Alex Barrett wrote an article
I would like to add to...
If an application is due for a refresh, why settle for just a facelift via an incremental hardware upgrade or new GUI? Instead, why not go whole hog and re-platform the application on a state-of-the-art cloud platform that delivers scalable performance, flexibility and resilience—not to mention an operational expenditure (opex) rather than capital expenditure (capex) model?
...with, why not update it with a Portal, a Service Oriented Integration Platform and augment it with some Platform as a Service Rapid Application Development technology to add situational applications?
and to ...
Enterprises are increasingly large consumers of Software as a Service (SaaS) applications, the classic examples being Salesforce.com for customer relationship management and Workday for payroll services. Now, some internal IT departments are exploring whether it makes sense to follow suit and re-architect in-house applications as cloud-hosted multi-tenant applications—private SaaS apps, as it were.
...with yes we can do exactly that, but we can also take legacy applications, put them into a virtual instance and access it from our Portal or ESB.
Alex is right on target with...
Unfortunately, re-architecting a legacy single-tenant application for multi-tenancy is easier said than done.“It’s a monumental task,” said Brian Hoskins, principal product manager at LANDesk, the systems management software provider that is on a three-year journey to “SaaS-ify” its traditional service desk tools, and that is doing the same for its systems and security management offerings.
...we have seen other "SaaS-ify" projects abandoned after two years or more. We can convert many single tenant applications to Multi-Tenant in less than an hour, sometimes without even the source code.
Then there is our piece....;-)
Open 4 Business Online (O4BO.com) is based in Hong Kong, and recently used Corent MTS to create a SaaS service that runs on the IBM SmartCloud from a standard catalog of open source business software, including Openbravo for ERP, Pentaho for business analytics and SugarCRM. Mike Oliver, the founder of O4BO and also a former Corent employee, said conversion times vary, but that he could convert some applications in less than an hour.“It depends on the application. Some are well-designed, but others have idiosyncrasies or, frankly, poorly designed code,” Oliver said. Having access to the source code, however, is not a requirement for Corent MTS, Oliver added.Oliver said he has talked about Corent MTS to a number of enterprise shops that are intrigued by the possibilities. One U.S. health care consortium, for example, is thinking about using it with its subsidiaries across the U.S. Of particular interest is that the converted application can use either shared or dedicated databases, which is an important consideration in health care, where regulations vary from state to state.
You can read the whole article at http://tinyurl.com/b5vrb3r