In the first part we looked at public, private and Hybrid Cloud and their characteristics. In this part we will look at the common characteristics of business critical applications. In the second part , we looked at how some of these characteristics relate to the different types of Cloud infrastructure. In this final part we will look at he lifecycle of a business critical application in the cloud and the conclusion.
Lifecycle of a business critical application in the cloud:
Let us look at an example of how an application can leverage different types of clouds during its lifecycle. SAP provides a suite of applications that serve the enterprise business community for use in the operations of their business. We shall take the example of an SAP application leveraging the cloud during its lifecycle
Here are some of the common steps in the applications deployment lifecycle:
(1) Proof of Concept
(2) Development
(3) Testing & QA
(4) Production
Phase 1: Proof of Concept:
During this process the business evaluates if the SAP ERP application meets its needs. The business is also looking at how the application would impact its business processes. The proof of concept would help validate the functionality of the application and its adaptability to the business.
Figure 8: Proof of Concept
Cloud Requirements:
Meet minimal requirements for the application to run.
The application will be used only periodically by a small set of users to validate the functionality required by the business.
The entire POC would be completed in a few weeks.
The time to get the infrastructure up and running should be minimal
Should leverage the prebuilt stacks from SAP
Best Cloud Fit:
Public Clouds provide pay as you go infrastructure that can be provisioned in a matter of minutes. They quite often provide prebuilt application stacks that can be leveraged for the POC. On completion of the POC, the infrastructure can be torn down. Public Clouds are the most suitable for POC.
Phase 2: Development:
The POC had validated that the application was a fit for the business. The next step in the process is to perform customizations of the application to suit the business needs. The development environment needs to provide for all the tools and the infrastructure needed by the developers to be productive.
Figure 9: Development
Requirements:
Have robust tools for development
Ease of setup and use
Ability to collaborate across a team of developers
Cloud Fit:
Developers, due to their ease of setup and use, increasingly prefer public Clouds or SAAS providers. They also provide a vast array of tools to help developers be productive.
Phase 3: Testing/QA:
During this phase the application are tested against internal data, processes and applications.
Figure 10: Testing & QA
Requirements:
Access to internal data
Interact with related applications
Increased security requirements
Cloud Fit:
Private clouds best suit the requirements of the testing phase. The fact that testing is done across the stack with internal data and need to interact with other applications, makes it suitable for Private cloud environments.
Production:
After completion of testing, the application is put into production for business use.
Requirements:
High performance, scalable and secure infrastructure
Real time interactions with other applications and external data
Highly available to meet business needs
Robust operations with proactive monitoring framework
Backup and Recovery
Disaster Recovery
Figure 11: Production
Cloud Fit:
Private clouds are best able to meet these requirements. Public clouds are unable to meet stringent SLAs and can be expensive for round the clock use. Backups and Disaster recovery needs are best met by a hybrid cloud strategy leveraging both public and private clouds.
Conclusion:
Business critical applications have their unique requirements that need to be carefully considered for cloud based deployments. We looked at the top ten factors affecting BCA and analyzed how public and private clouds stack up against these factors. Neither public nor private clouds can entirely meet all the needs of BCA. By leveraging the strengths of public and private clouds in a hybrid cloud model one can address all BCA needs efficiently in a cost effective manner.
