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Cloud computing is by far one of the hottest topics in today's IT world. Basically, cloud computing can provide virtualized processing, storage, and computing resources to users remotely, making the resources transparently available regardless of the user connection. To put it simply, some people just refer to the cloud as “someone else's hard drive.” This is true, of course, but the cloud is much more than just storage.

The history of the consolidation and virtualization of our servers tells us that this has become the de facto way of implementing servers because of basic resource efficiency. Two physical servers will use twice the amount of electricity as one server, but through virtualization, one physical server can host two virtual machines, hence the main thrust toward virtualization. With it, network components can simply be shared more efficiently.

Users connecting to a cloud provider's network, whether it be for storage or applications, really don't care about the underlying infrastructure because as computing becomes a service rather than a product, it's then considered an on-demand resource, described in Figure 1.7.

Figure 1.7 Cloud computing is on-demand

Centralization/consolidation of resources, automation of services, virtualization, and standardization are just a few of the big benefits cloud services offer. Let's take a look in Figure 1.8.

Figure 1.8 Advantages of cloud computing

Traffic Path to Internal and External Cloud Services

Centralization/consolidation of resources, automation of services, virtualization, and standardization are just a few of the big benefits cloud services offer as shown in Figure 1.8.

Cloud computing has several advantages over the traditional use of computer resources. Following are advantages to the provider and to the cloud user.

Here are the advantages to a cloud service builder or provider:

■ Cost reduction, standardization, and automation

■ High utilization through virtualized, shared resources

■ Easier administration

■ Fall-in-place operations model

Here are the advantages to cloud users:

■ On-demand, self-service resource provisioning

■ Fast deployment cycles

■ Cost effective

■ Centralized appearance of resources

■ Highly available, horizontally scaled application architectures

■ No local backups

Virtual Services

Cloud providers can offer you different available resources based on your needs and budget. You can choose just a vitalized network platform or go all in with the network, OS, and application resources.

Figure 1.9 shows the three service models available depending on the type of service you choose to get from a cloud.

Figure 1.9 Cloud computing service

You can see that IaaS allows the customer to manage most of the network, whereas SaaS doesn't allow any management by the customer, and PaaS is somewhere in the middle of the two. Clearly, choices can be cost driven, so the most important thing is that the customer pays only for the services or infrastructure they use.

Let's take a look at each service:

Infrastructure as a Service (IaaS): Provides only the network Delivers computer infrastructure – a platform virtualization environment – where the customer has the most control and management capability.

Platform as a Service (PaaS): Provides the operating system and the network Delivers a computing platform and solution stack, allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an application. An example is Windows Azure.

Software as a Service (SaaS): Provides the required software, operating system, and network SaaS is common application software such as databases, web servers, and email software that's hosted by the SaaS vendor. The customer accesses this software over the Internet. Instead of having users install software on their computers or servers, the SaaS vendor owns the software and runs it on computers in its data center. Microsoft Office 365 and many Amazon Web Services (AWS) offerings are perfect examples of SaaS.

So depending on your business requirements and budget, cloud service providers market a very broad offering of cloud computing products from highly specialized offerings to a large selection of services.

What's nice here is that you're is offered a fixed price for each service that you use, which allows you to easily budget wisely for the future. It's true – at first, you'll have to spend a little cash on staff training, but with automation you can do more with less staff because administration will be easier and less complex. All of this works to free up the company resources to work on new business requirements and be more agile and innovative in the long run.

Basic Virtual Network Infrastructure

Having centralized resources is critical for today's workforce. For example, if you have your documents stored locally on your laptop and your laptop gets stolen, you're pretty much screwed unless you're doing constant local backups. That is so 2005!

After I lost my laptop and all the files for the book I was writing at the time, I swore (yes, I did that too) to never have my files stored locally again. I started using only Google Drive, OneDrive, and Dropbox for all my files, and they became my best backup friends. If I lose my laptop now, I just need to log in from any computer from anywhere to my service provider's logical drives and presto, I have all my files again. This is clearly a simple example of using cloud computing, specifically SaaS, and it's wonderful!

So cloud computing provides for the sharing of resources, lower cost operations passed to the cloud consumer, computing scaling, and the ability to dynamically add new servers without going through the procurement and deployment process.

Exam Essentials

Understand basic cloud technology. Understand cloud services such as SaaS and others and how virtualization works.