Google Chrome OS

300px Google Chrome OS with the new Aura window manager
Company / developer	Google Inc.
Programmed in	C, C++
OS family	Unix-like
Working state	Preinstalled on specific hardware (Chromebooks)
Update method	Rolling release
Package manager	Portage
Supported platforms	x86, ARM
Kernel type	Monolithic: Ubuntu[1] Linux kernel
Default user interface	Graphical interface based on the Google Chrome browser
License	Google Chrome OS Terms of Service[2]

Google Chrome OS is a Linux-based operating system designed by Google to work exclusively with web applications. Google announced the operating system on July 7, 2009 and made it an open source project, called Chromium OS, that November.^[3][4]

Unlike Chromium OS, which can be compiled from the downloaded source code, Chrome OS only ships on specific hardware from Google's manufacturing partners.^[5] The user interface takes a minimalist approach, resembling that of the Google Chrome web browser. Since Google Chrome OS is aimed at users who spend most of their computer time on the Web, the only application on the device is a browser incorporating a media player and a file manager.^{[4][6][7][8][9]}

The launch date for retail hardware featuring Chrome OS slipped after Google first announced the operating system: from an initial forecast date in late 2010 to June 15, 2011, when "Chromebooks" from Samsung (and then Acer in July) actually shipped.^{[10][11][12][13][14]}

History[link]

Google developers began coding the operating system in 2009, inspired by the growing popularity and lower power consumption of netbooks and the focus of these small laptops on Internet access. To ascertain marketing requirements for an operating system focused on netbook Web transactions, the company did not do the usual demographic research generally associated with a large software development project. Instead, engineers relied on more informal metrics, including monitoring the usage patterns of some 200 Chrome OS machines used by Google employees. Developers also noted their own usage patterns. Matthew Papakipos, former^[15] engineering director for the Chrome OS project, put three machines in his house and found himself logging in for brief sessions: to make a single search query or send a short email.^[6]

On November 19, 2009, Google released Chrome OS's source code as the Chromium OS project.^[4] As with other open source projects, developers are modifying code from Chromium OS and building their own versions, whereas Google Chrome OS code will only be supported by Google and its partners, and will only run on hardware designed for the purpose. Unlike Chromium OS, Chrome OS will be automatically updated to the latest version.^[16] InformationWeek reviewer Serdar Yegulalp wrote that Chrome OS will be a product, developed to "a level of polish and a degree of integration with its host hardware that Chromium OS does not have by default," whereas Chromium OS is a project, "a common baseline from which the finished work is derived" as well as a pool for derivative works. The product and project will be developed in parallel and borrow from each other.^[17]

At a November 19, 2009 news conference, Sundar Pichai, the Google vice president overseeing Chrome, demonstrated an early version of the operating system. He previewed a desktop which looked very similar to the Chrome browser, and in addition to the regular browser tabs also had application tabs, which take less space and can be pinned for easier access. At the conference, the operating system booted up in seven seconds, a time Google said it would work to reduce.^{[16][18][17][19]}

Also on November 19, 2009, Chris Kenyon, vice president of OEM services at Canonical Ltd announced that Canonical "is contributing engineering to Google [Chrome OS] under contract. In our discussions, Sundar Pichai and Linus Upson made it clear that they want, wherever feasible, to build on existing components and tools from the open source community without unnecessary re-invention. This clear focus should benefit a wide variety of existing projects and we welcome it."^[20]

On January 25, 2010, Google posted notes, images and a video of a conceptual design showing how a Chrome OS user interface might look on a tablet computer with a 5–10 inch screen. The design would include the same basic layout as on netbooks, but with a touch interface; an onscreen qwerty keyboard in different layouts; large, square icons placed above the tabs; and panels placed along the bottom edge that could be opened with an upward dragging motion.^[21][22] The posting was made two days before Apple announced the iPad tablet.^[23] On March 16, 2011, several changes to Chromium OS were made which indicate the development of a tablet version of Google Chrome OS.^[24]

In March 2010, Google indicated that consideration is being given to developing two versions of the operating system, a consumer version and an enterprise version.^[25]

Cr-48 prototype hardware[link]

