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40-524: The initial development of Unix occurred on DEC equipment, notably DEC PDP-7 and PDP-11 (Programmable Data Processor) systems. Later DEC computers, such as their VAX, also offered Unix. The first port to VAX, UNIX/32V , was finished in 1978, not long after the October 1977 announcement of the VAX, for which – at that time – DEC only supplied its own proprietary operating system, VMS . DEC's Unix Engineering Group (UEG)

80-409: A combination hardware and software product named Prestoserv which accelerated NFS file serving to allow better performance for diskless workstations to communicate to a file serving Ultrix host. The kernel supported symmetric multiprocessing while not being fully multithreaded based upon pre-Ultrix work by Armando Stettner and earlier work by George H. Goble at Purdue University. As such, there

120-576: A native UNIX product, Stettner and Bill Doll presented plans for DEC to make a native VAX Unix product available to its customers; DEC founder Ken Olsen agreed. DEC's first native UNIX product was V7M (for modified) or V7M11 for the PDP-11 and was based on Version 7 Unix from Bell Labs. V7M was developed by DEC's original Unix Engineering Group (UEG); work was done primarily by Fred Canter and Jerry Brenner, with their teammates Stettner, Bill Burns, Mary Anne Cacciola, and Bill Munson. V7M contained many fixes to

160-564: A network management architecture, and gateways to other types of networks including IBM's SNA and CCITT Recommendation X.25 . CTERM: Command Terminal MOP: Maintenance Operations Protocol Phase IV and Phase IV+ (1982). Phase IV was released initially to RSX-11 and VMS systems, later TOPS-20 , TOPS-10 , ULTRIX , VAXELN , and RSTS/E gained support. Support for networks of up to 64,449 nodes (63 areas of 1023 nodes) with 16-bit addresses, datalink capabilities expanded beyond DDCMP to include Ethernet local area network support as

200-486: A new network management model, local or distributed name service, improved performance over Phase IV. Move from a proprietary network to an Open Systems Interconnection (OSI) by integration of ISO standards to provide multi-vendor connectivity and compatibility with DNA Phase IV, the last two features resulted in a hybrid network architecture (DNA and OSI) with separate "towers" sharing an integrated transport layer. Transparent transport level links to TCP/IP were added via

240-573: A second PDP-7A (serial number 113) previously located at the University of Oregon in its Nuclear Physics laboratory is now at the Living Computer Museum in Seattle, Washington and is completely restored to running condition after being disassembled for transport; Another PDP-7 (serial number 47) is known to be in the collection of Max Burnet near Sydney, Australia, a fourth PDP-7 (serial number 33)

280-467: Is 4K words (9 KB) but expandable up to 64K words (144 KB). The PDP-7 weighs about 1,100 pounds (500 kg). DECsys , the first operating system for DEC's 18-bit computer family (and DEC's first operating system for a computer smaller than its 36-bit timesharing systems), was introduced in 1965. It provides an interactive, single user, program development environment for Fortran and assembly language programs. In 1969, Ken Thompson wrote

320-627: Is in storage at the Computer History Museum in Mountain View, California and a fifth PDP-7 (serial number 129) belonging to Fred Yerian is also located at the Museum, and has been demonstrated running Unix version 0 and compiling a B program . DECnet DECnet is a suite of network protocols created by Digital Equipment Corporation . Originally released in 1975 in order to connect two PDP-11 minicomputers , it evolved into one of

360-538: The IETF RFC 1006 (OSI over IP) and RFC 1859 (NSP over IP) standards (see diagram) . It was later renamed DECnet/OSI to emphasize its OSI interconnectability, and subsequently DECnet-Plus as TCP/IP protocols were incorporated. DEC's internal corporate network was a DECnet network called Easynet, which had evolved from DEC's Engineering Net (E-NET). It included over 2,000 nodes as of 1984, 15,000 nodes (in 39 countries) as of 1987, and 54,000 nodes as of 1990. DECnet

