In its most basic form, hybrid cloud is the unification of a private cloud and public cloud deployment such that they operate together seamlessly within an enterprise. The “hybrid” term means the private and public clouds function independently but operate and provide services as a unified IT infrastructure.
A private cloud consists of a well-controlled IT infrastructure where the servers, network, storage, applications, and everything in between are entirely dedicated to an enterprise. Private clouds are usually on premises, but they can be externally hosted. As the “private” connotes, the environment including all resources are used exclusively by the enterprise.
As a cloud platform, private cloud implementations are the most mature, but they are not without their share of challenges:
- Expense – The hardware and supporting physical infrastructure costs significant money, both for the initial purchase (capex) and then for the ongoing running costs.
- Bounded capacity – The computing and storage resources are limited by the physical resources deployed. Once depleted, bringing additional resources on board is slow and time consuming.
- Underutilization – Due to the previous point - over provisioning of computing and storage is common. It is also wasteful and expensive.
- Expertise required – managing a private cloud requires specific expertise in multiple areas including networking hardware, firewalls, and more. Private clouds also may require strategic outsourcing which requires additional expertise and can be expensive.
A public cloud consists of an IT infrastructure that is hosted externally by a third party. The IT resources including compute, storage, and applications are hosted on a platform that hides the intricacies of the IT environment from the user. Public clouds that host applications are able to deliver great value because the platform can be readily optimized to take advantage of an application’s capabilities.
There has always been a healthy bit of skepticism as it applies to the public cloud:
- Security – Can the data be completely secured?
- Compliance – Who has access to customer data? How is it protected?
- Location – Where are the IT resources hosted? Impact to performance and availability?
- Backup/Restore – When and how often?
- Availability – What happens if business critical application goes down?
Advantages of Hybrid Cloud
Hybrid cloud bridges the gap between private and public, delivering the best of both worlds by providing a middle ground. Private cloud allows for more granular control and security, while public cloud delivers scalability and flexible infrastructure costs.
- Scalability – Public cloud infrastructures are inherently large and can scale out computing resources on demand, provisioning based on the amount of resourced need. Private clouds can scale as well, but at a significant cost. Maintaining hardware until needed or purchasing in a short and unplanned time frame is expensive.
- Better Performance – The availability of more computing resources in the public cloud means hosted resource intensive applications will run more quickly. For example, big data analytics is well suited for the public cloud. A retailer may choose to keep certain functions “private” i.e. financials or store inventory, but choose to perform an analysis of customer behavior using the public cloud.
- Security – Users can still leverage the public cloud to run applications against data that is secured in a private cloud. In addition, network and virtualization technology continue to advance with more secure constructs helping to mitigate some of the security angst associated with keeping data in the public cloud.
- Public cloud providers are increasingly offering Points of Presence (PoP), which bypass the internet all together for dedicated network connections between the private and public cloud.
- It can be argued that public cloud infrastructures and accompanying applications are more secure than some private cloud deployments. Successfully securing data is less about where it resides and more about the competency and practices of IT in securing the data and the accompanying IT infrastructure. Public cloud providers are fully cognizant of the ramifications of security breaches and devote time, resources, and especially talent to ensure their services are secure. “Security” is only as good as the technology and the implementation, no matter public, private, or hybrid!
- For enterprises that need the power of the public cloud but seek a higher level of security then “virtual private cloud” (VPC) services are worth a closer look. VPCs are basically private cloud infrastructure provided within public cloud, VPC network traffic is far more secure. VPC provide the security of a private cloud, with the power, flexibility, and elasticity associated with a public cloud.
- Reliability – No cloud model can boast 100% uptime; however, public clouds tend to be more resilient because the underlying infrastructure is usually geographically dispersed. Hybrid cloud provides the option to pick which infrastructure (private or public) to use based on the criticality of a given application or service. Applications where availability and end user response time are critical may be better suited for public cloud deployment because of the ability to provide a resilient localized IT infrastructure. For example, an enterprise with customers in both the United States and APAC can leverage “localized” public cloud resources on two continents for their web services, while other critical applications (i.e. nightly order processing) may lend themselves better to private cloud.
- Agility –The Enterprise can readily build out a “virtual” IT infrastructure and use it to develop or test new and different applications and technologies. Trying out different scenarios in public cloud without affecting private cloud allows for fast time to value.
- More effective leveraging of IT personnel – A more targeted and effective use of hybrid
cloud allows IT to focus on tasks that matter more for the business. For example, a datacenter that is in need of more computing resources or storage can get that provisioned in a matter of minutes in public cloud, whereas it may take days, week, or even longer for IT to evaluate, purchase, and deploy in private cloud. IT personnel are finite, there is an opportunity cost associated with tying up key IT personnel, as there can be delays in advancing other technology initiatives.
