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Xerox Star
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The Star workstation, officially known as the Xerox 8010 Information System, was introduced by Xerox Corporation in 1981. It was the first commercial system to incorporate various technologies that today have become commonplace in personal computers, including a bitmapped display, a window-based graphical user interface, icons, folders, mouse, Ethernet networking, file servers, print servers and e-mail.
The name "Star" technically refers only to the software sold with the system for the office automation market.
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Encyclopedia
The Star workstation, officially known as the Xerox 8010 Information System, was introduced by Xerox Corporation in 1981. It was the first commercial system to incorporate various technologies that today have become commonplace in personal computers, including a bitmapped display, a window-based graphical user interface, icons, folders, mouse, Ethernet networking, file servers, print servers and e-mail.
The name "Star" technically refers only to the software sold with the system for the office automation market. The 8010 workstations were also sold with LISP- and Smalltalk-based software, for the smaller research and software development market.
History
The Xerox Alto
The Xerox Star systems concept owes much to the Xerox Alto, an experimental workstation designed by the Xerox Palo Alto Research Center (PARC) in the 1970s. Although by 1979 nearly 1000 Ethernet-linked Altos were in use at Xerox and another 500 at collaborating universities and government offices, it was never intended to be a commercial product . While Xerox had started in 1977 a development project which worked to incorporate those innovations into a commercial product, their concept was an integrated document preparation system, centered around the (then expensive) laser printing technology and oriented towards large corporations and their trading partners. When that system was announced in 1981 , the cost was about $ 75,000 for a basic system, and $16,000 for each additional workstation.
The Xerox Star development process
The Star was developed at Xerox's Systems Development Department (SDD) in El Segundo, California, which had been established in 1977 under the direction of Don Massaro. A section of SDD ("SDD North") was located in Palo Alto, California, and included some people borrowed from PARC. SDD's mission was to design the "Office of the Future", a new system that would incorporate the best features of the Alto, was easy to use and could automate many office tasks.
The development team was headed by David Liddle, and would eventually grow to more than 200 developers. A good part of the first year was taken up by meetings and planning, the result of which was an extensive and detailed functional specification (known internally as the "Red Book"). This became the bible for all development tasks. It defined the interface and enforced consistency in all modules and tasks. All changes to the functional specification had to be approved by a review team which rigorously maintained standards.
One group in Palo Alto worked on the underlying operating system interface to the hardware and programming tools. Teams in El Segundo and Palo Alto collaborated on development of the user interface and user applications.
The staff relied heavily on the very technologies that they were working on—file sharing, print servers and e-mail. They were even connected to the Internet, known as the Arpanet at that time, which allowed them to communicate between El Segundo and Palo Alto.
The Star was implemented in the Mesa programming language, a direct precursor to Modula-2 and Modula-3. Mesa was not object-oriented, but tools and programming techniques were developed which allowed pseudo object-oriented design and programming. Mesa required programmers to create two files for every module, a definition module which specified data structures and procedures for each object and one or more implementation module that has the actual code for the procedures.
The Star team used a sophisticated integrated development environment known internally as Tajo and externally as Xerox Development Environment or XDE. Tajo had many similarities with the Smalltalk-80 environment, but it had many additional tools. For example, the DF version control system, which required programmers to check out modules before they could be changed. Any change in a module which would force dependent modules to change were closely tracked and documented. Changes to lower level modules required various levels of approval.
The software development process was intense. It involved a lot of prototyping and user testing. The software engineers had to develop new network protocols and data-encoding schemes when those used in PARC's research environment proved inadequate.
Initially, all development was done on Alto workstations. These were not well suited to the extreme burdens placed by the software. Even the processor intended for the product proved inadequate and involved a last minute hardware redesign. Many software redesigns, rewrites, and late additions had to be made, some based on results from user testing, some based on marketing considerations, and some based on systems considerations.
A Japanese language version of the system was produced in conjunction with Fuji Xerox (code named "J-Star") as well as full support for international customers.
In the end, there were many features from the Star Functional Specification that had to be left at the table. The product had to get to market and the last several months before release focused on reliability and performance.
System features
User interface
The key philosophy of the user interface was to mimic the office paradigm as much as possible in order to make it intuitive for users. The concept of WYSIWYG was considered paramount. Text would be displayed as black on a white background, just like paper, and the printer would replicate the screen using InterPress, a page description language developed at PARC.
The user would see a desktop that contained documents and folders, with different icons representing different types of documents. Clicking any icon would open a window. Users would not use programs (e.g. a text editor, graphics program or spreadsheet software), they would simply open the file and the appropriate application would appear.