The Cr-48 showing the setup screen seen when first booting up a Chromebook

At a December 7, 2010 press briefing, Google announced the Cr-48 laptop, a reference hardware design to test the Chrome OS operating system. It was named after Chromium-48, an unstable isotope of the metallic element known as Chromium^[26]. The laptop's design broke convention by replacing the caps lock key with a dedicated search key.^[27]

The Cr-48 was intended for testing only, not retail sales.^[28][29][30] Google addressed complaints that the operating system offers little functionality when the host device is not connected to the Internet. The company demonstrated an offline version of Google Docs running on Chrome OS and announced a 3G plan that would give Chrome OS users 100 MB of free data each month, with additional paid plans available from Verizon.^[13]

About 60,000 Cr-48s were distributed to testers and reviewers in early December 2010. Reviews of Chrome OS running on the Cr-48 in mid-December 2010 indicated that while the project held promise, it still had some distance to go before being ready for market.^[31][32]

On March 8, 2011, Google Product Management vice president Sundar Pichai stated that the last of the 60,000 Cr-48s had been shipped.^[33]

The Cr-48 notebooks have additional unused hardware components for implementation at a future date, including a Bluetooth 2.1 controller.^[34] The USB port only acts as a keyboard, mouse, ethernet adapter, or USB storage port and will not work as a printer port as there is no print stack on the operating system.^[35] Adding further hardware outside of the previously mentioned items will likely cause problems with the operating system's "self knowing" security model.^[36] Users are encouraged to use a secure service called Google Cloud Print to print to legacy printers connected to their desktop computers, or connect an HP ePrint, Kodak Hero, Kodak ESP, or Epson Connect printer to the Google Cloud Print service for a "cloud aware" printer connection.^[37]

Commercial hardware: Chromebooks[link]

Google initially named several development partners working on hardware for the operating system, with others named in the press, including Acer, Adobe, Asus, Freescale, Hewlett-Packard, Lenovo, Qualcomm, Texas Instruments, Toshiba,^[38] Intel,^[39] Samsung,^[40][41] and Dell.^[42]

On May 11, 2011 at its Google I/O developer conference, Google announced that the first two commercially available laptops incorporating Chrome OS would be manufactured by Acer Inc. and Samsung Electronics Co., with a retail price beginning at $349. The ship date was June 15 for the United States, the United Kingdom, France, Germany, Netherlands, Italy and Spain. The Chromebooks are sold in the United States through Amazon and Best Buy; internationally through "leading retailers". Google claimed an eight-second bootup time and eight-hour operation on one battery charge, and said that the chromebooks would require no virus protection. Models equipped with 3G connectivity receive 100 megabytes of wireless data per month, free for two years, with an additional gigabyte at $20 per month. Google is also working on a Chrome OS desktop machine.^[14][43][44]

Google also announced a monthly payment scheme for business and education customers at $28 and $20 per user, per month, respectively for a three-year contract, including replacements and upgrades.^[14]

Relationship to Android[link]

Google's successive introduction of the popular Android^[45] and Google Chrome OS has put the company behind two open source, client-based operating systems. Microsoft CEO Steve Ballmer accused Google of not being able to make up its mind.^[46] Google has suggested that the two operating systems address different markets, mobile and personal computing, which remain distinct despite the growing convergence of the devices. Co-founder Sergey Brin suggested that the two systems "will likely converge over time."^[47]

Steven Levy wrote that "the dissonance between the two systems was apparent" at the 2011 Google I/O developer conference. "Each day of the event featured a keynote devoted to one system followed by a press briefing where each team leader (Android's Andy Rubin and Chrome's Sundar Pichai) unconvincingly tried to explain why the systems weren't competitive. Co-founder Sergey Brin addressed the question by saying that owning two promising OS's was a problem that most companies would love to face".^[48]

Design[link]

Early in the project, Google put online many details of Chrome OS's design goals and direction.^[49] But the company has not followed up with a technical description of the completed operating system.

