Windows RT
| Microsoft Windows 的版本 | |
 | |
 | |
| 操作系统系列 | Windows NT 系列 |
|---|---|
| 内核版本 | Windows NT 6.2 |
| 开发代号 | Windows on ARM |
| 体系结构 | ARM32 |
| 最新版本 | 9200.16384.win8_rtm |
| 发布日期 | 2012 年 10 月 26 日 |
| 终止支持 | 2016 年 1 月 12 日 |
| 接替 | |
| Windows RT 8.1 | |
Windows RT（开发代号为“Windows on ARM”，一般简称为 WoA）是由 Microsoft 开发的针对 ARMv7 体系结构开发的 Windows 8 定制版本，适用于续航时间更长且专为在旅途中使用而设计的轻薄型电脑。它是桌面 ARM 体系结构操作系统的首个主要版本。与 Windows 8 一样，它于 2012 年 8 月 1 日签署 RTM，并于 2012 年 10 月 26 日正式发布。
与 Windows 8 一样，Windows RT 也是最短命的版本之一，支持于 2016 年 1 月 12 日与 Windows 8 一起结束；Windows 8.1 和 Windows RT 8.1 发布两年后。
Windows RT is a cut-down version of the Windows 8 operating system developed by Microsoft, released to the general public on 26 October 2012 alongside its more fully-featured desktop counterpart. It shipped as part of the first batch of ARM-based Windows devices, based on the Nvidia Tegra 3 and Qualcomm Snapdragon S4 (Plus and Play) system-on-chip processors.[a] Intended as a direct response to Apple's immediate success of the iPad, Windows RT sought to bring a complete overhaul to the familiar Windows user interface by introducing a full-screen tablet-oriented experience with increased emphasis on responsive touch input; most particularly, the addition of a Start screen and the introduction of the Windows Store, a digital distribution platform for applications. Windows RT additionally includes a free licensed copy of Office 2013, albeit rebranded simply as Office RT.
It is the first (and second to last) of a series of short-lived Windows desktop releases to target the 32-bit ARMv7 microarchitecture, a reduced-instruction set computing platform designed for low-power devices such as tablets and phones. The effort was spearheaded over a three-year development period under the codename Windows on ARM, and resulted in two ARM-based versions of Windows 8 for both desktop computers and a mobile counterpart, Windows Phone 8. Two separate versions of Windows Embedded 8 for ARMv7 platforms codenamed Dione and Tethys (for the Standard and Industry Pro SKUs, respectively) were also planned, but were cancelled internally for unknown reasons. Support for Windows RT ended on 12 January 2016, in line with its desktop counterpart.
Windows RT includes a number of internal restrictions bound to a hardware and software level and lacks many features found in higher-end editions of Windows 8, most especially the ability to run third-party Win32 applications under the implication of competing against the iPad. While the operating system was more positively received for its touch-based emphasis (unlike Windows 8, which had the opposite effect and eroded user trust), the artificial restrictions that were included as part of Windows RT and devices running it were subject to criticism, as they severely limited the overall usability of the operating system.
历史
Windows RT 在 2011 年 1 月的 Consumer Electronics Show 上进行了展示，在 2012 年 10 月 26 日随 Windows 8 同步上市，在上市的同时还发布了三款基于 Windows RT 的设备（例如 Microsoft Surface RT）。与 Windows 8 的其他版本相比，它包括经过定制的 Office 2013 套件，且只能启动源自 Windows 应用商店或由 Microsoft 进行数字签名的应用。在功能上，它与 Windows 8 Core 使用相同的功能集。
Development
Plans for a native ARM-based port of the Windows operating system date back to as early as April 2003, approximately two months after the release of Windows Server 2003. Initial efforts were skunkworks projects developed under commission by the United States Armed Forces for use in military deployments. The first ARM ports of Windows were first developed on top of the Intel XScale microarchitecture, a subset of the StrongARM instruction set designed for low-power devices such as PDAs. These ports were done against the Longhorn codebase (under the internal codename LongARM); the port persisted after the development reset.