The Star user interface was based on the concept of objects. For example in a word processing document, there would be page objects, paragraph objects, sentence objects, word objects and character objects. The user could select objects by clicking on them with the mouse, and press dedicated special keys on the keyboard to invoke standard object functions — Open, Delete, Copy and Move — in a uniform way. There was also a "Show Properties" key used to display settings, called property sheets, for the particular object (e.g. font size for a character object). These general conventions greatly simplified the menu structure of all the programs.
Object integration was designed into the system from the start. For example a chart object created in the graphing module could be inserted into any type of document. This type of capability eventually became available as part of the Operating System on the Apple Lisa and became part of Microsoft Windows with the introduction of OLE (Object Linking and Embedding) in 1990.
Hardware
Initially, the Star software was to run on a new series of virtual-memory processors, described in a PARC technical report called, "Wildflower: An Architecture for a Personal Computer", by Butler Lampson. The machines had names that always began with the letter 'D'.
The first of these machines was the Dolphin, built with TTL technology. The complexity of the software eventually overwhelmed its limited configuration; at one point in Star's development, it would take more than half an hour to reboot the system.
The next Star workstation hardware was known as a Dandelion (often shortened to "Dlion"). It had a microprogrammed CPU, based on the AMD Am2900 bitslice microprocessor technology, that implemented a virtual machine for the Mesa programming language. An enhanced version of the Dandelion (with more microcode space) was dubbed the "Dandetiger".
The base Dandelion system had 384KB memory (expandable to 1.5MB), a 10MB, 29MB or 40MB 8" hard drive, an 8" floppy drive, mouse and an Ethernet connection. The performance of this machine, which sold for $20,000, was about 850 in the Dhrystone benchmark — comparable to that of a VAX 11/750, which cost 5 times as much. The 17" CRT display (black and white, 1024x809 pixels with 38.7 Hz refresh) was large by standards at the time. It was meant to be able to display two 8.5"x11" pages side by side in actual size. An interesting feature of the display was that the overscan area (the borders) of it could be programmed with a 16x16 pattern. This was used to extend the root window pattern to all the edges of the monitor, a feature that is not available even today on most video cards.
The next design, the Dorado, used an ECL processor. It was 4 times faster than the Dandelion on standard benchmarks, and therefore competitive with the fastest super minicomputers of the day. A network router called Dicentra was also based on this design.
Marketing and commercial reception
The Xerox Star was not originally meant to be a stand-alone computer, but to be part of an integrated Xerox "personal office system" that also connected to other workstations and network services via Ethernet. Although a single unit sold for $16,000, a typical office would have to purchase at least 2 or 3 machines along with a file server and a name server/print server. Spending $50,000 to $100,000 for a complete installation was not an easy sell, when a secretary's annual salary was about $12,000 per year.
Later incarnations of the Star would allow users to purchase a single unit with a laser printer, but even so only about 25,000 units were sold, leading many to consider the Xerox Star to be a commercial failure.
The workstation was originally designed to run the Star software for performing office tasks, but it was also sold with different software for other markets. These other configurations included an Interlisp workstation, Smalltalk workstation, and a server.
Some have said that the Star was ahead of its time, that few outside of a small circle of developers really understood the potential of the system, considering that IBM introduced their 8088-based IBM PC running the comparatively primitive PC-DOS the same year that the Star was brought to market. However, comparison with the IBM PC may be irrelevant: well before it was launched, buyers in the Word Processing industry were aware of the 8086-based IBM Displaywriter, the full-page portrait black-on-white Xerox 850 page display system and the 120 page-per-minute Xerox 9700 laser printer. Furthermore, the design principles of Smalltalk and modeless working had been extensively discussed in the August 1981 issue of BYTE magazine, so Xerox PARC's standing and the potential of the Star can scarcely have been lost on its target (office systems) market, who would never have expected IBM to position a mass-market PC to threaten far more profitable dedicated WP systems. Unfortunately, the influential niche market of pioneering players in electronic publishing such as Longman were already aligning their production processes towards generic markup languages such as SGML (forerunner of HTML and XML) whereby authors using inexpensive offline systems could describe document structure, making their manuscripts ready for transfer to computer to film systems that offered far higher resolution than the then-current maximum of 360 dpi laser printing technologies.
Another possible reason given for the lack of success of the Star was the corporate structure of Xerox itself. A longtime copier company, Xerox played to their strengths. They already had one significant failure under their belt in making their acquisition of Scientific Data Systems pay off. It is said that there were internal jealousies between the old line copier systems divisions that were responsible for bulk of Xerox's revenues and the new upstart division. Their marketing efforts were seen by some as half-hearted or unfocused. Furthermore, the most technically savvy sales representatives that might have sold office automation equipment were paid large commissions on leases of laser printer equipment costing up to a half-million dollars. No commission structure for 'decentralized' systems could compete. The multi-lingual technical documentation market was also a major opportunity, but this required cross-border collaboration for which few sales organisations were ready at this time.
