If your enterprise got picked for a makeover on a reality TV show, one of the first things the judges would probably do is ask why you haven't moved to the cloud. Streamlining your ALM, ditching unnecessary infrastructure, and reducing maintenance costs can be so slimming. But the fact is that not every single app in your wardrobe is going to be a good fit for a SaaS or PaaS based solution. Let's take a some cloud adoption strategies, while focussing on a few scenarios where keeping an app out of the cloud might be the wiser choice.
You don't need to rebuild every single app as a cloud app. Sometimes, it's just not worth the time and trouble.
Migration versus total transformation
Before we dive in, we should probably point out that industry experts at Forrester say you shouldn't move your existing apps to the cloud at all. Apparently, re-architecting isn't enough to solve the problem. "If your traditional applications are an architectural mismatch with cloud platforms, it's an expensive and costly route to try and rearchitect them for the cloud." Instead, "Cloud applications should be built from the ground up for cloud." Otherwise, you aren't really capturing the full benefit of the cloud for features like scalability or service oriented architecture.
What's our take? Some apps do need to be radically redesigned before they are ready to launch in the cloud. But you don't need to rebuild every single app in your portfolio as a cloud app. Sometimes, it's just not worth the time and trouble.
Embraceable or Replaceable?
If your enterprise development team was into some really cutting edge stuff twenty years ago, they may have created a passel of custom apps to meet your business needs. Each of these apps may be as precious to your organization as your grandma's crocheted afghans. But many of them can probably be replaced with off-the-shelf SaaS apps today for a very low price. If the function of a legacy app can be taken over by a cloud-ready app, an "out with the old, in with the new" approach makes more sense.
Replacement can also be a good idea for apps that have complex and restrictive licensing agreements. New cloud apps are more likely to have generous license terms. Some are even open source, freeing you to use them in ways that suit your business in the new millennium. If you choose replacement over migration, be ready to adjust your business process or workflow slightly to accommodate the new app.
Do you have legacy apps cluttering up your mainframe that you just can't bear to part with? Do you think you might need them in the future? These are like the skinny jeans in your closet that you hope you can fit back into some day. Apps you aren't actively using and that are far from mission critical can take the back seat in your migration strategy. You can always redesign or rewrite them later if your business needs change. With a few cloud-friendly enhancements, you can keep them on your existing infrastructure and only extend them into the cloud during peak times. This method might be a good way to deal with apps that your business uses once a year and that don't need to be accessed from multiple user-locations. Even if you aren't fully leveraging the scalability of the cloud for maximum effect with minimum cost outlay, that's OK. The cost of recreating a legacy app that only sees occasional use might outweigh the savings of having a completely cloud-compatible app.
Note: Other rarely used or reference-only apps might actually be migrated to the cloud but not deployed if you really want to trim your on-premise hardware needs. That way, they can be de-activated when not in use to save even more money.
This final category includes apps that simply aren't safe to put in the cloud. There may be compliance issues that aren't adequately addressed in the public cloud. A private cloud offers more choices including the ability to sequester your apps on dedicated hardware. But even with major cloud players getting the nod from big government (including the CIA), you may still have concerns about migration. If you don't fully understand the risks and the available safeguards, you're not ready to move these apps yet. This doesn't mean you'll never shift these super-sensitive apps to the cloud. It just means you need to build up your security-confidence before you bust that move on the cloud dance floor.
What types of applications are most easily migrated to the cloud? Let us know.