integrate with on-premises hardware. Devices such as printers, scanners, fax machines, and physical security hardware, like security cameras, fire, and CO₂ detectors, can be encumbrances to public cloud adoption. Rather than isolate these mission-critical devices from the rest of the organization's network, using a private cloud component would be far more efficient.

With the hybrid cloud model, IT decision makers have more control over both the private and public components than using a prepackaged public cloud platform, especially for enterprise content management. These prepackaged software-as-a-service (SaaS) solutions face frequent redesigns and edits without prior notice or consent and, if poorly written, can break compatibility with pre-existing content.