“Nobody can tell me what the Cloud actually is” – a direct quote from a conversation I overheard whilst on the train this week.
Not an uncommon view-point it seems and, as Daryl Vogan correctly pointed out when I tweeted about this, it is definitely true for anybody outside of the tech bubble I live in.
So it got me thinking. What is the Cloud? And can we define ‘the Cloud’ in English? Yes is the answer and it comes in two parts:
- What is the Cloud for the consumer?
- What is the Cloud for the enterprise?
For the consumer
The consumer Cloud is nothing new. In fact it has been around for a long time. If you have a personal email address like Gmail or Hotmail then you are a Cloud user. In this case it is a service we as consumers use that is run by and managed by a service provider.
The only change we have been witness to over the last few years is the sheer number of Cloud services we use daily. This has been caused by the migration of traditional local applications to the Cloud. A good example is processing programmes (e.g. Microsoft Word) being offered via the Cloud in the form of Google Docs or Office 365 where everything is based online from the application right through to the file storage.
The enterprise Cloud is slightly different in that it is a far newer concept…or at least that is what they want you to think! I would argue that rather than being something new, what we are seeing is a maturing of Cloud offerings to the extent that they are fit for purpose within the enterprise.
Once you delve a little deeper into the enterprise Cloud, you will find a little more complexity than with its consumer-focused cousin. At a high level, there are two distinct types of Cloud, as well as three main Cloud-service types. I’m going to start by examining the service types, all of which end with the phrase “as a service”. I’m really starting to think that somebody somewhere is being paid per term they can apply the words “as a service” to as there is an ever-growing list of them. For me, the main three are:
1) Software as a Service (SaaS)
This is the providing of applications/software to users through the internet usually on a subscription basis. Examples include email (Gmail), productivity suites (Office 365) and enterprise apps (SAP’s Cloud for Customer).
2) Platform as a Service (PaaS)
This is the providing of a deployment/development platform through the internet where applications can be deployed/created. PaaS can form the basis of a SaaS offering. Good examples here include the SAP HANA Cloud Platform (HCP) or Google’s App’s platform. In PaaS the lowest level of access you usually have is the development platform software. You cannot access the operating system level.
3) Infrastructure as a Service (IaaS)
This is the providing of OS-level infrastructure. In an IaaS scenario the subscriber manages everything from the operating system level up (installing software etc.) but the responsibility of the underlying hardware management resides with the service provider. Examples include Amazon’s AWS or VMWare’s vCloud. These services are provided from a Cloud and there are two main cloud types:
The public cloud
The Public cloud is where one or more of the service offerings described previously are made available, but that same offering is shared between many subscribers. For example, an application such as email in a public cloud would be shared amongst multiple subscribers. The fact that the data for these subscribers resides on the same server would be completely transparent. This is known as multi-tenant environment and has advantages such as shared infrastructure and single application platforms and therefore is usually lower cost
The private cloud
The private cloud is slightly different and is better equated to an on-premise solution rather than the public cloud. The main difference is that the private cloud is usually based on non-shared resources. So in the case of an email server, instead of sharing your sever with multiple subscribers, it would be dedicated to a single subscriber (single-tenant environment). As there is clearly more effort and resources involved in a private cloud it is normally more expensive.
In a nutshell
If I’m perfectly honest, Gareth Ryan’s response to my tweet summed it up very well – “There is no cloud. Just other people’s computers”.
Really speaking whether you are talking about IaaS, PaaS or SaaS, that is all it is – somebody else is hosting and managing your content and services for you. The only other difference is that you now access that content and services over the internet rather than through other more localised means.
The Cloud elevator explanation can be boiled down to one sentence for both consumer and the enterprise:
The Cloud is the providing of free and paid-for internet-based applications and services to subscribers.
Consumer examples (mostly S/PaaS)
- Personal Email like Gmail, Hotmail and Yahoo mail,
- File storage like Dropbox, Google Drive and Microsoft’s One Drive,
- Social Networking like Facebook, LinkedIn and Twitter
- IaaS: Amazon AWS, Microsoft Azure and VMWare’s vCloud.
- PaaS: SAP’s HANA Cloud Platform, Google’s Apps platform or Microsoft Azure
- SaaS: SAP’s Cloud for Customer, Microsoft’s Office 365 or Citrix Join.me