Efforts were restarted in July 2009 as work on Windows 7 was being finalized,[1] as the hardware target then moved to mobile devices running on top of the ARMv6 instruction set; a cut-down version of the Windows operating system had successfully booted by January 2010.[2]
Apple's growing dominance in the mobile market, attributed to the company's far-reaching success of the iPhone and the introduction of the iPad, forced Microsoft to consider developing a competing operating system that ran under x86- and ARM-based platforms. By this time, executives took notice of the ARMv6 port, and later greenlit the project as an official port bearing the internal codename Windows on ARM. The port restarted development a third time to move to the ARMv7 microarchitecture in March 2010.[3][4]
Development of Windows RT kicked off in April 2010, a month after the Windows 8 vision document was completed.[5] The first external WoA partner drop was distributed in August 2010 starting with Windows 8 build 7792; later builds added support for hardware abstraction layer (HAL) extensions that allowed vendors to define SoC-specific hardware timers, interrupt controllers and direct memory access (DMA) controllers. The port was unveiled at the CES 2011 trade show in January 2011 to demonstrate the capabilities of the then-evolving ARM architecture, with planned support for ARM-based system-on-chip devices produced by Nvidia, Qualcomm and Texas Instruments, while Intel led efforts on x86-based Intel Atom SoCs dubbed "Low-Power Intel Architectures" (LPIAs).[6][7]
Between 2010 through 2012, ARM partners received Windows RT builds from various development branches related to SoC development efforts, and were provided specialized development kits to further facilitate porting efforts. The ARMv7 port initially targeted the Nvidia Tegra 2, Qualcomm Snapdragon QSD8250 and Texas Instruments OMAP3430 processors, but were later moved to the Tegra 3, Snapdragon MSM8660 (S3), Snapdragon S4 and OMAP4430/4470, respectively. During this time, Microsoft was developing their own flagship tablet family; the codenames GeorgeTown and GeorgeTown X respectively corresponded to ARM- and x86-based computers featuring touchscreen capabilities. This culminated into the Microsoft Surface device family, unveiled by Microsoft in 2012 with the Surface RT (an ARM-based tablet featuring a Tegra 3 SoC) and Surface Pro (a higher-end computer featuring an x86-based third-generation Intel Core processor) becoming the respective flagship devices for Windows RT and Windows 8.[8]
As development of Windows RT progressed, higher-ups in Microsoft demanded the removal of features that were originally part of the Windows operating system and the imposition of various internal restrictions which strongly hampered the overall usability of the port under the implication of competing against the iPad, despite key leaders strongly objecting to their requests.[9] Required libraries for Win32 application development were also stripped out of the public Windows SDK to facilitate development and publishing of Windows Runtime-based applications to the Windows Store.
Vendors for Windows RT devices initially included Acer,[10][11] Asus, Hewlett-Packard,[12] Dell,[13] Lenovo, Microsoft, Samsung Electronics and Toshiba.[14] Texas Instruments exited the mobile device industry in September 2012 (shortly after Windows 8 was finished) when the company deemed the mobile device market otherwise unprofitable,[15] forcing Toshiba to cancel its own flagship Windows RT tablets as consequence, citing "delayed components" that would prevent the devices from launching in time.[16] Texas Instruments' self-removal from the mobile device market was unprecedented, as specialized RTM partner drops had already been produced for the company.
Windows 8 released to general availability on 26 October 2012 alongside the ARM-based Surface RT and Asus VivoTab RT tablets, to overwhelmingly negative criticism. Windows RT, despite receiving praise for its touch-friendly user experience (in stark contrast to the scathing criticism Windows 8 received for the same user experience), was strongly criticized for its lackluster library of applications and the number of artificial internal restrictions imposed against all Windows on ARM devices, and was considered a commercial failure in the months that followed.
