‫So now let's talk about cloud computing.
‫So what is cloud computing?
‫The definition is as such,
‫cloud computing is the on-demand delivery of compute power,
‫database storage, application, and other IT resources.
‫The very important keyword here is on-demand,
‫you get it when you need it.
‫And then through a cloud service platform,
‫you're going to get a pay-as-you-go pricing.
‫That means that you're only going to pay
‫for what you requested when you requested it
‫and as you're using it, when you're done using it,
‫you're not going to pay anymore.
‫This is a big shift, right?
‫Then this is cloud computing.
‫So we can provision exactly the right type
‫and size of computing resources you need.
‫Do you need a big server? We have that for you.
‫Do you want a small one? We have that too.
‫Do you want 10? Yes.
‫Do you want two tomorrow? Of course.
‫The cloud really allows you to adapt
‫to the type and size you need.
‫Then you can access all these resources,
‫not with 24-hour notice, not with two hours notice,
‫but instantly, you don't need to order things in advance.
‫When you want a server, and you'll see this in this course,
‫you'll have it within seconds.
‫Then the cloud will also give you a really nice interface
‫so you can easily access your servers, your storage,
‫databases, and a set of application services.
‫Something about the cloud, but in specific AWS,
‫which is Amazon Web Services owns and maintains
‫the network-connected hardware required
‫for these application services while you provision and use
‫what you need via a web application.
‫So with this interface,
‫we'll make all these things a reality.
‫Now, let's go back to our traditional IT.
‫So we're changing.
‫We have our office or our garage,
‫but now instead of building our own data center
‫we're going to use the cloud, and in the cloud,
‫which is also a data center, is just not our data center,
‫we're going to have servers one, two, three, as we need
‫and as we go and we're just going to pay for exactly
‫what we're using.
‫So you have actually been using the cloud without
‫even knowing it because it is omnipresent,
‫but not necessarily visible.
‫So if you use a web client such as Gmail,
‫well, for example, it's an email cloud service
‫and you're going to pay only for the emails you stored.
‫You're not provisioning servers when you use Gmail,
‫you just use it.
‫Maybe you've stored some data on the cloud,
‫maybe through Dropbox, Google Drive, Google Photos,
‫iCloud, I don't know.
‫But with Dropbox, for example, it's a cloud store service,
‫you're going to put your files on Dropbox.
‫And originally, fun fact, Dropbox was built on AWS.
‫So we've been using a cloud storage service as well
‫without knowing it.
‫And Netflix, it's huge.
‫It is built entirely on AWS and it provides you
‫a cloud service, which is to get video on-demand.
‫Now, obviously these cloud services are very different
‫from AWS, but we'll learn what it goes behind these services
‫and how AWS can help you build
‫these kinds of cloud services.
‫So let's go one step further.
‫There are different kinds of clouds out there.
‫The first one is called a private cloud and the provider is,
‫could be Rackspace.
‫This is cloud services used by a single organization,
‫they're not exposed to the public,
‫so you get your own private cloud,
‫your own private data center,
‫it's just managed by someone else.
‫You still have complete control over it
‫and you have more security for a sensitive application,
‫which may need some specific business needs.
‫This is out of scope for this course,
‫but still good to mention.
‫Now the public cloud is more interesting.
‫So three famous cloud providers that are public,
‫are Microsoft Azure, Google Cloud, and Amazon Web Services
‫that we'll be learning in this course, obviously.
‫So in this case, the cloud resources own and operated
‫by a third party cloud service provider
‫and they're delivered over the Internet
‫and we'll see the six advantages of using cloud computing.
‫So in this instance, that means that from AWS,
‫we'll be able to request what we need when we want it.
‫And then lastly, which is also important for the exam
‫is the concept of a hybrid cloud.
‫So with hybrid, we're actually getting the mix
‫of private and public.
‫We're going to keep some servers on premises and we'll
‫extend some of the capabilities we need into the cloud.
‫That means that we'll have a hybrid of our own
‫infrastructure and the AWS cloud.
‫We'll have control over sensitive assets
‫in your private infrastructure,
‫but we'll have the flexibility and the cost effectiveness
‫of using the public cloud.
‫Now, five characteristics of cloud computing.
‫The first one is that it's fully on-demand and self service.
‫Users, and we'll see this in this course,
‫we will be able to provision resources
‫and use them without having anyone from AWS intervene.
‫Then we'll be having access to a broad network,
‫the resources will be available over the network,
‫and it can be accessed in diverse ways
‫as we'll see in this course.
‫It'll be multi-tenancy and we'll have resource pooling.
‫So that means that not just us, but other customers
‫from AWS can share the same infrastructure
‫and applications while still having security and privacy.
‫And then these multiple customers are getting serviced
‫from the same physical resources.
‫So here, me, you, and other customers,
‫we're going to share this entire data center of the cloud.
‫This gives us rapid elasticity and scalability.
‫That means that we can automatically and quickly acquire
‫and dispose resources when we need.
‫And that means that we can quickly
‫and easily scale based on demand.
‫And that is a major advantage of the cloud.
‫Finally, it's a measured service, so the usage is going
‫to be measured and we're going to pay exactly
‫for what we have used.
‫This is a big shift from on premises.
‫Now, six advantages.
‫We're going to trade capital expenses
‫for operational expenses, so CAPEX or OPEX.
‫That means that you don't own hardware,
‫you're going to pay on-demand and that will reduce
‫your total cost of ownership, your TCO,
‫and your operational expense.
‫That means that you don't buy the hardware in advance,
‫you're just going to rent it from AWS.
‫Then we're going to benefit from massive economies of scale.
‫The price is because we are using AWS, not just us,
‫but other customers and so many people are using it,
‫then the prices will be reduced by AWS over time because AWS
‫will be more efficient at running due to its large scale.
‫We also need to stop guessing capacity.
‫Before we had to plan and buy servers in advance
‫and hope that it would meet the capacity,
‫but now we can actually scale automatically
‫based on the actual measured usage for our application.
‫And because everything's on-demand,
‫we have increased speed and agility.
‫We can create, operate and do stuff right away,
‫no blockers for us to be efficient.
‫And finally, we have a huge cost that we don't need
‫to have anymore, which is we can stop spending money running
‫and maintaining data centers.
‫And this allows a team of say five people
‫to create a global application in minutes,
‫thanks to leveraging this AWS global infrastructure
‫that is going to be worldwide.
‫Okay. So the problems we've just solved by using the cloud
‫is that we're more flexible, we're more cost effective,
‫we are more scalable because we can add resources
‫as we need to go along,
‫we're elastic, we can scale out and scale-in when needed,
‫we also have high availability and fault tolerance
‫because we don't really on the one data center,
‫we rely on the fleet of data centers all around the world.
‫We're more agile, we can rapidly develop,
‫test and launch software applications,
‫and although this make the cloud a really no brainer.
‫So that's it, just for an introduction of how the cloud
‫is going to be effective.
‫Now in the next lecture,
‫we're going to view one step further,
‫what are the different types of cloud computing.