Hey Everyone, and welcome back. In today's video, we'll be discussing about the introduction to cloud computing. Now cloud computing has become one of the major buzzwords that you will see in any organizations that you're working with. Now, earlier, people used to assume that cloud computing would only impact the system administrators or the DevOps, guy, because it would change the way they provision the servers, it would change the way they do networking, etc. But that is not the right case. Cloud computing has not only impacted the system administrator, but it has also impacted the software developers. It has impacted the security engineers, the auditors and even the program managers. So recently I just got a call from one of my colleagues. He is a software developer. So he just said he said, can you just suggest a right but to do the cloud certification? Because in any organization that he is applying, everyone is having a mandate for a developer to have a knowledge about the cloud services. And he is actually going to start with this cloud certification just for that. And many of the cloud providers like AWS, they have a dedicated certification specifically for developers as well. So this basically tells on how much impact cloud computing has made into these organizations. So before we go ahead and understand more about what cloud computing is, it is necessary for us to step a little back and see what was there before cloud computing really came into a big picture. So let's go ahead and understand that data. So let's discuss about the use cases where that data center era was really prominent. Now, there is a requirement where your company wants to host a website. Now, typically, if you want to host a website, you will need a server. And within the organization, it is the responsibility of system administrator to take care of an entire server, provisioning, etc.. Now, system administrator will have a responsibility associated with this requirement, and he needs to arrange the following things. The first one is that he needs to choose either between a data center or hosting provider. Now, typically, if you go to the datacenter, you can either buy your own server or you can go ahead and rent a server which is being provided by the data center. In case if you are going with the hosting provider, you pay for the server on a monthly basis. So let me quickly show you this. So currently I am in my eBay and you see this is a physical server. So I still remember that time in my first organization, I used to work as a system administrator and we had a similar requirement there that a new website needs to be created. So the first thing that we went we went for shopping where we were discussing about, which is the right server that we needed to buy. And this, in fact, takes a lot of time. Now, this is one approach that you either buy this or you can even go ahead and rent the server from the data center also. Now, the second option is maybe you can go ahead with the hosting provider. So in the case of hosting provider, what do you basically do is you pay for the server on a monthly basis. So if you see this M.G. 256, it has a following specification and it starts from 365 dollars per month. So you basically pay on a monthly basis, OVH is typically one of the very famous providers for dedicated servers. And now also they have moved to cloud it. So it really says how impact the cloud computing is making everywhere. Now, after you decide that you are going for the server or you are going for the rent, the second part that typically used to happen was to send the inquiry. Now, typically, once you decide that you are going for the specific server or a specific datacenter, you would have to send the inquiry towards the datacenter on what would be the cost associated. Because if you typically look into the data center, a data center can have hundreds of thousands of servers. And it's not just you put the server within a stack, you need to have a networking part also, you need to have Internet connectivity. You need to have a proper cooling system so that your server do not get heat up. You need to have a proper power backup because if the power goes down, you server will go down and that will impact your website. And there are a lot of factors that are involved if you're hosting your server in a datacenter. So all of those inquiries about the requirements needs to be sent to the data center, how much power backup they have, what is the Internet connectivity they have? And once you come up with the data center that you want to go with, then comes the price negotiation. So this entire cycle used to take a lot of time. Now, one of the disadvantages of putting the server in data center is that if something goes wrong, you have to run and you have to see on what was the issue. So I still remember. During the first organization during the middle of the night, we just realized that the website has stopped working and we figured it out that there was some issue with this server. So we had to take a gap at the middle of the night, go to the data center, inspect the server, and we realized that there was an issue with the hardware chip related to memory. So we had to go to office, get a new memory stick, attach that memory, stick to the server, reboot it, and it started to work again. So that that is a big pain. And I really enjoy now because most of the organizations have now moved to cloud and all of these issues are being taken care of by the