Understanding cloud computing
What do we mean when we talk about cloud from an information technology perspective? People mention cloud services; where do we get the services from? What services are offered?
The Wikipedia definition of cloud computing is as follows:
"Cloud computing is a computing term or metaphor that evolved in the late 1990s, based on utility and consumption of computer resources. Cloud computing involves application systems which are executed within the cloud and operated through internet enabled devices. Purely cloud computing does not rely on the use of cloud storage as it will be removed upon users download action. Clouds can be classified as public, private and [hybrid cloud|hybrid]."
If you have worked with virtualization, then the concept of cloud is not completely alien to you. With virtualization, you can group a bunch of powerful hardware together, using a hypervisor. A hypervisor is a kind of software, operating system, or firmware that allows you to run virtual machines. Some of the popular Hypervisors on the market are VMware ESX or Microsoft's Hyper-V. Then, you can use this powerful hardware to run a set of virtual servers or guests. The guests share the resources of the host in order to execute and provide the services and computing resources of your IT department. The IT department takes care of everything from maintaining the hypervisor hosts to managing and maintaining the virtual servers and guests. The internal IT department does all the work. This is sometimes termed as a private cloud.
Third-party suppliers, such as Microsoft, VMware, and Amazon, have a public cloud offering. With a public cloud, some computing services are provided to you on the Internet, and you can pay for what you use, which is like a utility bill. For example, let's take the utilities you use at home. This model can be really useful for start-up business that might not have an accurate demand forecast for their services, or the demand may change very quickly. Cloud computing can also be very useful for established businesses, who would like to make use of the elastic billing model. The more services you consume, the more you pay when you get billed at the end of the month. There are various types of public cloud offerings and services from a number of different providers. The TechNet top ten cloud providers are as follows:
- VMware
- Microsoft
- Bluelock
- Citrix
- Joyent
- Terrmark
- Salesforce.com
- Century Link
- RackSpace
- Amazon Web Services
It is interesting to read that in 2013, Microsoft was only listed ninth in the list. With a new CEO, Microsoft has taken a new direction and put its Azure cloud offering at the heart of the business model. To quote one TechNet 2014 attendee:
"TechNet this year was all about Azure, even the on premises stuff was built on the Azure model"
With a different direction, it seems pretty clear that Microsoft is investing heavily in its cloud offering, and this will be further enhanced with further investment. This will allow a hybrid cloud environment, a combination of on-premises and public cloud, to be combined to offer organizations that ultimate flexibility when it comes to consuming IT resources.