What is Infrastructure-as-a-Service and do I need it? Part 1

IaaS certainly is an ugly bit of jargon, but what about the business benefits it offers to organisations of all types and sizes? And what about the risks? In this first part of a two-part blog series, we set out exactly what Infrastructure-as-a-Service is, what’s included and how it differs from other cloud computing approaches. 

What exactly is Infrastructure-as-a-Service?

Infrastructure-as-a-Service (IaaS) is the most basic kind of cloud computing that organisations use today. It lets you consume IT without putting up the investment or learning the skills associated with buying and running large, complex IT equipment in-house. 

Substitute the word ‘Infrastructure’ for ‘Hardware’ and you get the picture. 

By hardware, we mean the fundamentals of your IT environment: the server processing power, the networking, the storage… Before cloud computing every business needed to own and operate this stuff themselves, or host it in a third-party datacentre somewhere. Now it can be used like any other utility, and paid for by the unit.

What does IaaS include?

IaaS is the foundational piece of cloud computing, and deals with everything at the ground level that other IT systems build on top of. 

IaaS is distinct from Platform of a Service (PaaS) and Software as a Service (SaaS); the two other forms of cloud computing that take on more of the IT stack. 

The dividing line between IaaS and its cloud cousins is where physical infrastructure components end and software begins.

IaaS is principally raw compute power and storage capacity plus the bits and pieces that enable data to enter, move around and leave that environment, like switches and load balancers. It’s ideal for those who know what they need from such bottomless resources, and prefer the idea of paying for it an incremental cost basis rather than investing to own it themselves. All you need to do is connect to it.

What don’t you get with IaaS?

The more you add to this basic IaaS model, the more it deviates higher up the food chain toward PaaS. PaaS is essentially IaaS with some other IT services and capabilities thrown in.  These might include:

  • Operating systems
  • Development environments and tools
  • Or anything ‘above’ this, like software applications

IaaS doesn’t give you any software; not even basic operating systems. This is to give IaaS users the maximum flexibility over what they want to run. It also enables IaaS providers to keep things simple, and keep costs to a minimum. PaaS is typically offered as a development engine for software developers, with PaaS provider delivering the IaaS fundamentals plus the necessary software and its ongoing license support.

A useful lasagne analogy

Four families decide to have lasagne for their evening meal.

Family A

The first family live off the land and make their lasagne from scratch. Everything from growing the vegetables to rearing the beef and eggs goes into the finished dish. This example represents the on-premise IT model (i.e. non-cloud IT).

Family B

The second family have bought a frozen lasagne. The basic ingredients have been assembled in the right quantities, the beef ground and the pasta made, but not actually cooked. It’s faster and much less effort than Family A, plus they only pay for one meal at a time rather than bear all those overheads. However, like Family A, the heating up of the lasagne, laying the table, assembling a side salad and putting on some drinks all need to be added to the process to produce the desired result. This example represents the IaaS model.

Family C

The third family are much like the second, but they aren’t going to do any cooking at all. They’ve ordered a takeaway and the lasagne will be arriving soon, along with one or two sides. It costs a bit more but all that’s left to do themselves is lay the table, open a bottle or two or wine and clear it all up afterwards. This example represents the PaaS model.

Family D

The fourth family provide nothing to the meal-making. They are just consumers, but this means they pay the highest premium. Their lasagne is at the restaurant waiting to be prepared to order.  All they have to do is turn up, eat and pay. This example represents the SaaS model.

Stay tuned for part two in this two-part blog series on IaaS, where we’ll be looking at the market landscape for this technology, as well as the benefits, costs and everything else you might need to know to decide your first move.