What is cloud computing?

At a high level, cloud computing is the on-demand availability of IT resources such as servers, storage, databases, and so on over the web, without the hassle of managing physical infrastructure. The best way to understand the cloud is to take the electricity supply analogy. To get light in your house, you just flip a switch on, and electric bulbs light up your home. In this case, you only pay for your electricity use when you need it; when you switch off electric appliances, you do not pay anything. Now, imagine if you needed to power a couple of appliances, and for that, you had to set up an entire powerhouse. It would be costly, right? It would involve the costs of maintaining the turbine and generator and building the whole infrastructure. Utility companies make your job easier by supplying electricity in the quantity you need. They maintain the entire infrastructure to generate electricity and they can keep costs down by distributing electricity to millions of houses, which helps them benefit from mass utilization. Here, the utility companies represent cloud providers such as AWS, and the electricity represents the IT infrastructure available in the cloud.

While consuming cloud resources, you pay for IT infrastructure such as computing, storage, databases, networking, software, machine learning, and analytics in a pay-as-you-go model. Here, public clouds like AWS do the heavy lifting to maintain IT infrastructure and provide you with on-demand access over the internet under a pay-as-you-go model. As you generally only pay for the time and services you use, most cloud providers can provide massive scalability, making it easy to scale services up and down. Where, traditionally, you would have to maintain your servers all by yourself on-premise to run your organization, now you can offload that to the public cloud and focus on your core business. For example, Capital One's core business is banking and it does not run a large data center.

As much as we tried to nail it down, this is still a pretty broad definition. For example, we specified that the cloud can offer software, that's a pretty general term. Does the term software in our definition include the following?

• Video conferencing
• Virtual desktops
• Email services
• Contact center
• Document management

These are just a few examples of what may or may not be included as available services in a cloud environment. When AWS started, it only offered a few core services, such as compute (Amazon EC2) and basic storage (Amazon S3). AWS has continually expanded its services to support virtually any cloud workload. As of 2022, it has more than 200 fully featured services for computing, storage, databases, networking, analytics, machine learning, artificial intelligence, Internet of Things, mobile, security, hybrid, virtual and augmented reality, media, application development, and deployment. As a fun fact, as of 2021, Amazon Elastic Cloud Compute (EC2) alone offers over 475 types of compute instances.

For the individual examples given here, AWS offers the following:

• Video conferencing  – Amazon Chime
• Virtual desktops – AWS WorkSpaces
• Email services – Amazon WorkMail
• Contact Center – Amazon Connect
• Document Management – Amazon WorkDocs

Not all cloud services are highly intertwined with their cloud ecosystems. Take these scenarios, for example:

• Your firm may be using AWS services for many purposes, but they may be using WebEx, Microsoft Teams, Zoom, or Slack for their video conference needs instead of Amazon Chime. These services have little dependency on other underlying core infrastructure cloud services.
• You may be using Amazon SageMaker for artificial intelligence and machine learning projects, but you may be using the TensorFlow package in Sagemaker as your development kernel, even though Google maintains TensorFlow.
• If you are using Amazon RDS and choose MySQL as your database engine, you should not have too much trouble porting your data and schemas over to another cloud provider that supports MySQL if you decide to switch over.

However, it will be a lot more difficult to switch to some other services. Here are some examples:

• Amazon DynamoDB is a NoSQL proprietary database only offered by AWS. If you want to switch to another NoSQL database, porting it may not be a simple exercise.
• Suppose you are using CloudFormation to define and create your infrastructure. In that case, it will be difficult, if not impossible, to use your CloudFormation templates to create infrastructure in other cloud provider environments. Suppose the portability of your infrastructure scripts is important to you, and you are planning on switching cloud providers. In that case, using Ansible, Chef, or Puppet may be a better alternative.
• Suppose you have a streaming data requirement and use Amazon Kinesis Data Streams. You may have difficulty porting out of Amazon Kinesis since the configuration and storing mechanism are quite dissimilar if you decide to use another streaming data service like Kafka.

As far as we have come in the last 15 years with cloud technologies, I think vendors realize that these are the beginning innings, and locking customers in right now while they are still deciding who their vendor should be will be a lot easier than trying to do so after they pick a competitor.

However, looking at a cloud-agnostic strategy has its pros and cons. You want to distribute your workload between cloud providers to have competitive pricing and keep your options open like in the old days. But each cloud has different networking needs, and connecting distributed workloads between clouds to communicate with each other is a complex task. Also, each major cloud provider, like AWS, Azure, and GCP, has a breadth of services, and building a workforce with all three skill sets is another challenge.

Finally, clouds like AWS provide economy of scale, which means the more you use, the more the price goes down, which may not benefit you if you choose multi-cloud. Again, it doesn't mean you cannot choose a multi-cloud strategy, but you have to think about logical workload isolation. It would not be wise to run the application layer in one cloud and the database layer in other, but you can think about logical isolation like running the analytics workload and application workload in a separate cloud.

In this section, you learned about cloud computing at a very high level. Let’s learn about the difference between the public and private clouds.

What is AWS (Amazon Web Services)?

Amazon Web Services (AWS) is the world’s most broadly adopted cloud platform, offering over 200 fully-featured services from data centers globally. Even though there are a few worthy competitors, it doesn't seem like anyone will push them off the podium for a while.

For example, it’s difficult to catch up with AWS’ pace of innovation. AWS services and features have grown exponentially every year: as shown in the following figure, in 2011, AWS released over 80 new significant services and features, followed by nearly 160 in 2012; 280 in 2013; 516 in 2014; 722 in 2015; 1,017 in 2016; 1,430 in 2017; and 1,957 in 2018; 2,345 in 2019, 2,757 in 2020, and 3,084 in 2021:

There is no doubt that the number of offerings will continue to grow at a similar rate for the foreseeable future. Gartner named AWS as a leader for the 11th consecutive year in the 2021 Gartner Magic Quadrant for Cloud Infrastructure & Platform Services. AWS is innovating fast, especially in new areas such as machine learning and artificial intelligence, the Internet of Things (IoT), serverless computing, blockchain, and even quantum computing.

The following are some of the key differentiators for AWS in a nutshell:

It’s not always possible to move all workloads into the cloud, and for that purpose, AWS provides a broad set of hybrid capabilities in the areas of networking, data, access, management, and application services. For example, VMware Cloud on AWS allows customers to seamlessly run existing VMware workloads on AWS with the skills and toolsets they already have without additional hardware investment. If you want to run your workload on-premise, then AWS Outposts brings native AWS services, infrastructure, and operating models to virtually any data center, co-location space, or on-premises facility. You will learn more details about hybrid cloud services later in this book.

This is just a small sample of the many AWS services that you will see throughout this book. Let's delve a little deeper into how influential AWS currently is and how influential it has the potential to become.