CLOUD COMPUTING SEM 3

Hello students, So far we covered the entire classification (taxonomy) of Virtualization. In the business world, Xen, VMWare and HyperV are some of the leading virtualization products. Xen uses ParaVirtualization technique , VMWare uses Full Virtualization technique whereas HyperV uses the both Para and Full Virtualization techniques together Xen and HyperV are Type 1 Hypervisors which run directly over the hardware, whereas VMWare is a Type 2 Hypervisor, which runs above the operating system We dig deeper into Microsoft HyperV in this lecture Some of you may have partitioned your hard disk to install two operating systems on your hard disk. HyperV uses same technique to manage different virtual machine HyperV automatically creates, uses and manages partitioning to enable different guests. It has one master partition managing all other partitions called child partitions We dig further into the enlightened I/O technology utilized by Hyper-V that improves performance by allowing direct...

Hello students, So far we covered the entire classification (taxonomy) of Virtualization. In the business world, Xen, VMWare and HyperV are some of the leading virtualization products. Xen uses ParaVirtualization technique, VMWare uses Full Virtualization technique whereas HyperV uses the both Para and Full Virtualization techniques together We dig deeper into Xen and VMWare in this lecture Xen Xen uses the ring-based ISA security model to prevent any sensitive priviledged instructions been executed by normal users running their their virtual machines. Xen also introduces the feature of web http access to configure and manage the virtual machines over the web. Xen is popularly used by AWS cloud provider. VMWare VMWare was the first company to introduce virtualization. When it arrived, it provided a heavy full virtualization where entire operating system had to be loaded in every virtual machine. VMware also uses ring-based ISA security model. VMware provides three key flavours of vir...

Hello students, In our last lecture we introduce system level virtualization and hypervisor was one of the key software that emulates a machine. Hypervisor is like a middle-person which co-ordinates the process of creating and managing virtual machines on one side and on the other side it manages all system hardware operations, either with the help of operating system or without it, depending which type of Hypervisors it is. When it comes to dealing with system operations, we are essentially dealing with actual physical hardware (actual hard disk, actual memory, actual processor, actual network etc.) via instruction set architecture (ISA) In this lecture, we focus on four techniques that can be utilized by Hypervisors to virtualize the underlying hardware/system Hardware assisted Virtualization (= VMM + custom hardware) Full Virtualization (= full virtual machine inclusive of OS and apps over it) Para Virtualization  (= modified guest OS + thin VM) Partial Virtualization (= Virtu...

Hello students, In todays lecture we dive inside system level emulation . We look at two key system mechanics, the machine and the hypervisor. When we think of system, it refers to the machine hardware (processor, memory, peripheral devices) which understand only machine instructions . Our operating system executes with the help of these hardware specific machine instructions. Machine Reference Model, ISA We begin the lecture by understanding the machine reference model to understand what makes any system work. ISA or Instruction Set Architecture (consisting of machine instructions) is at the core that ultimately manages, controls, instructs this hardware. All our system programs (including operating system) uses ISA to manage, control, instruct the hardware Some ISA instructions can delete, destroy, obstruct your system and hence such sensitive privileged ISA instruction has to be securely managed using ring-based ISA Security model. Hypervisor (Virtual Machine Manager) We finally ...

Hello students, In our last lecture we saw that for any type of virtualization, there are three basic components namely the host, virtualization layer and the guest. In this lecture we have bird's view of taxonomy of Virtualization (classification into categories and types of Virtualization) . Virtualization is emulating some real thing. In our last lecture, we saw how an electric extension board emulates a live electric point. In computers, that real thing which we want to emulate can be a hard disk, or a machine or a operating system etc. Emulating a hard disk, would mean, emulate as if I have my own file system, folders. I should be able to save files in my folder. My emulation copy is private to me and no one else can access it. When we share our desktop to somebody through a software like AnyDesk, it is an emulation of what's happening on the real desktop, onto somebody's remote screen. This is one type of emulation/virtualization example. In specific, this is called...

Hello students, We start with a new topic namely Virtualization in this lecture. You would have come across an electric socket plug point in your house where you put in a plug to connect to one device. That device can be your TV or your mobile charger or your computer. But how does one use the same electric socket to connect to all devices at the same time. I can use an electric extension board which has multiple electric sockets in it as output and the other end is connected to the real single electric socket input point. In this case, your main electric point becomes the "host", the extension board becomes the "virtualization layer" and your TV, mobile and computer become the "guest" Such type of problems are called virtualization type of problems, where you have one physical device that needs to be shared with multiple users at the same time. Though there is one physical device, I may create three or more virtual devices (guest) out of single physical...