If you're thinking of migrating at least some legacy applications to the cloud, you may bedealing with the same concerns as many of your peers: integration, security, total cost of ownership, reliability, licensing. Wait, licensing? Doesn't moving apps to the cloud remove many of the hassles of convoluted and costly licensing agreements for on-premise software?
Maybe so, but licensing can also present a hurdle in moving the apps in the first place. According to an article on SearchCloudComputing.com, at least some cloud users had to renegotiate their software agreements as some of them required apps to be installed at a specific site. Said Bob Nordlund, assistant vice president for Enterprise Risk Management and Actuarial Technologies at The Hartford Financial Services Group:
We had to go back and reverse engineer a lot of the agreements [with older systems vendors], as a lot of them are location specific.
Interestingly, large companies like The Hartford and Johnson & Johnson, another company mentioned in the article, are focusing less on high-level issues and more on nitty-gritty concerns such as licensing and service-level agreements as they consider the cloud, said William Fellows, a principal analyst for the 451 group.
In addition to licensing snafus, companies may encounter difficulty in migrating legacy apps that have been highly customized, I learned from several folks whom I interviewed earlier this year for a story on how companies can take advantage of cloud computing. For instance, a Hosting.com customer was unable to move a proprietary sales-delivery application into the cloud because it involved implementing a custom piece of hardware on a server's back end, said Steve Howard, Hosting.com's director of operations and infrastructure. He told me:
Unfortunately, you can't have a unique piece of hardware pushed into a public cloud. On top of that, the app would have to be cloud friendly, which usually isn't the case with these types of applications.
In another example, Jonathan Bryce, co-founder of Mosso, Rackspace's cloud computing division, told me an Oracle database, using a specific rack cluster, specific storage, specific configuration for a database server and specific network gear, also isn't a good candidate for the cloud: He said:
You can't specify all of that when you deploy in the cloud.
Generally, of course, the higher up the "cloud stack" a company goes, the less control it maintains over its applications. Platform-as-a-service offers the greatest amount of control and software-as-a-service the least.