Hybrid Cloud – Software as a Service
Enterprises leverage hybrid cloud in any combination of IT models including as SaaS, IaaS, and PaaS.
- Software as a Service (SaaS) is the provisioning of applications in public cloud.
- Infrastructure as a Service (IaaS) is the provisioning of IT resources in public cloud. For example, the provisioning of storage, servers, and network. The resources provided are “elastic” meaning they can grow or shrink based on demand. Typical use cases might be web hosting, storage, backup, testing, and big data analytics.
- Platform as a Service (PaaS) includes all the IaaS attributes plus a “platform” to develop and deploy applications.
The widespread adoption of hybrid cloud has resulted in enterprises that are quite cloudy, meaning a private cloud that is integrated with multiple public cloud providers, running a mix of IaaS, PaaS, and SaaS.
- Consider an enterprise that is a hybrid of public cloud with SaaS - perhaps using Salesforce, Office 365, and Oracle ERP. Enterprises will typically choose multiple public cloud providers when their priorities revolve around deploying best-of-breed solutions for each of their business services. An additional benefit is a reduction in risk because the enterprise is not putting all its eggs in one basket with a single SaaS provider.
- An enterprise can also implement a hybrid using mixed IT models for instance, private cloud along with both SaaS and IaaS. Let’s take the example where the applications are delivered (SaaS) by one set of cloud providers, while the backup (IaaS) is delivered by a separate provider. Again, we can see hybrid cloud helps mitigate risk, if for some reason a SaaS environment is compromised then the backup has already been segregated in a secure and separate infrastructure.
Working with multiple public cloud providers certainly does introduce a level of complexity, especially as it applies to integration. How do you link the data? How do you take advantage of workload management and all the other things public cloud has to offer?
IT must deliver a consistent and dependable user experience, which means the data has to flow seamlessly and securely between all systems, private and public. The implementation can be a daunting task because of the complexity that comes with multiple application and environments.
Getting all these components to work together is no small feat, it is all about the applications, the storage, the network and everything in between. Technical expertise is needed to help design and implement such a system. A number of skillsets are required including being able to work with different APIs (i.e. SOAP or REST), scripting, working with different portals, or familiarity with any number of cloud integration platforms. Integration is expensive and needs to be factored in any TCO calculation.
Hybrid Cloud – Infrastructure as a Service (IaaS)
It is a safe assumption that few enterprise IT environments came to be directly from the cloud, most all started off in some way as an onsite/private cloud implementation. Augmenting these environments is the most logical progression and IaaS does just that. Integrating private cloud with IaaS is perhaps the most prevalent service model because of the relative ease at which it can be implemented.
IaaS is about leveraging additional IT resource from the public cloud including CPU, storage, and network to interact seamlessly with a private cloud to deliver IT services. IaaS offers elastic growth because resource utilization can grow or shrink based on demand. Enterprises operating a hybrid of private cloud and IaaS have the flexibility to balance some or all of the IT resources for a given IT initiative to public cloud services. Depending on the provider, public cloud resources can be unbounded.
IaaS is ideal for enterprises that not only want granular control of the IT resources: server, storage and network, but also have control of the applications – making integration less complicated than with SaaS providers.
The big win – Enterprises use and pay for only what they need, there is no capital outlay, they don’t have to worry about cooling, power, hardware failures, or any of the issues associated with a physical set of resources.
The cadre of IaaS providers is substantial with Amazon’s AWS and Microsoft’s Azure leading the way. In general, if your needs are service oriented that might tip the scale in the AWS direction. However, if you’re heavily invested in the Microsoft technology stack then Azure is certainly worth a closer look. Again, there are quite a few IaaS providers, each with distinct advantage so really do your homework.
- Does the size of your enterprise fit the demographic of your IaaS provider?
- How does the IaaS provider address IT security issues?
- Where are the IaaS datacenters located in relation to your constituents?
- How resilient is the IT infrastructure, what kind of disaster recovery is in place?
- What kind of management tools are in place?
Managing and monitoring Hybrid Cloud
The availability and performance metrics that IT needs to monitor are not unlike that of any private cloud. When it is all said and done, it is all about making sure that resources be they compute, storage, or network are effectively leveraged. IT’s priorities should focus on:
- Maintaining consolidated view of IT resources utilization
- Securing the hybrid infrastructure with consolidate log monitoring
- Monitoring and balancing workloads based on the enterprise’s policies.
Hybrid clouds are an increasingly integral part of the IT landscape. They can save the enterprise time and money with computing resource flexibility, while allowing enterprises to maintain control of critical data. Hybrid cloud certainly comes with its share of challenges, especially when it comes to integration.
Recognizing up front that perhaps the most difficult part of the equation is determining how to best integrate all the components will go a long way towards building a hybrid environment that operates in a truly seamless fashion.