In this video, you will learn to define Cloud Computing and Cloud Computing Models. Now, we're going to talk about what is Cloud computing. We talk about how we end up from just restoration to have entire Cloud environments, but what is a Cloud computing? Cloud computing is an on-demand availability of system resources. So this means that you will have an environment that has virtualized devices that will serve a business purpose. This could be anywhere from storage up to compute empower. The chart you have on your screen, you will see some of the positives and negatives of Cloud computing. Now I have to say that some of the negatives are just perceptions, there are facts that could contradict those but anyways. So let's give it a plus side. So you have choice and an agility of business. Since you have several virtualized resources, you have flexibility, you can grow in any place around the world, you have integration, that's what it means. You have a scale and cost. So as you may think having virtualized resources, sometimes is cheaper than having boxes for each individual server, or servers you want to deliver. Obviously this allow us to scale the business as we need. Since we don't need to add hardware to the solution, we can pay our provider to have more resources as we're drawing. Then we have encapsulated change management. So this means that the whole management of the system, regardless of how big or how small it is, we can have the single place where we can manage everything. We don't need to be on side of Indian one day, and we don't need to be on the side of the United States, and the other day to be able to manage it, there should be a single point or single place where you can manage all the environment. Of course as technology moves on, Cloud moves on as well. That means that we will have next generation architecture, every new single technology out there that will be implemented in Clouds, and will make it more effective and more efficient, providers usually apply those technologies to the service, making it better day to day. Now, let's start to the negatives. So there's a perception out there that since you're sharing resources with other people, security gets compromised. This is not true, but I can see how that perception can fly. So for example, let us talk about an email service. Now let's talk about gmail, for example. So you have different accounts, or hosted within the same physical resources, or the same Cloud environment. So there are countermeasures and there are things and elements that you need to consider for Cloud computing, that usually these big companies and providers gave us. We will cover that a little bit later in this session, but it is in fact a perception that security could be not that proper within a Cloud computing environment. Now the other thing is to lock in, and this is actually true. By locking, we mean that if you have a provider, and if you have a whole service based in the Cloud, and you hired up a Cloud provider to do this, usually that takes a lot of work. So this means that if this provider, out of the blue decides to apprise their fees or the fees that you're paying, you might be hard to move away from that provider, depending on how much services you have, and how much time you have invested. So this could be a drawback for Cloud computing. Of course, if this is properly planned, you can do some maintenance and movements to be able to move provider. It's not that you cannot do that, but definitely it requires some work. Now, lot of control, lack of control. So this means that people have the perception that probably since you don't have the devices onsite, you're not really controlling them, it's proven that's not the case for argue. Even though you hire the service, you still have control. Now dependent on services that you're having, this is something that we will cover later on. You might not be responsible of doing patching activities, for example, or providing maintenance to the devices because you're not managing them. So you could have lack of control for sure, and also the reliability, and we go back to the same point as, you don't have control of the devices, how can I rely on something that I don't control, but it is part of the Cloud computing environment. Now let's talk about the different Cloud computing types that you can have out there. So the first one being the public Cloud. So a public Cloud is the most common type of Cloud computing you can find out there, pretty much it's owned and operated by a third party. So you don't need to do pretty much anything other than provide instructions, and how do you want to manage it. You share hardware and processing resources with other organizations, and this is usually called a tenant. So this means that there's a group of physical resources that is assigned to serve different customers. So you can be sharing those resources with another company, that's what is called a public Cloud. Of course, you didn't need to purchase anything, everything is provided by the carrier, which that used to lower the costs, you don't need to provide maintenance, and you can scale the environment as much as you like, and it is very reliable, hence being one of the most common options for companies. Now, let's talk about the other type or the second type, which is a private Cloud. This comes when you're talking about security. What if I don't really want to share those resources with another company? So this is going to be the option for you. So on private Cloud you really need to share resources, you need to dedicate resources for your Cloud. So this means that you're not going to be part of a tenant anymore, but you're going to have dedicated resources. This allows you for more flexibility to meet specific business needs. So if there's a portion of your business that is critical, that you don't really want to have the risk of sharing physical resources with other organizations, you can have or you can achieve those by having a private Cloud. This allows more security because you will have higher level of controls, meaning that again, you want to share anything with anyone. So you could have a bit more of control of what you have on your private Cloud. Now, as you will think, the third option is going to be a hybrid Cloud. Where you pretty much going to have the best of both worlds. You can control your private infrastructure for sensitive assets, it's cost effective, because obviously is going to be cheaper to grow in the public side than in a private side, because private are going to be resources dedicated to you, hence they are going to be expensive. So on a hybrid Cloud option, if you have a portion of your business that is going to grow, you can make grow in the public side or in the public Cloud, and that is going to be cheaper than growing the whole private thing. So it can get cost-effective there. Now let's talk about the Cloud Computing Reference Model. This is just an abstract chart that describes the functions of a Cloud computing environment. Is just the reference to understand how the Cloud computing works. Right on your left you have the consumer, which will be the person hiring the service, or implementing in service. The security side is managed by a figure of a Cloud auditor, it's going to make sure that the security is the proper one, but the privacy is there and off course doing control audits to make sure that the information is reliable, and it is in good hands. The big box in the middle is the Cloud Provider, which will provide different services, which might be Software as a Service, Platform as a Service, and Infrastructure as a Service, we will cover those in the next slide. At the right, you have the Cloud Broker, which is the people who are in a way reselling the services of the Cloud to Cloud Consumers. At the bottom, you can see the Cloud Carrier, which is the organization who's actually managing the Cloud, and doing patching of the systems, and maintaining everything in order for the service to be effective. Now, let's talk about the models of Cloud computing, and you probably have seen this in different places. So first we have the software as a service. So the Software as Service is a third-party hosting an application, and makes it available on the Internet. You can have Salesforce, Google Apps, Facebook, you have a mail services, like Hot-mail, like Gmail, is pretty much the most common use of a Cloud computing service, which is a Software as a Service. There's a lot of Software as a Service applications out there, anywhere from web applications that you can find on the Internet to do charts, or to do graphic on pictures, and file editing, and a lot of information about Software as a Service. So what I want to do take away with us is that, software as a service is based on the Cloud, and it was the fact that you can use an application, and actual application that you could get benefit from online. You don't need it in your computer, you don't need to install anything, it is host out there and you can use it. Then we have the Platform as a Service, and as you may interfere here, you're actually getting your own platform. You're not getting any more in application, but there's a whole platform that allows you to develop, or run, or manage applications without the complexity of maintaining your own infrastructure. You don't need to have your infrastructure there. So you will purchase from a vendor, the environment where you will run your tasks. This could be from middleware, from a database environment, a Java, Sandbox where you can develop applications, where you can have developers working in there, you don't really need to have the whole platform to do that, but you will purchase that from a vendor that will give you that service, that's the whole spirit of the Platform as a Service. Then last but not least, you will have Infrastructure as a Service, which delivers a whole computer infrastructure, anywhere from storage servers, network divides, etc. You can have a whole data center as a service, and this will be your infrastructure. If you don't want to purchase network devices, if you don't want to have routers or switches, if you don't have space for them, you could actually get those in an Infrastructure as a Service model, where you can purchase the right to use, or the networking device, and you could use the remotely and it will serve all of your needs, but you don't have the actual device in there.
