Glossary

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Application Streaming: Streaming is a transport technique where applications or elements of an application are transferred to a remote client, then read, interpreted, and run in real time. Media streaming is commonly used to show videos or play audio, and application streaming generally allows applications to start remotely (with minimal code present), while other code is transferred to the client in the background (and is then ready to use when needed).
Application Virtualization: Application virtualization is the separation of the application from OS and applies to applications on all tiers from servers down to desktops (where applications or application components run). This is generally accomplished through encapsulation. Encapsulation and isolation from the underlying OS changes the paradigm of how applications install and interact with the OS. This allows applications to be easily moved from system to system, patched or updated without interference to other applications or the OS and co-exist with other applications without conflict. Additionally applications can be copied, backed-up, or archived just as a single file can and be controlled and monitored. Application virtualization is the technology that truly separates the infrastructure (servers and OS) lifecycle from the application lifecycle.
appzero Admin: Tool for administering VAAs
appzero Creator: Wizard-based tool for creating VAAs – capturing an application with all of its dependencies.
appzero Director: appzero's run-time component
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Capsules: A capsule embodies an isolated application and all of its dependencies, such that an application embodies in a capsule can run on any host OS in the family, regardless of the specific OS personality. With encapsulation the application's dependency on the OS has been neutralized.
Cloud Computing: (Source: Wikipedia) Cloud computing refers to the use of Internet ("cloud") based computer technology for a variety of services. It is a style of computing in which dynamically scalable and often virtualised resources are provided as a service over the Internet. Users need not have knowledge of, expertise in, or control over the technology infrastructure "in the cloud" that supports them. The cloud is a metaphor for the Internet, based on how it is depicted in computer network diagrams, and is an abstraction for the complex infrastructure it conceals.
Cloud Lock-In: Cloud lock-in refers to the degree of difficulty associated with moving an application from one cloud provider to anywhere else – whether to another provider or back to your own data center. Cost, time, level of effort, and portability of data are the major sources of cloud lock-in. appzero busts cloud lock-in with applications and data that are 100% portable.
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Encapsulation: Encapsulation is the process of defining an application and all of its dependencies, then locating them under one physical and isolated folder or entity.
Enterprise App Store: appzero has pre-packaged some popular applications as VAAs and made them available at no cost in the Enterprise App Store. The Enterprise App Store is a place where interested parties can test-drive VAA instant-on provisioning of live server applications in the comfort of their own environments. Further on in the adoption cycle, appzero envisions the Enterprise App Store as a marketplace in which ISVs can showcase their own products in VAA form.
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Grid Computing: Grid computing is a distributed computing technique where disparate computing (and storage) resources are organized to perform a computing task. The computing resources can be remotely federated through the Internet or other more secure networks. Much like a utility company's power grid, a computing grid can be used simultaneously by various users with varying computing requirements. Grid computing is often used to tackle computations of enormous scale that could not easily be completed by super computers.
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Hardware Virtualization: This describes technology that emulates hardware to enable multiple operating systems to co-exist on the same platform. Typically a hypervisor is used to deliver the hardware emulation. With hardware virtualization a complete OS is run in each virtual session including kernel, directory structures and user mode OS services.
Hypervisor: A hypervisor exists as a control layer between the hardware operating system(s). A hypervisor allows multiple operating systems to run on the same physical hardware. There are two common types of hypervisor architectures; bare-metal or hosted. Bare-metal architecture enables the hypervisor to run directly on the hardware (with no other OS needed). In a hosted architecture (type 2) the hypervisor resides on top of an existing installed OS, which in turn hosts guest OSs above it (total of three layers).
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jeOS: Just-enough-operating-system is the term many suppliers of VA’s use. appzero VAAs contain zero operating system (zeOS)
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Network Virtualization: Network virtualization is the use of logical network entities that utilize the underlying physical components of the network. The original network virtualization technology is the Virtual LAN (VLAN). This networking technology maps two disparate networks into a single, unified logical network entity. The VLAN is used in such a way that makes it appear as though everything was physically located together, though in reality, there may be remote connections defined. This same technology can be used to segment one contiguous network system. Applications or services in the server are given unique network identities, and routing within the server is handled along with networking protocols. The use of networking protocols effectively isolates the applications and services, often making them easier to monitor and manage.