Probably most significantly, strategic planners at the Xerox Systems Group (XSG) did not feel that they could compete against other workstation manufacturers such as Apollo Computer or Symbolics. The Xerox name alone was considered their greatest asset, but it did not produce customers.
Finally, by today's standards, the system would be considered very slow, in part due to the limited hardware of the era, and in part due to a poorly implemented file system; saving a large file could take minutes. Crashes could be followed by an hours-long process called "file scavenging", signaled by the appearance of the diagnostic code '7511' in the top left corner of the screen.
In the end the Star's unsatisfactory commercial reception probably came down to price, performance in demonstrations, and weakness of sales channels. To give credit to Xerox, they did try many things in an attempt to jumpstart sales. The next release of Star was on a different, more efficient hardware platform, Daybreak, using a new, faster processor, and accompanied by significant rewriting of the Star software, renamed ViewPoint, to improve performance. The new system, dubbed the Xerox 6085 PCS , was released in 1985. The new hardware provided 1MB to 4MB of memory, a 10MB to 80MB hard disk, a 15" or 19" display, a 5.25" floppy drive, a mouse, Ethernet connector and a price of a little over $6,000.
The Xerox 6085 could be sold along with an attached laser printer as a standalone system. Also offered was a PC compatibility mode via an 80186-based expansion board. Users could transfer files between the ViewPoint system and PC-based software, albeit with some difficulty because the file formats were not compatible with any on the PC. But even with a significantly reduced price, it was still a Rolls Royce in the world of inexpensive $2,000 personal computers.
In 1989, Viewpoint 2.0 introduced many new applications related to desktop publishing. Eventually, Xerox jettisoned the integrated hardware/software workstation offered by Viewpoint and offered a software-only product called GlobalView, providing the Star interface and technology on an IBM PC compatible platform. The initial release required the installation of a MESA CPU add-on board. The final release of GlobalView 2.1 ran as an emulator on top of Microsoft Windows 3.1, Windows 95 or Windows 98 and was released in 1996.
Legacy
Even though the Star product failed to succeed in the marketplace, it raised expectations and laid important groundwork for the computers of today. Many of the innovations behind the Star, such as WYSIWYG editing, Ethernet, and network services such as Directory, Print, File, and internetwork routing have become commonplace in computers of today.
Members of the Apple Lisa engineering team saw Star at its introduction at the National Computer Conference (NCC '81) and returned to Cupertino where they converted their desktop manager to an icon-based interface modeled on the Star. Among the developers of the Gypsy editor, Larry Tesler left Xerox to join Apple in 1980 and Charles Simonyi left to join Microsoft in 1981 (whereupon Bill Gates spent $100,000 on a Xerox Star and laser printer), and several other defectors from PARC followed Simonyi to Microsoft in 1983.
Star, Viewpoint and GlobalView were the first commercial computing environments to offer support for most natural languages, including full-featured word processing, leading to their adoption by the Voice of America and other United States foreign affairs agencies as well as a number of multinational corporations.
The list of products that were inspired or influenced by the user interface of the Star include the Apple Lisa, Apple's Macintosh, GEM from Digital Research (the DR-DOS company), Microsoft Windows, Atari ST, BTRON from TRON Project, Commodore's Amiga, Elixir Desktop, Metaphor Computer Systems, Interleaf, Microsoft OS/2, OPEN LOOK (co-developed by Xerox), SunOS, KDE, Ventura Publisher and NEXTSTEP. Adobe Systems PostScript was based on InterPress. Ethernet was further refined by 3Com, and has become the standard networking protocol.
Some people feel that Apple, Microsoft, and others plagiarized the GUI and other innovations from the Xerox Star, and believe that Xerox didn't properly protect its intellectual property. The truth is more complicated. Many patent disclosures were in fact submitted for the innovations in the Star; however, at the time the 1975 Xerox Consent Decree, an FTC antitrust action, placed restrictions on what the company was able to patent. In addition, when the Star disclosures were being prepared, the Xerox patent attorneys were busy with several other new technologies such as laser printing. Finally, patents on software, particularly those relating to user interfaces, were an untested legal area at that time.
Xerox did go to trial to protect the Star user interface. In 1989, after Apple sued Microsoft for copyright infringement of its Macintosh user interface in Windows, Xerox filed a similar lawsuit against Apple; however, it was thrown out because a three year statute of limitations had passed. (Apple eventually lost its lawsuit in 1994, losing all claims to the user interface.)
See also
External links
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