Lesson 3, Distributed Computing for Performance and Reliability. So we can see here that a user is connecting to a Cloud desktop by way of a of a remote desktop connection. Which is typically what most users will do, often users cannot detect when computing services are Cloud services or whether they are native or local services. Cloud services such as disk networking and memory are completely transparent to the user. Desktop services will need to be reached by way of some kind of remote connection either through our remote desktop connection. Like we can see here or in the Linux world through some kind of secure connection client such as PuTTY or some other secure connection client. And we can see here Cloud desktops can be run from a user's native desktop. And this greatly increases the computing resources for the users. So we can see here this is an example of a native desktop that a user will be running. And then by way of remote desktop connection, this user has brought up a Cloud desktop. So and the user can access them back and forth just like, well just like running any other software just simply needs to activate this window in which the Cloud desktop is running. And all the applications, all the additional memory, any kind of custom software or commercial software that's available in the Cloud desktop can be used by the user. And users can even copy paste between these desktops. Almost all Cloud services are delivered by a method called virtualization. In this context virtualization means the form of how an end user will consume the Cloud services. From the user perspective, virtualized hardware is identical to physical hardware. So the way the information is processed should appear be no different. Virtualized hardware is part of the Cloud providers physical data center. And it is allocated to customers for periods of time throughout the day. And virtual processing shares the Cloud providers hardware, disk and storage, memory, networking, and desktop. And again, these are all virtualized and then allocated to customers as needed. The software that actually performs the virtualization is a software product called a hypervisor. And what that does it actually allocates a computer's hardware and is able then to allocate it to several instances which can be consumed by one or more customers. So as we can see here, we have one computer and the hypervisor is running and then, it essentially becomes virtual hardware to the end user. We can see an operating system then installed on this virtual hardware and we can see applications running. Each one of these will have its own network address, therefore can be connected to by the customers. There are two types of hypervisors. Type one runs directly on the hardware and the hypervisor also provides the operating system. So we can see a type 1 here and this this may be more efficient but it's a more complex type of solution. But we can see here the Bear hardware then the hypervisor is installed running on their bear hardware with a specialized operating system for this hardware. And then we can see all applications and operating systems then all allocated virtually to the end-user. A type 2 hypervisor is installed on top of usually a typical operating systems such as Linux or Windows. And as we can see here the model then from the hypervisor is the same, the applications and the virtualized operating system. This well is a virtualized hardware is delivered to the end user. Managed infrastructure allows a firm to administer hardware and other services exactly the same as they manage any kind of software. And we discussed this earlier. Software can be installed as needed and has a software is as additional software is installed, very little overhead is consumed. Software licenses can be administered as needed. Physical local hardware almost always has large overhead and a lot of fixed cost associated with it, because the firm must grow into it. The cost is high enough that a firm must install hardware that exceeds the firm's current needs. So the can actually grow into the hardware. Therefore we can start to see many of the advantages of Cloud because there is no hardware that needs to be grown into it. Cloud provides rich consoles that allow local administrators to manage the firm's Cloud infrastructure. And we can see here one example of a console, and the firm can actually manage it for themselves. The console allows the operators and administrators to access the Cloud service offerings and add or remove services that are part of the firm's current Cloud infrastructure. So we can see here there are actions administrators can monitor what infrastructure is running and add as needed. Service offerings from Azure. So we can see here that Azure which is a popular Cloud provider for Microsoft offers artificial intelligence, analytics, blockchain. Virtual servers, which is very popular which we have seen. Database services, developer tools and developer tools can get to be very expensive. However, though they can be accessed through the Cloud on a subscription type of basis. DevOps type of products, identity management, Internet-of-things, networking and many more services.