Main changes
Windows RT contains many of the same changes included as part of Windows 8 as both operating systems shared the same codebase, although the feature set in Windows RT has been drastically reduced compared to its more advanced desktop counterpart. Unlike its desktop-based counterpart, a free copy of Office 2013 is included as part of the operating system free of charge to all Windows RT device owners. All Windows RT devices shipped with a digital OA3x product key embedded into hardware, and could be re-activated at any given time with no maximum install limitations. In addition to this, a free licensed copy of the Office 2013 Home and Student edition is included as part of Windows RT under the moniker Office RT.[b]
A number of internal restrictions bound to a hardware and software level exist in Windows RT. Specifically, the operating system can only run on ARMv7-based processors featuring UEFI Class 3 firmware. For added security, Secure Boot is required in order to ship Windows RT devices, and Code Integrity lockdown policies alongside product policy restrictions have been instituted to reduce the risk of malware spread. Many features found in higher-end editions of Windows 8 are absent in RT, which included (but were not limited to) enterprise features such as Active Directory Domain Services domain join support, the removal of communications applications such as the Remote Desktop protocol, and media features such as Windows Media Player and Windows Media Center. The ability to run third-party Win32 applications was also disabled entirely as applications delivered via the Windows Store were strongly favored under the implication of competing against the iPad, despite key leaders strongly objecting to their requests.[c] As such, only applications downloaded from the Store (and applications bundled as part of the Windows operating system) can run on Windows RT.
Device Encryption is a new BitLocker Drive Encryption (BDE) feature exclusive to Windows RT, which allows BDE to automatically encrypt the complete contents of any ARM-based device immediately after installation so long as a Trusted Platform Module with Connected Standby support is present; it does not have a dedicated user interface which would be added as part of Windows 8.1's release. Device encryption may be temporarily disabled in the Windows Preinstallation Environment using the manage-bde utility.
The public Windows 8 SDK was released in such a way that core components needed to compile Win32 applications against the ARM architecture, specifically GDI and USER, were removed to encourage developers working on ARM applications to shift to developing C#- and JavaScript-based programs running under the Windows Runtime, to be published onto the Windows Store.[d]
Criticism and controversy
Windows RT was received more positively by various technology outlets than Windows 8 for its touch-oriented controls and user interface, but was also subject to criticism over its internal restrictions that prevented the usage of applications that either did not originate from either the Windows Store or were not digitally signed by Microsoft, coupled with the extremely limited library of available applications targeting the ARMv7 architecture, resulting in expectations falling short entirely.[17] As Microsoft had intended to make Windows 8 and RT a direct competitor to Apple's own iOS-based device platforms, a number of features that were included in x86-based desktop releases of Windows such as communications facilities, media capabilities and enterprise features were completely stripped out of the ARM port under the orders of upper management in spite of objections from key leaders, without adequate explanation for their removals.[9]
Windows 8.1 and its ARM-based counterpart, Windows RT 8.1, were released on 17 October 2013 in an attempt to address their predecessors' shortcomings, but was still not successful as it failed to address more serious issues. The market failure of Windows RT led to the cancellation of the Surface Mini in 2014, and ultimately the operating system's discontinuation in 2015.
主要新增功能与更改
尚待完善和确认。
删除或降级功能
在 Windows RT 中，有自己的删除或降级的功能。相比 Windows 8 来说，在 Windows RT 中不包含以下功能：
- Windows Media Player
- Windows Media Center
- 家庭组创建（你可以加入现有家庭组但无法创建新的家庭组）
- 远程桌面
- 域加入
- IIS
研究结果
Windows RT 可以非正式安装 Windows Media Player。具体来说：
- 解压 Repair Content 中 BaseOS 相关包
- 解压需要的语言包
- 挂载任意 SKU 的对应系统版本映像
- 使用 DISM 按照给出的顺序安装包
- 保存并卸载映像
示例 (在 Build 8400 上安装中文 Windows Media Player 所需的包) microsoft-windows-mediaplayback-oc-package~31bf3856ad364e35~arm~~6.2.8400.0.mum microsoft-windows-mediaplayer-package~31bf3856ad364e35~arm~~6.2.8400.0.mum microsoft-windows-mediaplayer-package-ua~31bf3856ad364e35~arm~~6.2.8400.0.mum Microsoft-Windows-MediaPlayer-Package-ua~31bf3856ad364e35~arm~zh-CN~6.2.8400.0.mum
已知版本列表
Milestone 1 及更早
Milestone 1
Milestone 2
Milestone 3（Developer Preview）
Developer Preview Escrow
Public release
Beta（Consumer Preview）
Beta Escrow
Public release
Release Candidate (Release Preview)
Release Candidate Escrow
Public release
Pre-RTM
RTM Escrow
RTM
Post-RTM
注
- ↑ Texas Instruments devices based on the OMAP4430/4470 SoC designs were cancelled a month prior to launch.
