Platform games: choosing a PaaS when building cloud foundations

The internal mechanics of cloud computing’s engine room have been variously described and detailed by so many vendors that many customers will arguably have felt more than just a little confused by the choice of core components needed to establish a cloud services connection.

As Cloud Pro has previously detailed, on top of cloud’s Infrastructure-as-a-Service layer (and beneath the cloud services application layer itself) lies the Platform-as-a-Service (PaaS) middleware layer. 

So how does a company evaluate one PaaS from another? Should the decision rest primarily on cost as a starting point? Is the range of applications being supported the most crucial buying factor? Does it come simply come down to service and technical support? If one PaaS costs more than another, how do customers work out if the extra expense is justified? For that matter, where do we go for guidance on this ever-expanding catalogue of technology?

The portable cloud
Red Hat’s VP and GM of cloud Scott Crenshaw has explained that each PaaS option can be distinguished by its choice of supported programming languages, its Service Level Agreement (SLA) and its “portability” ie whether applications and data are portable between public cloud and on-premise private clouds in a hybrid model.

But more fundamentally for Crenshaw, the choice comes down to interoperability and openness i.e. a cloud PaaS built on open standards, with open application programming interfaces (APIs) under an over-arching open source community-supported model are the key differentiating factors for the best PaaS choice, as far as Red Hat (the “pure play” open source company) views it at least.

If two apparently similar PaaS offerings are priced some distance apart, there may be an underlying reason beyond simple branding. The amount of supporting infrastructure (from size and scope of data centre, to employee training and skills through to service and support offerings) behind the PaaS provider should be a good indicator as to its longevity and ability to provide deliver new innovations as they come to market. Buying decisions between the two should then be dictated by the scope of the customers’ needs.

It comes down to a question of business risk. For companies looking to cloud services to fix a short-term problem, a cheaper PaaS model may be fit for purpose enough for the job in hand. For companies looking to move to the cloud model with some permanence (which will logically be most firms in this case), a pricier PaaS option may be a better option if it represents a brand from a provider who is going to be around for a while.

Making a PaaS (decision)
UK chief technology officer at SAP Adrian Simpson argues that making the PaaS decision will be heavily influenced by individual company needs and how far their vision extends. “It isn’t about a firm's size or which industry they are in. It’s down to whether to move to cloud is for tactical quick win, or whether it is a more strategic longer term bigger scale decision.”

“Choosing a PaaS option should not primarily rest on cost as a starting point. The value from the total investment should be the most important thing. The range of technologies being supported won’t necessarily be the most crucial buying factor either, however, it is likely to be an influence on the buying decision. Organisations will want to know they have the right skills in-house to support the investment. If they need to bring in new people or trains people to have these skills, this will of course increase the cost and investment time,” said Simpson.

The three PaaS types
So once again, if we can agree that not all PaaS offerings are created equal, how do we view one in comparison to another? We might usefully classify one type of Platform-as-Service as a development-focused PaaS, where programmers have access to a full set of tools, components and APIs in order for them to create new services that specifically plug into and take advantage of the option to draw on elastic computing power. The development-focused PaaS example is clearly seen in Heroku, which supports several powerful programming languages.

“A second type here would be the business-focused PaaS,” says Matt Davies, director of Business Process Management (BPM) specialist Cordys. “According to Gartner, in this approach capabilities such as integration, BPM and user experience sit alongside the application development platform; so this is where we're seeing the intersection of business and IT. These capabilities tend to be more focused on tooling for non-developers, business and end users.