Trevor Pott's guide to pricing up the cloud

IaaS

It is increasingly easy to realising value from hosted cloud services. Not having your own IT plant removes direct costs; equipment, licensing, power, cooling, rent and other overheads.

IaaS, or infrastructure-as-a-service, enables sysadmins to refocus efforts away from keeping the lights on; allowing them instead to focus on R&D that moves the business forward by using technology to streamline other business elements.

IaaS is the ability to take your existing infrastructure – typically, virtual machines – and host it in someone else’s data centre. The reason to do this is simple; large IaaS providers have redundant bandwidth, power, cooling and global distribution unavailable to smaller organisations.

IaaS providers can also give their customers the ability to rapidly provision servers and bandwidth to deal with spikes in demand, say, or to roll-out services much more quickly. (The Open Group explores the ROI of Cloud and elastic services more fully, here.)

Depending on circumstances IaaS may very well allow organisations to get by with fewer sysadmins. This is an important consideration, as payroll is part of the burden companies are looking to the cloud to help them avoid.

But users of IaaS will still typically require at least one sysadmin. Hosted infrastructure is still infrastructure; management of applications is not normally part of the deal.

Software as a Service

SaaS is the easiest category of cloudy offering to understand.

A developer writes an application, hosts it somewhere on the internet and you pay for it. A subscription model is typical, but by no means a requirement. SaaS applications are typically delivered through a browser, but not always. Hosted Exchange is one example offering full functionality via both traditional and browser-based email clients.

For SMEs, cloud-based software gives them access to software that they could neither afford to build themselves or buy in, or it could free up resources for business-critical work.

For instance, The Register, home to about 50 staff, has three software developers, who concentrate on the home-grown content management system, improving the websites and reader accounts systems (and a bit of sysadmin work.) CRM, accountancy software, office apps and email are all contracted out to SaaS providers.

Do companies really need to run their own email systems? Hasn’t this technology been around for long enough that we can trust someone else to take care of it without problems? What about the corporate instant messenger, spam filtering, malware protection, web hosting, CRM or dozens of other “basic services"?

These are mundane items; no individual service consumes an inordinate amount of time. Yet in my environment, these “minor” services occupy dozens of virtual machines on several servers. Maintenance overhead alone is at least a month’s worth of my time every year. This is before taking into consideration of testing and replacing the relevant hardware each refresh cycle.

Integration of these services is where the real time is consumed. Cloud providers with multi-application “stacks” can deal with some of this as well.

For those applications sourced outside of a stack, integrating them into existing – or planned – infrastructure is rarely more difficult than integrating those applications would be were they run locally. In the same vein, if you have a stack of applications running locally that are all tightly integrated, breaking this up to host elements elsewhere makes little sense.