A number of products today from several vendors have adopted the nomenclature "workstation" and the intended users of these products range from secretaries and draftsmen to company vice presidents and chairmen of the board. Making these products suitable to meet the specifications of the ORB IWS would require major design modifications to the existing "workstation" product. Some small systems would require additional functionality and performance, or in some cases features from several systems would have to be merged in a new product. In other cases a larger machine with a superset of functionality would require reduction in delivered capability in orter to effectively compete for this requirement.Other products are currently in design and are awaiting initial product announcement. The APOLLO workstation architecture is totally apart from that environment. From the time of APOLLO's incorporation in February, 1980, the design goals for the network/workstation architecture have not changed. From the company's inception, the intended use of the product was as a high performance graphics workstation for technical professionals in the environment of an integrated local area network. DOMAIN, APOLLO's name for this integrated workstation network system, was announced two years ago, in November 1980. In the traditional sense, the DOMAIN system is not really a "network" at all. The term "network" usually implies a system of scattered computers and terminals, tied together by low-performance communica- tion lines. Because moving information across them has been clumsy, slow, and expensive, traditional networks have been pre-occupied with layers of communications protocols. In contrast, the DOMAIN network is a token-passing, base-band, high-speed, local bus with communication at 12 megabits per second, the speed you would expect for workstation internal operations. A DOMAIN system is an integrated computer environment, consisting of from as few as one to as many as several hundred nodes, tied together by a high-speed, base-band, communications network. Each workstation is a powerful, 32-bit computer, with up to 3.5 megabytes of main memory, sophisticated multi-window graphics capabilities, optional disk and peripherals, and the ability to support multiple concurrent processes, with each process having a virtual address space of up to 16 megabytes. In addition, each workstation after satisfying the proper access security, has high speed access to data and programs stored at any other workstation, with the same access rate as if these data and programs were local. - DOMAIN systems offer a wide range of capabilities, including: - Power to run mainframe-scale FORTRAN programs, - High resolution graphics, closeley-integrated for maximum performance, - A high-speed local area network architecture, providing economical resource sharing, low entry cost, and incremantal growth, - A compatible growth path, providing long-term protection for users' investments in application software and peripheral hardware as the DOMAIN technology advances. - High system availability and ease of maintenance. More specifically, each DOMAIN workstation includes a state-of-the-art, 32-bit processor; from .5 to 3.5 megabytes of main memory, implemented with advanced 64 kilobit RAM technology, with error checking and corr- ection (ECC) as a standard feature; optional dedicated high-speed disk drives, line printers, and other peripherals; and a network-wide virtual memory operating system (AEGIS) supporting up to 15 concurrent processes per node, each process able to address up to 16 megabytes of virtual memory. This allows DOMAIN users to take on a wide range of demanding graphics and computation-oriented applications. Workstation computing power is extended by the performance enhancement module. The module contains both a cache memory and a floating point processor on a single circuit board. The 4-kilobyte cache memory reduces effective memory cycle time, so the processor spends less time waiting for instructions and data fetches. The floating point processor portion of the performance enhancement module provides single precision (32 bits) and double precision (64 bits) floating point arithmetic functions, plus several special-purpose instr- uctions, including register-state save and restore, and a polynomial evaluation primitive. For high-speed on-line mass storage, disk units are available in 34MB, 68MB, and 158MB Winchester drives and 300MB Storage Module Devices. Each of the DOMAIN bit-mapped, raster-scan displays incorporates an independent RAM memory; 128 kilobytes for the monochromatic displays and one or optional two megabytes for the color display. The contents of RAM memory are directly mapped onto a high-resolution screen for detailed presentation of both character fonts and graphic images. Each point on the screen is represented individually in RAM memory. The screen is constantly refreshed, and changes in the bit-map memory are instantaneously displayed on the display screen. A complete new screen can be constructed in as little as a fraction of a second. This bit-map memory is directly addressable by the CPU, allowing programs to easily modify its contents. However, the display controller is a separate device on the node's internal bus, so the display can be re- freshed while the CPU is running. The bit-mapped display supports multiple windows, which can be present- ed side by side or overlaid in whole or in part. The display manager allows any window to be brought into full view instantly. This window- ing capability allows the operating system to support multiple command environments simultaneously. Separate windows provide "virtual terminals" connected to multiple programs and data. Because there is no need to wait for one