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<META NAME="Author" Content="Steph Mineart">
<TITLE>Managing Multivendor Networks -- Ch 2 -- Digital Equipment Corporation</TITLE>
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<FONT COLOR="#000077">Managing Multivendor Networks</FONT></H1>
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<H1><FONT COLOR="#000077">- 2 -<BR>
Digital Equipment Corporation</FONT></H1>
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<UL>
<LI><A HREF="#Heading1">Company Background</A>
<LI><A HREF="#Heading2">Product Line Overview</A>
<UL>
<LI><A HREF="#Heading3">Digital Equipment Terminals</A>
<LI><A HREF="#Heading4">PCs</A>
<LI><A HREF="#Heading5">Engineering Workstations</A>
<LI><A HREF="#Heading6">Midrange Offerings</A>
<LI><A HREF="#Heading7">Top-End Offerings</A>
<LI><A HREF="#Heading8">Symmetric Multiprocessing and VMSclustering</A>
</UL>
<LI><A HREF="#Heading9">Strategy for Connectivity</A>
<LI><A HREF="#Heading10">Messaging</A>
<LI><A HREF="#Heading11">Application/User Relationship</A>
<LI><A HREF="#Heading12">Terminal Attachment Philosophy</A>
<LI><A HREF="#Heading13">Peer-to-Peer Relationships</A>
<LI><A HREF="#Heading14">PC Integration Strategy</A>
<LI><A HREF="#Heading15">Office Automation</A>
<LI><A HREF="#Heading16">Network Architecture</A>
</UL>
<P>
<HR SIZE="4">
</P>
<H2><A NAME="Heading1"></A><FONT COLOR="#000077">Company Background</FONT></H2>
<P>Digital Equipment Corporation (DEC) was founded in 1957 by three graduates of
Massachusetts Institute of Technology (MIT) operating out of an old mill in Maynard,
Massachusetts. One of the original three founders, Ken Olsen, went on to lead the
corporation and has been the most significant person to shape Digital. The fact that
the corporate headquarters remains in Maynard is representative of the company's
paradoxical commitment to both innovation and tradition.</P>
<P>During its early years, Digital produced specialized logic modules. Although it
operated in a data processing world dominated by large, mainframe-style computers,
Digital had the vision to pioneer minicomputers by introducing the PDP-1 in 1960.
The revolutionary aspect of the PDP-1 was its interactive video terminal capability--the
first such implementation of this now commonplace technology.</P>
<P>In 1970, Digital released the PDP-11, a 16-bit machine that became the most popular
design of the PDP series. Used most often in manufacturing and technical environments
for process and instrument control, the PDP-11 family remained in demand until it
was discontinued in 1991. Following the growth of the PDP-11 market, Digital released
a networking architecture in 1976 called the <I>Digital Network Architecture (DNA).</I>
The set of products and services defined by DNA is more commonly known as <I>DECnet</I>.
The PDP-11 design also served as the launching platform for another product: Digital's
general-purpose, 32-bit Virtual Address Extension (VAX) computer. Introduced in 1977,
the VAX gradually became Digital's premiere product--a building block for other products
offering performance and disk capacity similar to that of mainframes. Among these
products are VAX clusters, a computing environment released in 1983 and based on
multiple VAX computers sharing a common repository of disk space; and the mainframe-level
VAX 9000 Series, announced in 1989. In 1992, Digital released the Alpha AXP architecture,
based on 64-bit RISC microprocessors. Today, the Alpha runs on all Digital machines,
from PCs to high-end symmetric multiprocessing and clustered servers. Digital also
offers a line of high-end Pentium Pro products, including the four-processor Prioris
server and Celebris workstation.
