A few years ago, understanding costs in the cloud was refreshingly simple: pay by the drink compute, storage and network. But as the market matured, it’s gotten more difficult.

Vendors have begun to differentiate. Third-party add-ons have filled specific gaps in features. An explosion of providers are competing for an ever-larger chunk of budget from an increasingly diverse customer base.

About a year ago, CenturyLink launched an online Cloud Total Cost of Ownership Tool with one simple goal: provide an unbiased apples-to-apples comparison between our offering and selected competitors. It has helped buyers understand the intricacies of the cloud computing market, and what the best value for them might be, even if it’s not CenturyLink.

Centurylink Cloud Total Cost of Ownership Tool

To increase the utility of this app, we’ve contributed the Cloud TCO Tool to the open-source world under the Apache 2 license. You can view the repo on Github.

If this sounds familiar, it's because we did something similar with our Cloud Services Estimator.

How does the TCO tool simplify cloud comparisons?

Normalized Compute Performance

Performance across providers is hard to compare for two key reasons:

  • Instance sizes. Some providers have a “T-shirt” model with fixed-instance sizes, while others offer the flexibility to resize on the fly.
  • Underlying hardware. Is your virtual machine running on a high-end physical box? Or is it a low-cost instance operating on end-of-life gear? How much of the physical host allocated to your VM? The “bang for your buck” is highly variable.

In the tool, users can toggle “match performance” on or off, depending on if this metric is important to them. The underlying formulas use data provided by a comprehensive CloudHarmony survey done last year, along with some simple math to extrapolate what performance looks like across a wide range of VM sizes.

A Closer Look at Guaranteed Storage Performance

Want SLAs around a given level of storage IOPS? That’s extra. Are common “floors” and “ceilings” of performance good enough, or do you need greater assurances?

Built-In vs. Bolt-On

Some cloud providers bundle management and governance tools on top of elastic infrastructure to simplify the administration of environments. This is what CenturyLink provides by default.

Others provide a looser, “do-it-yourself” model – charges for these services are added to the non-CenturyLink providers.

Toggle the options in the header bar of the tool and see how the costs of CenturyLink’s “built-in” feature set compares with the expense of other clouds plus popular add-ons like RightScale and Alert Logic.

You Have the Power

Most importantly, though, the basic model of the tool can now be modified by the community for whatever scenario is relevant to the user.

The great thing about open source is that the original contributor cannot possibly conceive how the tool will be modified and used by others. We’re looking forward to seeing how our customers and partners modify this tool to simplify cloud costs for their own specific scenarios!