Cloud computing isn’t the most complex of concepts, but the various options can feel confusing at first glance. Choosing between SaaS, PaaS and IaaS for your cloud computing service becomes a lot more straightforward when you understand it’s all about finding the right balance between convenience and control.
What is a Cloud Computing Service?
Before we get into service options, let’s just recap what we mean by cloud computing. At its simplest, it means taking advantage of the fact that for most business applications it doesn’t matter where digital information is physically stored.
The most basic cloud services involve storing data outside of your physical premises (sometimes in multiple locations). More sophisticated and useful cloud services involve the processing of that data happening outside of your premises. In both cases the main advantages are scalable access to greater capacity and processing power, and less reliance on maintaining and securing your own facilities.
Exactly what you get from a cloud computing service provider varies from package to package. But the various options are most commonly put into three broad categories:
- Infrastructure as a Service (IaaS)
- Platform as a Service (PaaS)
- Software as a Service (SaaS)
In each case, the “as a Service” refers partly to the fact that it all happens elsewhere rather than being a product you buy and use on your own premises. Also, generally these involve paying a subscription-like fee to use the service for a particular time period.
What are the Differencesin Services?
Exactly what each of these three options entails can vary from provider to provider. It also depends on whether you are using cloud computing to perform a task for your business, to deliver your own technology to customers, or both. Different providers may have different definitions. So it’s always important to check exactly what services you are getting for your money.
In most cases, the biggest different between the three types of “as a Service” is the balance between what aspects of IT you manage and what aspects the service provider manages, usually off-site:
- Software as a Service has the most elements taken care of by the service provider
- Infrastructure as a Service has the fewest elements taken care of by the service provider
- Platform as a Service falls somewhere in between.
Let’s look at the three categories in a bit more detail.
Software as a Service
Although SaaS usually covers the widest range of services, it’s also the easiest to understand in everyday use. When you use SaaS, you don’t run the software on your own computers. Instead you access it remotely through the internet, commonly through a web browser. If you’ve logged in to Gmail, you’ve used SaaS.
A better example for businesses would be Microsoft Word. Back in the day businesses had to buy a copy of Word and install it on their computer. Today many users opt for a version such as Office 365 where you pay a monthly or annual fee. This fee covers remote use for a set period with no need to pay for updates and new editions. If you choose, you can have documents stored remotely so you can access them from any machine.
In the most basic terms, Software as a Service works and feels like any other software designed to solve a business problem.
Platform as a Service
Ironically, the sheer simplicity of using SaaS as a customer hides the fact that it’s got the widest range of components and features. Platform as a Service shifts the balance a little by having the customer take care of a couple of key elements.
In most cases a Platform as a Service user will run applications and hold data on their own computer system. That still leaves plenty for the service provider to do. It’s a bit of a simplification, but as a general principle with PaaS:
- You take care of your own applications and data.
- The PaaS provider takes care of the software and hardware that makes your applications and data work properly.
To put it another way, most commonly SaaS involves using somebody else’s tools to carry out specific tasks for your business or your customers. PaaS is more about creating your own tools to carry out those tasks, but not having to worry about all the underlying software and hardware.
In specific technical terms, PaaS usually includes the provider taking care of three particular elements:
- Runtime (the precise order computers have to carry out individual tasks to make your tools work.
- Middleware (software that makes your tools work smoothly with other tools and services).
- The underlying operating system.
Infrastructure as a Service
In the simplest terms, IaaS means the service provider takes care of the hardware and you take care of everything else. IaaS gives you almost complete flexibility and control (and responsibility) for how everything works on the software side. The IaaS provider then takes care of storing data, physical processing on a remote server, and physical networking.
The idea is that subscribing to an IaaS package has the same effect as adding more servers to your system without the expense (and potentially wasted capacity) of buying more physical equipment and putting it on your premises.
The only real exception to this principle is that IaaS often includes virtualization. That means taking space on the service provider’s servers and simulating one or more computers for your network.
How to Choose
These are some of the questions you need to think about when choosing a service provider and which form of cloud computing to opt for:
- How much control and customization do you need?
- How sensitive is your data and what legal restrictions apply to the way you and other handle it?
- Is your computer network and your internet connectivity reliable?
- How big is your IT department and what is its level of expertise?
- How quickly are you likely to grow? Will your computing needs expand rapidly?
- Do you prefer buying equipment and software outright or subscribing to a service?
You also need to watch out for a couple of issues with cloud computing services. Firstly, watch out for vendor lock-in. That’s where the details of your package can mean you wind up reliant on particular services from a particular provider. This can make it technically and financially troublesome if you change your needs later on.
The other is uptime and access guarantee. Cloud services are no good if you can’t connect to them or if they go offline. Many providers will guarantee a maximum time during your contract in which your service is unavailable and compensate you if they breach this. You need to balance this guarantee against the service pricing, as well as making sure that any compensation will actually put things right. You should also check the provider’s record to see whether they’ve hit targets in the past.
Cloud Services for Business Scalability
One of the best reasons to use a cloud computing service is to ensure scalability. A small business can start on a small service plan and increase on demand with cloud services. Building in house infrastructure can be cheaper to start, but adding more servers laster can become a costly hassle.
Data storage is a big constraint that can affect your business’ ability to scale. The ability to house your servers and data offsite is beneficial for both security and reliability. Compounded by the ability to upgrade your servers and plans on the fly makes cloud computing services important for scalability.
It also provides benefits for employees that may work remotely or across different offices. Being able to access the same data no matter where you are working enables for more flexibile and productive operations. Cloud based software allows provides this flexibilty for businesses.
Summary of Service Models
Let’s recap what the different cloud computing services offer and who they suit.
Software as a Service takes care of almost everything. It’s best suited for businesses who need cloud technology to solve a business or customer need and don’t want to worry about making the solution work.
Platform as a Service balances the load between customer and provider. It’s best suited for businesses that want to develop their own tools but let the service provider take care of the underlying technology that makes them work.
Infrastructure as a Service puts more of the technical burden (or control) on the customer and largely takes care of the hardware. It’s best suited for businesses which want to control and develop their own technology and simply take advantage of the limited maintenance and efficient scalability that cloud computing offers.