User interface[link]

Design goals for Google Chrome OS's user interface included using minimal screen space by combining applications and standard Web pages into a single tab strip, rather than separating the two. Designers considered a reduced window management scheme that would operate only in full-screen mode. Secondary tasks would be handled with "panels": floating windows that dock to the bottom of the screen for tasks like chat and music players. Split screens were also under consideration for viewing two pieces of content side-by-side. Google Chrome OS would follow the Chrome browser's practice of leveraging HTML5's offline modes, background processing, and notifications. Designers proposed using search and pinned tabs as a way to quickly locate and access applications.^[50]

New window manager and graphics engine[link]

On April 10, 2012, a new build of Chrome OS offered a choice between the original full-screen window interface and overlapping, re-sizable windows, such as found on Microsoft Windows and Apple's Mac OS X. The feature was implemented through the Ash window manager, which runs atop the Aura hardware-accelerated graphics engine. The April 2012 upgrade also included the ability to display smaller, overlapping browser windows, each with its own translucent tabs, browser tabs that can be "torn" and dragged to new positions or merged with another tab strip, and a mouse-enabled shortcut list across the bottom of the screen. One icon on the task bar shows a list of installed apps and bookmarks. Writing in CNET, Stephen Shankland argued that with overlapping windows, "Google is anchoring itself into the past" as both iOS and Microsoft's Metro interface are largely or entirely full-screen. Even so, "Chrome OS already is different enough that it's best to preserve any familiarity that can be preserved".^[51][52][53]

Architecture[link]

In preliminary design documents for the Chromium OS open source project, Google described a three-tier architecture: firmware, browser and window manager, and system-level software and userland services.^[54]

• The firmware contributes to fast boot time by not probing for hardware, such as floppy disk drives, that are no longer common on computers, especially netbooks. The firmware also contributes to security by verifying each step in the boot process and incorporating system recovery.^[54]
• System-level software includes the Linux kernel that has been patched to improve boot performance. Userland software has been trimmed to essentials, with management by Upstart, which can launch services in parallel, re-spawn crashed jobs, and defer services in the interest of faster booting.^[54]
• The window manager handles user interaction with multiple client windows much like other X Window managers.^[54]

Remote application access and virtual desktop access[link]

In June 2010, Google software engineer Gary Kačmarčík wrote that Chrome OS will access remote applications through a technology unofficially called "Chromoting," which would resemble Microsoft's Remote Desktop Connection.^[55] The name has since been changed to "remoting," and is "probably closer to running an application via Remote Desktop Services or by first connecting to a host machine by using RDP or VNC."^[56] Initial roll-outs of Chrome-OS laptops (Chromebooks) indicate an interest in enabling users to access virtual desktops.^[57][58]

Hardware support[link]

Google Chrome OS is initially intended for secondary devices like netbooks, not as a user's primary PC,^[18] and will run on hardware incorporating an x86 or ARM-based processor.^[7] While Chrome OS will support hard disk drives, Google has requested that its hardware partners use solid-state drives "for performance and reliability reasons"^[16] as well as the lower capacity requirements inherent in an operating system that accesses applications and most user data on remote servers. In November 2009 Matthew Papakipos, engineering director for the Google Chrome OS claimed that the Chrome OS consumes one-sixtieth as much drive space as Windows 7.^[59]

Integrated media player, file manager[link]

Google integrates a media player into both Chrome OS and the Chrome browser, enabling users to play back MP3s, view JPEGs, and handle other multimedia files while offline.^[55]

Chrome OS also includes an integrated file manager resembling those found on other operating systems, with the ability to display folders and their associated files, as well as preview and manage file contents using a variety of Web applications, including Google Docs and Box.net.^[60]

Printing[link]

Google Cloud Print is Google's proposed solution to help any application on any device to print on any printer. While the cloud provides virtually any connected device with information access, the task of "developing and maintaining print subsystems for every combination of hardware and operating system – from desktops to netbooks to mobile devices – simply isn't feasible."^[61][62] However, the cloud service would entail installing a piece of software, called a proxy, as part of Chrome OS. The proxy would register the printer with the service, manage the print jobs, provide the printer driver functionality, and give status alerts for each job.^[63]

Link handling[link]

Chrome OS was designed with the intention of having user documents and files stored on online servers. However, both Chrome OS and the Chrome browser have unresolved decisions regarding handling specific file types offline. For example, if a JPEG is opened from a local storage device, should a specific Web application be automatically opened to view it, and if so, which one? Similarly, if a user clicks on a .doc file, which website should open: Microsoft Office Live, Gview, or a previewing utility? The project director at that time, Matthew Papakipos, noted that Windows developers have faced the same fundamental problem: "Quicktime is fighting with Windows Media Player, which is fighting with Chrome." As the number of Web applications increases, the same problem arises.^[6]