- ↑ The version of Office 2013 that shipped as part of Windows RT was an incomplete preview release - an upgrade to the final version of Office 2013 was distributed to all users free of charge.
- ↑ Third-party applications can only run if Secure Boot and User-Mode Code Integrity were disabled in both firmware and software, respectively. Exploits to disable the arbitrary code restrictions present in Windows RT exist and have been utilized against existing hardware, and the Windows 10 SDK toolchains can be used to build and run applications targeting Windows RT.
- ↑ This change was reverted in Windows 10 to facilitate development of applications on supported ARMv7 editions such as IoT Core and Windows 10 Mobile.
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- ↑ Windows 8 build 7915's Driver Kit;
ntsoc.h - ↑ Sinofsky, Steven. Building Windows for the ARM processor architecture, Microsoft Developer Blog - Building Windows 8. 9 February 2012. Archived from the original on 17 January 2016.
- ↑ Sinofsky, Steven. 100. A Daring And Bold Vision, Hardcore Software: Inside the Rise and Fall of the PC Revolution. 2 October 2022.
- ↑ Larson-Green, Julie et al. The Windows 8 Vision. 24 March 2010.
- ↑ Edition-specific Windows Setup unattended answer files in Windows 8 build 7746
- ↑ Clarke, Gavin. Microsoft embraces ARM with Windows 8, The Register. 5 January 2011.
- ↑ Sandoval, Greg. Windows 8 to support x86, ARM 'system on a chip', CNET. 5 January 2011.
- ↑ Rushe, Dominic. Microsoft reveals Surface Windows 8 tablets, The Guardian. 18 June 2012.
- ↑ 9.0 9.1 Giles, Aaron. Response to inquiry on Windows RT branding. 17 August 2023.
- ↑ Huet, Natalie; Peters, Hans-Juergen. Acer delays Windows RT tablets after Microsoft moves into market, Reuters. 30 October 2012.
- ↑ Shah, Agam. Acer waits for Windows RT 8.1 to make tablet decision, PCWorld. 3 May 2013.
- ↑ Poeter, Damon. HP scraps Windows RT tablet plans, PCMag UK. 29 June 2012.
- ↑ Dell Debuts Stunning Additions to XPS Brand: Superb Performance and Design without Compromise, Dell Newsroom. 30 August 2012. Archived from the original on 18 March 2013.
- ↑ Klug, Brian. TI Demos Windows RT UI Performance on OMAP 4470, AnandTech. 14 June 2012.
- ↑ Carew, Sinead. Texas Instruments eyes shift away from wireless, Reuters. 25 September 2012.
- ↑ Portnoy, Sean. Toshiba bows out of Windows RT tablet race, ZDNET. 14 August 2012.
- ↑ Chang, Alexandra. Windows 8 review: A big, beautiful shaky step forward, CNN. 25 October 2012: "Even more confusing than a bunch of tiles: There are several versions of Windows 8. Most importantly, Windows RT, which comes built-in on the Surface RT tablet and other devices, is far less capable than Windows 8 and Windows 8 Pro. [...] In short, Microsoft will need to clearly explain that Windows RT is a mobile OS that shares the same skin as Windows 8, but is not a fully capable PC. It cannot run the same desktop programs as full Windows 8, only apps downloaded from the Windows Store."