Conventional wisdom would lead you to believe that you should migrate all your IT resources to the cloud. But not all apps are created equally, nor should they all be considered for cloud migration. So which of your apps are really viable candidates for the software-as-a-service (SaaS) model?
The first criterion to consider is cost. Is it cheaper to deploy applications via SaaS than to maintain the software on premise?. One important consideration is whether and how your cloud provider charges for cloud data access. Many, for example, let you upload as much data as you want for your monthly subscription fee but charge a per-megabyte fee for data downloads. Do the math to make sure there are savings to be had by moving the app to the cloud. Also, check on the provider’s policy for increasing the price of hosting resources such as compute and memory power as you scale your apps to reach more users.
If it looks like you can save money, then take a look at the following considerations:
• Operations: It’s easiest to migrate an application that’s already been virtualized to the cloud, since the cloud is also a virtual environment. But what if that app has on-premise dependencies, such as being tied to Active Directory or requiring user access to a SQL database to function? These complexities might cause migration pain. Also, make sure your chosen cloud provider supports the OS upon which your application runs. That could be a deal-breaker for app migration.
• App performance: Users access cloud apps over a WAN link, which introduces some distance-based delay into the equation and could affect performance. So you might want to check on your provider’s cloud point-of-presence locations (the nearer to your sites, the better). Make sure your WAN link has both adequate bandwidth and lets you control traffic with enterprise-grade quality-of-service (QoS) tools. In fact, for performance reasons, it can be beneficial to use a WAN provider that has been certified specifically to work with your cloud provider.
• Security and disaster recovery: The stricter the security requirements, the less likely the app is to be a cloud contender. It’s more difficult to enforce customized policies in someone else’s network. However, if off-the-shelf security and compliance solutions meet your app’s security needs in your data center, moving it to a SaaS model is likely doable. And if your disaster recovery requirements are strict, the cloud provides a place where you can get almost unlimited backup across geographies, so your data could be safer from floods, fires, and attacks than in your own data center.
With these general considerations in mind, the following application types usually make strong cloud candidates:
* Enterprise email
* Collaboration and unified communications
* Project management
* Customer relationship management (CRM)
* Accounting and finance (for the cloud’s backup and recovery advantages)
Migrating apps isn’t an all-or-nothing proposition, given the often-complex mix of legacy apps, one-off security requirements, and old operating systems that most enterprises continue to support. For the time being, the best approach likely involves moving less customized or new apps to the cloud while continuing to operate mission-critical and security-heavy apps on-premises.