Security[link]

In March 2010, Google software security engineer Will Drewry discussed Chrome OS security. Drewry described Chrome OS as a "hardened" operating system featuring auto-updating and sandbox features that will reduce malware exposure. He said that Chrome OS netbooks will be shipped with Trusted Platform Module, and include both a "trusted bootpath" and a physical switch under the battery compartment that actuates a developer mode. That mode drops some specialized security functions but increases developer flexibility. Drewry also emphasized that the open source nature of the operating system will contribute greatly to its security by allowing constant developer feedback.^[25]

At a December 2010 press conference, Google claimed that Chrome OS would be the most secure consumer operating system due in part to a verified boot ability, in which the initial boot code, stored in read-only memory, checks for system compromises.^[13]

Shell access[link]

Chrome OS includes the Chrome Shell, or "crosh", which offers minimal functionality such as ping and ssh, but no Bash-like shell abilities. In developer mode, a full-featured Bash shell can be opened via VT-2, and is also accessible via the crosh command "shell".^[64]

Reception[link]

Early on, Chrome OS was viewed as a competitor to Microsoft, both directly to Microsoft Windows and indirectly the company's word processing and spreadsheet applications—the latter through Chrome OS's reliance on cloud computing.^[65][66] But Chrome OS engineering director Matthew Papakipos argued that the two operating systems would not fully overlap in functionality because Chrome OS hosted is intended for netbooks, which lack the computational power to run a resource-intensive program like Photoshop.^[6]

Some observers claimed that other operating systems already fill the niche that Chrome OS is aiming for, with the added advantage of supporting native applications in addition to a browser. Tony Bradley of PC World wrote in November 2009: "We can already do most, if not all, of what Chrome OS promises to deliver. Using a Windows 7 or Linux-based netbook, users can simply not install anything but a web browser and connect to the vast array of Google products and other web-based services and applications. Netbooks have been successful at capturing the low-end PC market, and they provide a web-centric computing experience today. I am not sure why we should get excited that a year from now we'll be able to do the same thing, but locked into doing it from the fourth-place web browser."^[67]

A year later, Ryan Paul of Ars Technica came to similar conclusions. He wrote that Google's Cr-48 prototype "met the basic requirements for Web surfing, gaming, and personal productivity, but falls short for more intensive tasks." He praised Google's approach to security, but wondered whether mainstream computer users would accept an operating system whose only application is a browser. "In its current form, I think that the operating system could appeal to some niche audiences, like regular consumers users who really just need browsing or office productivity workers at companies that have gone Google or only use intranet apps. It's decidedly not a full-fledged alternative to the general purpose computing environments that currently ship on netbooks." Paul wrote that most of Chrome OS's advantages "can be found in other software environments without having to sacrifice native applications."^[31]

In reviewing the Cr-48 on December 29, 2010, Kurt Bakke of Conceivably Tech said: "in my household the Chromebook has turned into a family appliance and the most frequented computer in our household. Its 15 second startup time and dedicated Google user accounts made it the go-to device for quick searches, email as well as YouTube and Facebook activities. It has not turned into a device that can rival the appeal of any of our other notebooks – we have one gaming laptop, two mainstream notebooks and two netbooks in our household with five kids. The biggest complaint I heard was its lack of performance in Flash applications."^[68]

In ongoing testing, Wolfgang Gruener, also writing in Conceivably Tech, said that cloud computing at cellular data speeds is unacceptable and that the lack of offline ability turns the Cr-48 "into a useless brick" when not connected.^[69] "It's difficult to use the Chromebook as an everyday device and give up what you are used to on a Mac/Windows PC, while you surely enjoy the dedicated cloud computing capabilities occasionally."^[70] He praised a March 2011 update that included new trackpad control features, scrolling support, power improvements and a large number of bug fixes.^[71]

See also[link]

• Android (operating system)

References[link]

External links[link]

Wikimedia Commons has media related to: Chrome OS

• Release blog
• Google Chrome official blog
• Chromium OS project page
• Official Chrome OS notebooks page
• What is Google Chrome OS? on YouTube

Historical[link]

• Official announcement
• Google Chrome OS Live Webcast; November 19, 2009