400-973: The RSX-11 operating system, or a small number of PDP-8s running the RTS-8 operating system, with communication over point-to-point ( DDCMP ) links between nodes. Phase II (1975) Support for networks of up to 32 nodes with multiple, different implementations which could inter-operate with each other. Implementations expanded to include RSTS , TOPS-10 , TOPS-20 and VAX/VMS with communications between processors still limited to point-to-point links only. Introduction of downline loading (MOP), and file transfer using File Access Listener (FAL), remote file access using Data Access Protocol (DAP), task-to-task programming interfaces and network management features. Phase III (1980). Support for networks of up to 255 nodes with 8-bit addresses, over point-to point and multi-drop links. Introduction of adaptive routing capability, record access,

440-492: The DIGITAL Network Architecture. To trace the evolution of DECnet is to trace the development of DNA. The beginnings of DNA were in the early 1970s. DIGITAL published its first DNA specification at about the same time that IBM announced its Systems Network Architecture (SNA). Since that time, development of DNA has evolved through the following phases: Phase I (1974) Support limited to two PDP-11s running

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480-476: The OSI physical and datalink layers with DECnet and LAT terminal servers used MOP for the server image download and related bootstrap processing. Enhancements made to DECnet Phase IV eventually became known as DECnet Phase IV+, although systems running this protocol remained completely interoperable with DECnet Phase IV systems. Phase V and Phase V+ (1987). Support for very large (architecturally unlimited) networks,

520-580: The PATHWORKS 32 client, that implemented much of DECnet Phase IV for DOS, and 16 and 32 bit Microsoft Windows platforms (all the way through to Windows Server 2003). Phase IV implemented an 8 layer architecture similar to the OSI (7 layer) model especially at the lower levels. Since the OSI standards were not yet fully developed at the time, many of the Phase IV protocols remained proprietary. The Ethernet implementation

560-478: The best from System V and added it to a BSD base. Originally, on the VAX workstations, Ultrix-32 had a desktop environment called UWS, Ultrix Worksystem Software, which was based on X10 and the Ultrix Window Manager . Later, the widespread version 11 of the X Window System (X11) was added, using a window manager and widget toolkit named XUI (X User Interface), which was also used on VMS releases of

600-486: The datalink of choice, expanded adaptive routing capability to include hierarchical routing (areas, level 1 and level 2 routers), VMScluster support (cluster alias) and host services (CTERM). CTERM allowed a user on one computer to log into another computer remotely, performing the same function that Telnet does in the TCP/IP protocol stack. Digital also released a product called the PATHWORKS client, and more commonly known as

640-534: The engineering work was in making the systems relatively flexible and configurable despite their binary-only nature. DEC provided Ultrix on three platforms: PDP-11 minicomputers (where Ultrix was one of many available operating systems from DEC), VAX-based computers (where Ultrix was one of two primary OS choices) and the Ultrix-only DECstation workstations and DECsystem servers. Note that the DECstation and

680-447: The first UNIX system, then named Unics as a pun on Multics despite only using two design elements from Multics, in assembly language on a PDP-7, as the operating system for Space Travel , a game which requires graphics to depict the motion of the planets. A PDP-7 was also the development system used during the development of MUMPS at MGH in Boston a few years earlier. The PDP-7

720-536: The first peer-to-peer network architectures, thus transforming DEC into a networking powerhouse in the 1980s. Initially built with three layers , it later (1982) evolved into a seven-layer OSI -compliant networking protocol. DECnet was built right into the DEC flagship operating system OpenVMS since its inception. Later Digital ported it to Ultrix , OSF/1 (later Tru64 ) as well as Apple Macintosh and IBM PC running variants of DOS , OS/2 and Microsoft Windows under

760-510: The initial development of the Alpha architecture, but was never released as a product. Later, DEC replaced Ultrix with OSF/1 on Alpha , ending Unix development on the MIPS and VAX platforms. The last major release of Ultrix was version 4.5 in 1995, which supported all previously supported DECstations and VAXen. There were some subsequent Y2K patches. WordMARC , a scientifically oriented word processor,

800-446: The kernel including support for separate instruction and data spaces, significant work for hardware error recovery, and many device drivers. Much work was put into producing a release that would reliably bootstrap from many tape drives or disk drives. V7M was well respected in the Unix community. UEG evolved into the group that later developed Ultrix. The first native VAX UNIX product from DEC

