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A software appliance is a software application that might be combined with just enough operating system (JeOS) for it to run optimally on industry standard hardware (typically a server) or in a virtual machine. In essence the term ''software appliance'' is designating the software distribution or the firmware that is running a computer appliance.〔''(SAN Data Center )''- Network World〕〔''(Routers )''- About.com〕 Virtual appliances are a subset of software appliances. The main distinction is the packaging format and the specificity of the target platform. A virtual appliance is a virtual machine image designed to run on a specific virtualization platform, while a software appliance is often packaged in more generally applicable image format (e.g., Live CD) that supports installations to physical machines and multiple types of virtual machines.〔(【引用サイトリンク】 VirtualBox changelog )〕〔Wu C F, Wang Y S, Liu G N, Amies, A, 2012, (Create solutions on IBM SmartCloud Enterprise: Transfer image assets between different accounts ) ''IBM developerWorks'', June 6.〕 Installing a software appliance to a virtual machine and packaging that into an image, creates a virtual appliance. ==Benefits== Software appliances have several benefits over traditional software applications that are installed on top of an operating system: * Simplified deployment: A software appliance encapsulates an application's dependencies in a pre-integrated, self-contained unit. This can dramatically simplify software deployment by freeing users from having to worry about resolving potentially complex OS compatibility issues, library dependencies or undesirable interactions with other applications. This is known as a "toaster." * Improved isolation: software appliances are typically used to run applications in isolation from one another. If the security of an appliance is compromised, or if the appliance crashes, other isolated appliances will not be affected. * Improved performance: A software appliance does not embed any unused operating system services, applications or any form of bloatware hence it does not have to share the hardware resources (CPU, memory, storage space, ...) usually consumed by these on a generic OS setup. This naturally leads to faster boot time and application execution speed. In the case where multiple software appliances share and run simultaneously on the same hardware (on a virtualization platform for example) this will not hold true as running n instances of a software appliance (OS + software application) will consume more hardware resources than running n instances of a software application on 1 instance of an operating system due to the overhead of running n - 1 more instances of operating system.抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「software appliance」の詳細全文を読む スポンサード リンク
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