Over the past few years there has been a lot of discussion over cloud architectures, cloud deployments and the definitions that go with them. We have come to understand the terms public cloud and private cloud. But the term Hybrid cloud has been a bit hazy and there have been many definitions and descriptions of what a hybrid cloud really is.
Here is one definition put out by Forrester for a hybrid cloud. “One or more public clouds connected to something in my data center. That thing could be a private cloud, that thing could just be traditional data center infrastructure.”
If you consider this definition then you can look at the hybrid cloud as the combination of one or more public cloud providers (such as Amazon Web Services or Google Cloud Platform) with a private cloud platform which an organization has set up and is using for its own in-house computing and for hosting systems of record. Now the public cloud providers could also set up a private cloud for you. And this could be either in their infrastructure or in the company's own data center which could be on-premise or located elsewhere. Essentially, when we say hybrid, it means being able to securely integrate and communicate securely between all the computing environments that a organization may setup one way or another.
Hybrid clouds are useful when organizations need to keep sensitive data in-house or are unable to move data onto the public cloud due to governmental regulations. It also useful when legacy systems cannot be moved to the cloud due to the nature of the workloads. It should be noted here that you cannot just move everything to the cloud. Only those workloads that are feasible and applications that lend themselves to being able to work in the cloud can be moved. Given this it becomes necessary to set up a hybrid cloud environment where a part of the computing infrastructure continues to remain in the organization’s data centre which can be on-premise or outside.
Applications which can be migrated to the cloud need to be first evaluated to see if its feasible to move them to the cloud. This is an exercise by itself where the application’s computing and data architecture is studied and evaluated to find out its feasibility of moving to the cloud. Those that can be moved are then put through a cloud migration plan. Those that cannot be moved are retained on premise or in the company’s data-centre. The overall hybrid architecture will then need to consider secure connectivity between the on-premise applications and the on-cloud applications.
An enterprise architecture provides for integration across all the applications and computing and storage resources. This will also consider all the security aspects that need to be built into the architecture for a hybrid cloud implementation.
The following diagram is a simple representation of a hybrid cloud deployment.
The diagram shows at a high level what the different components making up a hybrid cloud configuration are.
The public and private clouds together constitute the cloud environment that is used by the organization for its computing and storage needs. This block is where a majority of the systems and storage can be located. Typically the customer engagement systems are based in the cloud. As this involves web, mobile, social and analytics technologies, the cloud platform is most suited for deployment of applications based on these technologies. The applications typically hosted in the cloud are the customer engagement applications like the mobile apps, the customer and vendor portals, the Customer Relationship management systems (CRM), the analytics systems and the digital marketing systems. There are times when some of these applications may be offered as a service by other vendors in other clouds, for eg. CRM may come from a vendor like salesforce.com who has their own cloud environment, office applications may come from a vendor like Microsoft who have their own Azure cloud hosting environment, a vendor like SAP has their own cloud environment and IBM has their own. If an organization has applications supplied by these different vendors and also has built its own web and mobile apps for customer engagement and portals for their partners, then all these applications will have to work in conjunction with each other and also with the enterprise applications (like ERP, HRMS, Finance etc) of the organization itself. This is made possible by integrating all the various applications across the different cloud platforms and the in-house enterprise applications using enterprise integration.
The organization’s cloud platform should be able to provide secure connectivity between its own enterprise applications and the other cloud based applications provided by other cloud providers. Secure connectors, VPNs, firewalls etc. all need to configured together to be able to provide secure access to enterprise applications and data and for the secure transfer of data between these various environments. It is advisable to have the data and the applications using the data in the same cloud environment for performance reasons but its not always possible due to various factors and hence it is important to be able to maintain secure connectivity between the applications and the data.
There has always been a resistance to moving to the cloud from the CIOs in organizations due to various reasons, but that is a trend that is now declining and the benefits of the cloud far outweigh the unfounded fears that have kept organizations from moving to the cloud. Today it is not an issue. The hybrid cloud was not understand in the earlier days and hence the reluctance to move any application to the cloud. But today given the stability of cloud implementations and the security provided along with the secure connectivity between public cloud, private cloud and data-center applications, it is no longer an issue.
A typical use case for a hybrid cloud implementation is described below.
Assume that there is a logistics provider who provides services to various e-commerce organizations in terms of warehousing, shipping and delivery of items to its end-customers. To be able to provide service of the highest quality it is imperative that the provider be able to monitor and track all shipments from the time they are picked up or packed to the time they are delivered. This means keeping track at all stages of the shipment. Apart from the shipment it is also necessary to be able to track all the partners that are involved in the operation and be able to manage them efficiently. This means that all the systems involved need to be able integrated together.
When an ecommerce site makes a sale, the order details will be flagged off to the respective vendor of the product and the logistics provider who will service the order. This requires that the logistics providers systems be integrated with the ecommerce site. Once the order is registered in the system, the warehouse, which could be at a totally different location, is informed so that the item can be picked and made ready to be shipped. The transport management system and fleet management systems are also integrated and these may or may not belong to the logistics provider as they could be 3rd party providers. The trucks transporting the goods themselves will be fitted with onboard devices that will enable the logistics providers to track the movement of the tracks. The warehouses and the transport hubs will be fitted with devices at the loading and unloading stations and will have readers to read tags on the shipments. All this data from the devices and readers and other sensors are collected and relayed through gateways at these locations to a platform in the cloud which receives the data in realtime. Updates on the delivery are relayed to the systems in realtime from the handheld devices of the delivery boys. The delivery boys themselves could have handheld mobile apps that help them manage their routes and delivery as well as allow their supervisors to manage their activity. All these apps and data is handled in the cloud. All these applications then need to be integrated with the back-office systems that handle the finance and reporting for all this activity. These systems could be located on-premise at the company’s location or in a datacentre. The status updates on the delivery are made available both to the ecommerce provider as well as the customers on both the web and the mobile applications.
The point here is that with so many different actors, systems, applications, devices, and environments, it is only by means of an integrated cloud environment that it is possible to operate in a cost-effective and efficient way without performance and customer satisfaction suffering. The story would be a lot different if each of these applications and systems were located in silos and there was no integration or communication between them. Only a hybrid cloud environment makes this possible.