840-482: The later DECsystem products (as opposed to DEC's original DECsystem line) used MIPS processors and predate the much later Alpha -based systems. The V7m product was later renamed to Ultrix-11 to establish the family with Ultrix-32 , but as the PDP-11 faded from view Ultrix-32 became known simply as Ultrix . When the MIPS versions of Ultrix was released, the VAX and MIPS versions were referred to as VAX/ULTRIX and RISC/ULTRIX respectively. Much engineering emphasis

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880-507: The name PATHWORKS , allowing these systems to connect to DECnet networks of VAX machines as terminal nodes. While the DECnet protocols were designed entirely by Digital Equipment Corporation, DECnet Phase II (and later) were open standards with published specifications, and several implementations were developed outside DEC, including ones for FreeBSD and Linux . DECnet code in the Linux kernel

920-437: The notable exception of RT-11 . DECnet stacks are found on Linux, SunOS and other platforms, and Cisco and other network vendors offer products that can cooperate with and operate within DECnet networks. Full DECnet Phase IV specifications are available. At the same time that DECnet Phase IV was released, the company also released a proprietary protocol called LAT for serial terminal access via Terminal servers . LAT shared

960-488: The operations staff at the various sites, all of which were using a variety of DEC computers. As of March 1983, it included Columbia University , Carnegie Mellon University , and Case Western Reserve University . By May 1986, New York University , Stevens Institute of Technology , Vassar College and Oberlin College had been added. Several other universities joined later. Hobbyist DECnet networks have been in use during

1000-722: The standard TCP/IP , and both the SMTP and DEC's Mail-11 protocols. Notably, Ultrix implemented the inter-process communication (IPC) facilities found in System V ( named pipes , messages , semaphores , and shared memory ). While the converged Unix from the Sun and AT&T alliance (that spawned the Open Software Foundation or OSF), released late 1986, put BSD features into System V, DEC, as described in Stettner's original Ultrix plans, took

1040-460: The tape Bill Joy took with him. The thinking was that 5BSD would be the next version - university lawyers thought it would be better to call it 4.1BSD. After the completion of 4.1BSD, Bill Joy left Berkeley to work at Sun Microsystems . Shannon later moved from New Hampshire to join him. Stettner stayed at DEC and later conceived of and started the Ultrix project. Shortly after IBM announced plans for

1080-580: The time. Eventually Ultrix also provided the Motif toolkit and Motif Window Manager . Ultrix ran on multiprocessor systems from both the VAX and DECsystem families. Ultrix-32 supported SCSI disks and tapes and also proprietary Digital Storage Systems Interconnect and CI peripherals employing DEC's Mass Storage Control Protocol , although lacking the OpenVMS distributed lock manager it did not support concurrent access from multiple Ultrix systems. DEC also released

1120-529: The time. The PDP-7 is the third of Digital's 18-bit machines, with essentially the same instruction set architecture as the PDP-4 and the PDP-9 . The PDP-7 was the first wire-wrapped PDP computer. The computer has a memory cycle time of 1.75 µs and an add time of 4 µs . Input/output (I/O) includes a keyboard, printer, punched tape and dual transport DECtape drives (type 555). The standard core memory capacity

1160-583: The use of either "poor man's routing" (PMR) or address translation gateways. In December 1988, VAX/VMS hosts on the DECnet Internet were attacked by the Father Christmas worm . CCNET (Computer Center Network) was a DECnet network that connected the campuses of various universities in the eastern regions of the United States during the 1980s. A key benefit was the sharing of systems software developed by

1200-399: Was POSIX compliant. Shannon and Stettner worked on low-level CPU and device driver support initially on UNIX/32V but quickly moved to concentrate on working with the University of California, Berkeley 's 4BSD . Berkeley's Bill Joy came to New Hampshire to work with Shannon and Stettner to wrap up a new BSD release. UEG's machine was the first to run the new Unix, labeled 4.5BSD as was