program's completion before starting to work with another, it is possible to move from one window -and one program context - to another with complete freedom. The new mode of concurrent interaction saves precious time not only in normal operation, but also in the software development cycle. Two monochromatic DOMAIN display screens are availble: a 19-inch hori- zontally oriented (landscape) display, and a 15-inch, vertically-oriented (portrait) display. Each display has a visible field of 800 x 1024 pixels. For user comfort, each screen has a brightness control, and produces either a black-on-white or white-on-black, reverse image display. The displays are free standing units, the can be set up as far as 3 meters from the main DOMAIN node cabinet, so system users have consid- erable freedom in setting up work areas for their own efficiency. The third DOMAIN display is a 19-inch, highly interactive, square format color monitor that incorporates all of the features of the monochromatic displays, plus a long list of others, including: high resolution 1024 x 1024 pixel display, with each pixel 4, 8 or 24 bits deep (supporting 16, 256, or 262,000 colors); up to 2MB of dedicated display memory; hardware raster ops; hardware pan and zoom; area fills; high-performance vector generation; and a 20 megabits/sec/plane high speed memory to memory transfer (Bit BLT) capability. All of the DOMAIN displays include a keyboard with 28 user-programmable keys. Eight of these are special function keys that can be defined by the user for each virtual terminal. The AEGIS operating system is an advanced, network-wide virtual-memory operating system, geared to supporting DOMAIN's multi-level, highly interactive operations. It is unique in that it takes the concepts of a virtual memory operating system, supporting multiple, concurrent pro- cesses, and extends these concepts from a single user context across the entire DOMAIN network, which may encompass hundreds of users. The key to this breakthrough in virtual memory operating systems is the fact that the AEGIS operating system is an "object-oriented" operating system. That is, it treats each element in the system environment - programs, data, files, records, peripherals, etc. - as a unique object. More-over, the system assigns to each object a unique, 64-bit identifier. This 64-bit identifier code gives the operating system the ability to assign unique names to every object ever created on any DOMAIN network. It is this capability that allows the AEGIS operating system to support literally thousands of concurrent processes in an orderly, efficient fashion. The high-productivity DOMAIN programming environment includes ANSI- standard Fortran 77, Pascal, and C, a wide range of standardized soft- ware tools, and a highly consistent, yet flexible, command environment. DOMAIN's standardized software tools allow programmers to develop large, complex programs by piping data through many smaller, simpler programs, with the output of one small program becoming the input for the next. Large programs can be built faster and at lower cost, and debugging and program updating are far simpler for the life of the program. DOMAIN's powerful graphics capabilities are enormously useful in prog- ram development. Instead of plodding along in the conventional edit- compile-debug sequence, the programmer can use DOMAIN's powerful screen editor to view separate windows for each function and move freely from task to task, from environment to environment, comparing, cross-referenc- ing, and updating, without obliterating context. Other key software support capabilities include: an advanced high-level language debugger; IBM 3270 communications support; asynchronous ASCII terminal emulation; a powerful font editor allowing users to interact- ively create and modify character sets and graphic symbols; 44 graphics primitives callable from user programs, including raster-ops; full supp- ort of the CORE graphics package, the proposed device independent stand- ard for interactive graphics; a flexible interprocess communications facility; support for remote diagnostics; an on-line HELP! facility; and floating-point hardware and cache memory support. The DOMAIN system also supports its own fully integrated distributed database management system. It is an essential part of the DOMAIN environment: the system was designed from the inside out to be a dis- tributed database management system. Its unique peer network and con- currency control provide an orderly environment for the management of a distributed database. This is in sharp contrast to most database systems, which often have inadequate facilities for dealing with in- formation that is critical in a distributed environment - "who created this data?" ; "where is the data I need? "; "who has updated it? "; and "which is the master copy". In addition to the APOLLO software described above, a growing library of third party software can provide support for scientific, engineering modeling, CAD/CAM, anad decision support applications. The DOMAIN system has been designed around a high-level architecture that makes it far less susceptible to technological obsolescence than other systems. Today, DOMAIN uses advanced, 32-bit microprocessor tech- nology, but the organization of the system transcends currently avail- able chip-level architecture. DOMAIN users will be able to move from today's technology without abandoning their current investment in soft- ware. Similarly, the DOMAIN network is independent of the particular communications technology with which it is implemented. Although DOMAIN networks currently use coaxial cable connections between nodes, the DOMAIN architecture will allow future use of fiber optics, laser, infrared, or microwave transmission technology.