At first, what does cloud computing do?

Well. It provides online data storage. It enables configuration and accessing of online applications. Apart from that, it provides a variety of software usage. And also it provides computing platform and computing infrastructure.

Now, that may not have lightened up what the meaning of cloud computing is, so here comes an example.

Here, using Gmail on my iPhone to check my emails. This is something that very commonly I would do. Well, one day I receive an email, and it has an attachment file that’s a Microsoft PowerPoint. Well, I think about it, and on my iPhone, I don’t have Microsoft Office or PowerPoint installed. Not even that, I don’t even have Windows OS installed on it. How am I going to use my phone to look at this PowerPoint attachment file? Well Google Drive services includes Google Docs, Sheets, and Slides. And this software packages are all inside the Google cloud, the Google Gmail server. And I can use these, the Google Docs, the Google Sheets and Slides to open up the attachment file and look at in. Even though my phone dose not have the Microsoft Windows OS, it dose not have the Microsoft Office and PowerPoint installed on it. But still, because I’m use the platform inside to look at these attachment files.

That’s what cloud computing is about. You can use the resources that you may not have on your device, but because you’re connected to the cloud that has these capabilities of software, platform, and computing infrastructure. So therefore, I just need connectivity, and it will do all the things that I need it to do, and send over the image so that I can use it as if everything is equipped on my mobile device.

Now just by reading to this, you can see that for smart devices, smartphones, in addition for new technology like internet of things, where these devices may not be fully equipped with all the software platform and infrastructure hardware that is needed. Well, cloud computing can provide magical power to it. And that’s why we’re going to study about the cloud computing.

What’s a cloud?

Well, a cloud can provide services through a public or private network, or the internet, which is the most common connection, where the services posting system is at a remote location. Cloud can support various applications such as email, web conferencing, games, database management, CRM which stands for Customer Relationship Management, and so many more.

Cloud models include public cloud, private cloud, hybrid cloud and a community cloud.

First let’s look more into the definitions of what these cloud are. The public cloud, this enables public systems and service access. Open architecture, such as email, are provided. This cloud be less secure due to its openness.

The next one is a private cloud, and it enables service access within an organization. Now, due to its limited in-organization characteristics, it may be more private in nature and therefore more secure.

Then, there is a community cloud, where a cloud accessible by a group of organizations that are formed, and that would be a community cloud.

Then we gave a hybrid cloud, this is a combination of a public cloud and a private cloud. The private cloud part would support critical activities. The public cloud will support non-critical activities to be accessed by various users flexibly.

Cloud service models

Now, first what I need to say is that as you can see on this picture there is SaaS, underneath it there is PaaS, and underneath it there is IaaS.

And these stand for SaaS, this stands for Software as a Service. The next one, PaaS, P-A-A-S, stands for Platform as a Service. The one at the bottom is IaaS, and this stands for Infrastructure as a Service.

The lower Service model supports the management, computing power, security of the upper service model. What this means is that IaaS supports PaaS and SaaS. Next, PaaS supports SaaS. And from SaaS, well, it is supported by both PaaS and IaaS.

And Those are the combination representative clouds models. A cloud client would use a web browser, mobile app, or some type of other client access feature to access one of these, or a combination of a couple of these.

Now let’s look into some more details.

Software as a Service provides a variety of software applications as a service to the end user.

The Platform as a Service provides a program executable platform for applications and development tools.

Infrastructure as a Service provides fundamental computing and security resources for the entire cloud. Backup storage, computing power, virtual machines these are the Infrastructure as a Service main domain.

Now, if you look at other papers and other definitions about cloud computing, you will see so many other type of combinations. For example, there are many other definitions that cloud be used. And to represent them all together, we could put just an X right here, where X stands for anything, anything as a service. And you can put in X your represented letter. For example, if you want to do a Network as a Service, then you use the N of network and you can call it a NaaS., N-A-A-S. Or, if you are talking about Database as a Service then you can use the D, the first letter of the database. Well, you can put it in here as DaaS, and that would be D-A-A-S, Database as a Service. You can do that for Business as a Service.

Now, however, when you go into the details of it, and based upon that three structure model which I had IaaS, PaaS, and SaaS on top. Well you can see that Network as a Service, NaaS, this one right here, this would fall into the gigger category of IaaS, Infrastructure as a Service, because networking is a part of the infrastructure. In addition, Database as a Service, DaaS right here. Database is considered a part of the platform services, so therefore DaaS can be seen as a part of PaaS that is provided, the Platform as a Service. So therefore you can use these terms or you can go with a general larger term, which was IaaS, PaaS and SaaS.

Cloud benefits

As you can see here, high efficiency, reliability, flexibility. In addition, applications as utilities over the Internet. You can manipulate and configure apps online. In addition, it is very cost-effective, and no software required, because all the software should be in the cloud.

Online development and deployment tools should be provided to you. In addition, on demand self service, meaning that when you need it, you go and request for this service. And when you request it, it should be provided to you on demand.

In addition, resource available on the network, this is the good part. But it does make sure that you have network connectivity, because you have to reach your cloud to receive the resources available on the cloud. So therefore, network dependent, cloud connectivity, and there you will be able to receive your resources.

Going into some of the characteristics, well, the essential characteristic is on demand self service. The common characteristics include broad networks access (广泛的网络访问), rapid elasticity (快速弹性), resource pooling (资源池), and measured services (测量服务). In addition, normally you can obtain massive scaling characteristics (大规模扩展), resilient computing support (弹性计算支持), and homogeneity (同质性). In addition, geographic distribution (地理分布), virtualization (虚拟化), service orientation (服务定位), low cost software (低成本的软件), and an advanced security (先进的安全特性) are the common characteristics.

The reading list below is recommended.

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