Cloud: Alternative Cloud Roadmaps, Getting from Here to There

If you’re currently investigating how your organization can begin taking advantage of using the cloud, in a new white paper Gartner outlines a framework to use that gets you started down a suitable path of investigation.

Gartner generalizes five different very high-level alternative paths to the cloud that you might take.  For many organizations the best option will be to simply select a SaaS solution.  Larger organizations, particularly those with large IT and development staff, the different degrees of investment in preparation for moving an application to the cloud should be considered.  The five pathways that Gartner identifies are the following:

Software as a Service (SaaS) This is by far the the easiest way to jump to the cloud, simply by starting to use a pre-packaged solution.  A potential major hurdle with this approach though may be the need to migrate legacy data into the new cloud-based one.  Gartner research director Richard Watson, author of the report, also added that “this option avoids investment in mobilizing a development team when requirements for a business function change quickly. Disadvantages can include inconsistent data semantics, data access issues, and vendor lock-in.”

Rehosting on Infrastructure as a Service (IaaS).  With this option, you take an existing application and simply redeploy it onto a server managed within the cloud.   This assumes that that the software being moved is compatible with the target cloud environment.

Refactoring for Platform as a Service (PaaS) The feasibility of the previous rehosting option has a lot to do with whether the architecture of the software application allows it to simply be moved.  There are also issues with the hosting environment — the cloud hosting environment needs to be one supported by the application software — the physical hardware, operating system, database and other elements of the environment all need to be supported by the application which is being moved.  A number of other factors may be issues too, for example, if the application was not designed with the cloud in mind, there may be a number of issues around security and authentication that would need to be solved.  The application may need to be refactored and changed to run in the cloud environment.

Revising for IaaS or PaaS This option is the more comprehensive than simple refactoring.  It uses and expands on the tasks necessary to rehost and refactor existing applications.  This method involves some amount of rearchitecture of the core application to better take advantage of cloud capabilities.

Rebuilding on PaaS With this approach you need to rearchitect and build your application from scratch to work in the cloud PaaS.  Rebuilding a new application is  an expensive undertaking, and as more companies realize the benefits of sticking with the configuration of ready-made SaaS software, this is one option that should be really be considered very carefully before investing in.