cloud service provider. Now in order to differentiate between the data center model and their cloud service provider model. Let's understand this with a simple example. Now, let's say that you do a big promotion. Your server capacity needs to be increased from 4 GB RAM to 32 GB RAM. Now, if you are in a data center, what you need to do is you have to buy a 32 GB ram stick from eBay or Amazon or whatever contacts you have, go to the data center and install that RAM stick within your server. So that is the first way. In the hosting provider. Let's say that you're going with OVH, you need to typically raise a support ticket and you can expect a response time of 15 minutes to 12 hours for them to respond. And then you get the datacenter guys to resize your server depending on the requirement that you have. And in cloud with all you do is you stop this and you change the instance size. This takes less than one minute or close to two minutes to do that. So let me quickly show you this. So I'm in my AWS management and you see I have one server which is present, which is kplabs-demo-01 Now, this server is of type t2.micro, which basically means that this has 1 GB of RAM Now If I want to change this size, let's say I want a 64 GB RAM or even a 256 GB RAM All I have to do is I have to go to actions, go to instance's settings, change instance type and here I can just select which instance type I want. So if you typically see this specific instance type, which is r5.24xlarge, this is like a 768 GB RAM. And as soon as I click on apply, my server will be changed from 1 GB RAM to 768 GB RAM within just less than one minute. And this is the true power of cloud computing. And this is the exact reason why a lot of organizations are now moving to the cloud computing. Now going by the definition terms, cloud computing is a model in which computing resources are available as a service. Now, in order to understand cloud computing, there are three important characteristics that you need to understand of a typical cloud service provider. Now, the first one is on demand and self-service. What this basically means is that a customers should be able to launch things without a manual intervention. Not typically. If you look into the older approach where you have a hosting provider and you want to change the instance type of a dedicated server, you have to raise the ticket to the team and they will respond maybe in 15 minutes or 12 hours, or if it is a weekend, they'll respond after 24 hours. So here manual intervention is required. So within cloud computing, the first characteristic states that it should be self service. Like if I want to increase on 1 GB RAM to 30 GB RAM or two 700 GB RAM, I should be able to do it at my time without any manual intervention. And this is something that we already saw in in our AWS console. Like if I wanted to change the instance type, I could do it right now. The second important characteristic of a cloud computing provider is elasticity. That basically states that you can scale up and you can scale down anytime. So this is a very important characteristic and basically it also impacts your cost. So we were discussing about the use case where there is a big promotion. So what is basically means that a promotion might last for 24 hours. So what you might want to have is during the 24 hours, you want to increase the capacity of your servers and after 24 hours completes and your promotion is over, you can scale down to the normal traffic. So that is also for as elasticity and 3rd is measured service. Measured service. basically states you should pay for what you use. So if you use a 256 GB ram server for ten hours, then you should only pay for that 10 hours and nothing more. Now, typically specifically for OVH I still remember that you have. just pay 365 dollars per month outright, even if you just keep your server in a shut-down state for half a month, you still will have to pay full 365 dollars per month. And this does not really constrain the measured service. You're not paying for what you use. In terms of AWS. If my server is stopped, then my billing will also stop. Then I don't have to pay for the server which are in the stopped condition I only pay for what I use over here. So along with that, AWS is not the only cloud service provider. In fact, there are a lot of other cloud service providers which are available and any cloud service provider who are providing the cloud computing services, they have to adhere to this important characteristics, which is on demand elasticity and measure service. So one of the other very famous cloud providers is Digital Ocean. And in fact, this is one of my favorite cloud service providers. Now, if you typically look into the pricing here, for 1GB RAM, 1 vCPU, 25 GB SSD disk, you pay five dollars per month or you pay 0.007 dollars per hour. So basically you are paying at a hourly basis. So let's say that you use this specific server for 10 hours after which you terminate it So you will only pay for that 10 hours. You will not pay for the entire month. And this is what the major service is all about. So this is the high level overview about the introduction to cloud computing. Again, we'll be discussing more in detail in the upcoming videos. But for this video, I hope the high level introduction has been understood by you. And if you have any doubts, questions, suggestions, feel free to connect us at Twitter, Facebook or LinkedIn or email us at email@example.com Thanks for watching.