1240-879: Was Ultrix-32, based on 4.2BSD with some non-kernel features from System V , and was released in June 1984. Ultrix-32 was primarily the brainchild of Armando Stettner. It provided a Berkeley-based native VAX Unix on a broad array of hardware configurations without the need to access kernel sources. A further goal was to enable better support by DEC's field software and systems support engineers through better hardware support, system messages, and documentation. It also incorporated several modifications and scripts from Usenet/UUCP experience. Later, Ultrix-32 incorporated support for DECnet and other proprietary DEC protocols such as LAT . It did not support VAXclustering . Given Western Electric /AT&T Unix licensing, DEC (and others) were restricted to selling binary-only licenses. A significant part of

Ultrix - Misplaced Pages Continue

1280-459: Was among the application packages available for Ultrix. The following shells were provided with Ultrix: PDP-7 The PDP-7 is an 18-bit minicomputer produced by Digital Equipment Corporation as part of the PDP series. Introduced in 1964, shipped since 1965, it was the first to use their Flip-Chip technology. With a cost of US$ 72,000 , it was cheap but powerful by the standards of

1320-592: Was described as "highly successful." A combined total of 120 of the PDP-7 and PDP-7A were sold. A DEC publication states that the first units shipped to customers in November 1964. Eleven systems were shipped to the UK. At least four PDP-7s were confirmed to still exist as of 2011 and a fifth was discovered in 2017. A PDP-7A (serial number 115) was under restoration in Oslo , Norway;

1360-505: Was liberal use of locking and some tasks could only be done by particular CPUs (e.g. the processing of interrupts ). This was not uncommon in other SMP implementations of that time (e.g. SunOS ). Also, Ultrix was slow to support many then new or emerging Unix system capabilities found on competing Unix systems (e.g. it never supported shared libraries or dynamically linked executables); and a delay in implementing bind, 4.3BSD system calls and libraries. The absence of memory-mapped file support

1400-743: Was marked as orphaned on February 18, 2010 and removed August 22, 2022. DECnet refers to a specific set of hardware and software networking products which implement the DIGITAL Network Architecture (DNA). The DIGITAL Network Architecture has a set of documents which define the network architecture in general, state the specifications for each layer of the architecture, and describe the protocols which operate within each layer. Although network protocol analyzer tools tend to categorize all protocols from DIGITAL as "DECnet", strictly speaking, non-routed DIGITAL protocols such as LAT , SCS, AMDS, LAST/LAD are not DECnet protocols and are not part of

1440-439: Was placed on supportability and reliable operations including continued work on CPU and device driver support (which was, for the most part, also sent to UC Berkeley), hardware failure support and recovery with enhancement to error message text, documentation, and general work at both the kernel and systems program levels. Later Ultrix-32 incorporated some features from 4.3BSD and optionally included DECnet and SNA in addition to

1480-456: Was regarded as a particular deficiency with Ultrix in comparison to its competitors in the early 1990s. As part of its commitment to the OSF, Armando Stettner went to DEC's Cambridge Research Labs to work on the port of OSF/1 to DEC's RISC-based DECstation 3100 workstation. This was released in 1991 with a Mach -based kernel for the MIPS architecture. A port of Ultrix to Alpha was carried out during

1520-499: Was started by Bill Munson with Jerry Brenner and Fred Canter, both from DEC's Customer Service Engineering group, Bill Shannon (from Case Western Reserve University ), and Armando Stettner (from Bell Labs ). Other later members of UEG included Joel Magid, Bill Doll, and Jim Barclay recruited from DEC's marketing and product management groups. Under Canter's direction, UEG released V7M , a modified version of Unix 7th Edition (q.v.). In 1988 The New York Times reported that Ultrix

1560-638: Was unusual in that the software changed the physical address of the Ethernet interface on the network to AA-00-04-00-xx-yy where xx-yy reflected the DECnet network address of the host. This allowed ARP-less LAN operation because the LAN address could be deduced from the DECnet address. This precluded connecting two NICs from the same DECnet node onto the same LAN segment, however. The initial implementations released were for VAX/VMS and RSX-11, later this expanded to virtually every operating system DIGITAL ever shipped with

1600-533: Was used at various scientific research centers which linked their networks to form an international network called the DECnet Internet. This included the U.S. Space Physics Analysis Network (US-SPAN), the European Space Physics Analysis Network (E-SPAN), Energy Sciences Network , and other research and education networks. The network consisted of over 17,000 nodes as of 1989. Routing between networks with different address spaces involved

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