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OS Virtualization: OS virtualization is the creation of separate and partitioned run-time environments all within the same overall OS. The way that applications are installed and interact with the OS is not changed, so there are no changes of substance to the application lifecycle. These separate runtime environments rely on a single kernel instance and managed by the host OS each partition in the system shares that kernel. Much of the OS user space, though not the kernel, is replicated in each partitioned runtime environment. Solaris Containers and Zones are one of the better known OS virtualization environments.
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Para-Virtualization: Para-virtualization is a virtualized server technique that emulates real or fictional hardware for a modified guest OS. The para-virtualized server is a modified guest OS running on top of the hypervisor (virtual machine monitor). The guest OS has been modified so that the guest OS makes system calls directly to the hypervisor (not executing I/O instructions directly to the machine), and the hypervisor simulates the machine feedback (and negotiates with the actual machine). The main difference between a virtual machine and para-virtualization is that the guest OS on a virtual machine is an unmodified off-the-shelf product, but the guest OS in para-virtualization is modified to work more directly with the hypervisor.
Physical to Physical Migration: Physical to physical migration (P2P) defines the process of moving a complete OS environment, and the installed applications, from one physical server to another physical server. This is done by cloning drives and putting the cloned drive into a new server, using server virtualization as an intermediate process, or by using application virtualization to easily control the movement of applications from one physical environment to another.
Physical to Virtual Migration: Physical to virtual migration (P2V) defines the process of capturing and migrating a complete OS environment, and the applications installed on it from a physical server to a virtual environment.
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Server Virtualization: Server virtualization is a generalized term describing the ability to host multiple complete OS images (including or excluding a kernel) on a single hardware platform. Both OS virtualization and hardware virtualization technologies result in the creation of a virtual server. The way that the OS interacts with the hardware platform is modified so that multiple OS instances can share the underlying hardware platform. Server virtualization is often used to consolidate multiple smaller (or older) servers onto a single, large server, without changing how the applications or OS is managed.
Storage Virtualization: Storage virtualization is the abstraction of the physical storage from the logical storage. While the actual physical storage may include several separate storage devices of different capacity and performance, storage virtualization presents a single logical storage entity. This means that the Storage Area Network (SAN) may consist of storage pools and storage devices in different locations at the physical level, but the user would see a single (often very large) storage entity, which can, from the user perspective, be managed centrally as well.
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Utility Computing: Utility computing is a metered service where computing or storage resources are provided on a needed basis similar to the way public utilities (water, electricity, telephone, etc.) are provided to homes and paid for as they are used. The purest form of utility computing requires two service characteristics metered billing and dynamic resource allocation. Customers of utility computing are not billed for a specific computer or server but are billed just for the computing or storage facilities and cycles used. In the simplest terms, utility computing implies the capability to use more resources temporarily and on-demand during peak periods.
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VAA Instance: A Single running copy of an Operating System on a physical or virtual server machine on which any number of VAAs may be accessed.
Virtual Appliance: (Source: Wikipedia) A virtual appliance is a minimalist virtual machine image designed to run under some sort of virtualization technology (like VMware Workstation, Citrix XenServer, VirtualBox or many others). Virtual appliances are a subset of the broader class of software appliances. Like software appliances, virtual appliances are aimed to eliminate the installation, configuration and maintenance costs associated with running complex stacks of software. A key concept that differentiates a virtual appliance from a virtual machine is that a virtual appliance is a fully pre-installed and pre-configured application and operating system environment whereas a virtual machine is, by itself, without application software.
Virtual Application Appliance (VAA): AppZero has pioneered the VAA which encapsulates an application and all of its dependencies for instant provisioning of a server-based application. Unlike a VA, AppZero VAAs contain zero operating system.
Virtual Machine: A virtual machine is a virtualized server emulating real or fictional hardware for an unmodified guest OS. The virtual machine is installed as an application on the host OS. Applications are installed normally in the virtual machine environment, and are unaware that they exist on a virtual machine (as opposed to a physical machine) – all of the OS duties needed by the application are performed by the virtual machine (not the host OS).
Virtual to Physical Migration: Virtual to physical migration (V2P) describes the process of installing a virtual environment (i.e., virtual machine) onto a physical server.
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zeOS: zero operating system. appzero VAAs contain zero OS