<H2><A NAME="Heading2"></A><FONT COLOR="#000077">Product Line Overview</FONT></H2>
<P>Digital maintains a comprehensive manufacturing operation that designs and builds
most of its products. Having paved the way for the so-called midrange computer market,
Digital has expanded its product line up into the mainframe domain and down to the
PC playground. In support of these offerings, Digital produces a complete line of
terminals, printers, and assorted networking devices.</P>
<P>Digital's VAX family of computers ranged from the MicroVAX desktop system, all
the way up to high-end symmetric multi-processing (SMP) servers. Every member of
the VAX family supported the same operating systems and applications. The VAX family
was based on CMOS V technology and was highly scalable, up to symmetric multiprocessing
and clustering configurations. A number of different clustering options were possible
under the VAX architecture, including clustering in a single office, or clustering
systems that were geographically separated. However, the 32-bit nature of the VAX
architecture was quickly hitting the wall, primarily because of address limitations.</P>
<P>In 1988, Digital formed a task force to explore ways to preserve its existing
VAX VMS customer base through the coming decade, and in 1992, released the Alpha
AXP architecture. The Alpha AXP architecture retains many of the VAX's attributes
while offering significantly more power. The 32-bit VAX architecture was based on
complex instruction set computing (CISC), whereas the 64-bit Alpha AXP architecture
was reduced instruction set computer (RISC)-based. Digital subsequently ported its
OpenVMS operating system to the Alpha AXP architecture to enable OpenVMS applications
to take advantage of RISC's performance advantages.</P>
<P>The Alpha AXP architecture was designed for high-performance computing. In fact,
OpenVMS AXP applications outperform OpenVMS VAX applications by a factor of 3.59
to 1. Digital built easy migration capabilities to enable customers to move from
the VAX to the Alpha AXP architecture without significant recoding of their applications.
Digital's Alpha AXP processors run multiple operating systems and have the ability
to run native programs translated from VAX and MIPS architectures, thereby preserving
their customers' existing VAX and MIPS investments.</P>
<P>Digital's goals in developing the Alpha AXP architecture were to provide:
<UL>
<LI>High performance<BR>
<BR>
<LI>Longevity<BR>
<BR>
<LI>The ability to run both VMS and UNIX operating systems<BR>
<BR>
<LI>Easy migration from VAX and MIPS architectures
</UL>
<P>To operate OpenVMS AXP, DEC OSF/1 AXP, and Microsoft Windows NT operating systems,
Digital adopted some technology from their PRISM design. Under this model, a set
of sub-routines (PALcodes) with controlled entry points were established for each
operating system. For running VAX and MIPS binary images, Digital uses binary translation.</P>
<P>The Alpha AXP architecture is based on a shared-memory model. The first implementation
was the DECchip 21064 microprocessor. At the time of its release in 1992, it was
the world's fastest single-chip microprocessor--even listed in the <I>Guinness Book
of Records</I> as such. The latest implementation, the 21164 Alpha microprocessor,
runs at a blazingly fast 300MHz, and power can be increased further through symmetric
multiprocessing or clustering. The Alpha AXP chip is capable of running multiple
operating systems, and can run native programs translated from VAX and MIPS architectures.</P>
<P>The Alpha AXP architecture is now used throughout Digital's product line. The
Alpha AXP's 64-bit architecture is designed with an eye towards high performance,
and continues Digital's focus on multiple processors. The powerful 64-bit Alpha architecture
is capable of bringing high-end features to smaller systems. The Alpha systems can
run Digital UNIX, OpenVMS, and Windows NT; for sophisticated functions such as data
warehousing, they can address massive files greater than 2G in size.</P>
<P>Digital released a 64-bit version of its Digital UNIX operating system in March,
1996. Digital UNIX 4.0 integrates the now pervasive <I>Common Desktop Environment
(CDE) GUI,</I> which establishes a common look and feel between all major UNIX implementations.
Digital UNIX 4.0 supports POSIX threads, real-time standards, and X11R6. Additionally,
it conforms fully to the Single UNIX Specification (Spec1170) administered by the
X/Open organization. The 64-bit nature of version 4.0 now enables Digital UNIX to
run high-end applications such as data warehousing.
<H3><A NAME="Heading3"></A><FONT COLOR="#000077">Digital Equipment Terminals</FONT></H3>
<P>The Digital line of terminals is perhaps the most widely emulated line of character-oriented
displays. The reasons are straightforward:
<UL>
<LI>Digital does an excellent job of providing ANSI compatibility, which enables
Digital terminals to be used in environments that might not include Digital computer
systems.<BR>
<BR>
<LI>The widespread use of the Digital PDP and VAX computer systems has enabled the
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