Windows NT 3.1
Encyclopedia
Windows NT 3.1 is the first release of Microsoft
's Windows NT
line of server
and business desktop operating system
s, and was released to manufacturing on 27 July 1993. The version number was chosen to match the one of Windows 3.1
, the then-latest operating environment
from Microsoft
, on account of the similar visual appearance of the user interface. Two editions of NT 3.1 were made available, Windows NT 3.1 and Windows NT Advanced Server. It was succeeded by Windows NT 3.5
in September 1994.
It could run on Intel x86, DEC Alpha
, and MIPS R4000
CPUs
.
led by Dave Cutler
. Many elements of the design reflect earlier DEC experience with VMS and RSX-11
. The operating system was designed to run on multiple instruction set architectures and multiple hardware platforms within each architecture. The platform dependencies are largely hidden from the rest of the system by a kernel mode module called the HAL.
Windows NT was originally intended to be OS/2
3.0, the third version of the operating system developed jointly by Microsoft and IBM. When Windows 3.0
was released in May 1990, it was so successful that Microsoft decided to change the primary application programming interface
for the still-unreleased NT OS/2 (as it was then known) from an extended OS/2 API to an extended Windows API
. This decision caused tension between Microsoft and IBM, and the collaboration ultimately fell apart. IBM continued OS/2 development alone, while Microsoft continued work on the newly-renamed Windows NT.
The first public demonstration of Windows NT, at the time called "Windows Advanced Server for LAN Manager", was at a developer conference in August 1991, and the product was formally announced at the Spring 1993 COMDEX
in Atlanta
, Georgia
.
Application programming interface
s in Windows NT are implemented as subsystems atop the undocumented Native API
; it was this that allowed the late adoption of the Windows API. Windows NT was the first operating system by Microsoft to use Unicode
internally. Windows NT introduced the Win32 API, a 32-bit implementation of the 16-bit Windows API. Most 16-bit Windows applications could be ported to the new system with minimal changes and a recompile. Win32 also provided native API support for many new features, such as networking and multithreading.
The project had a codename of just "NTOS", which is preserved in the filename of the Windows NT kernel, ntoskrnl.exe.
Since it was targeted to become the next version of OS/2, a more official name of the project was "NT OS/2". This name is preserved up to now in some Windows NT driver development kit files.
and C++
. Any differences in core hardware architecture that could not be resolved by a simple recompile (e.g., memory architecture, multi/uniprocessor support) were offloaded to the HAL.
Also, NT's boot architecture borrowed heavily from the ARC
initiative, particularly on non-x86 platforms.
CPU, codenamed N10 (or "N-Ten").
However, the i860 was "horribly behind schedule", so the NT team used an emulator before i860 prototype systems designed in-house (code-named Dazzle) were available. Support for the other platforms followed later and no public release of NT for i860 systems was made. The rationale for targeting the i860 first was to improve portability and avoid producing an x86-centric design.
processor; specifically MIPS systems following the Advanced RISC Computing
(ARC) specification.
processor. However, because the Alpha itself was delayed, Microsoft's developers did not have access to production Alpha machines to develop on until shortly before NT shipped. Consequently, NT did not initially ship with Alpha support out of the box: the first packages of NT included a mail-in coupon to receive a free CD of NT 3.1 with Alpha support.
" (aka WOW), which allowed most Windows 3.x applications to run unmodified on NT. Applications which made direct access to hardware, or depended on DOS-level drivers, were not supported.
In NT 3.1, all 16-bit applications ran within a single WOW process. This meant that a single badly behaving 16-bit application could shut down the WOW session (and any other 16-bit applications running). However, the operating system itself was insulated, so the WOW process could simply be killed and restarted — a significant step forward for Windows' stability.
, further solidifying its role as Microsoft transitioned users off of the 16-bit platform.
Win32 is a comprehensive API, offering OS services ranging from memory management to UI access. NT prevents all user-level applications from directly accessing hardware. This increases system reliability, at the cost of performance. However, this also means that virtually all Win32 applications relied exclusively on the C/C++ Win32 API; the upshot is that porting such an application to another NT-supported system architecture (e.g., moving from x86 NT to MIPS NT) usually required no more than a recompile (some applications might require minor tweaking, such as if assumptions were made in code about endianness
).
OS/2
Though "NT OS/2" was finally released as "Windows NT", it is largely compatible with HPFS disk volumes and the x86 version supports character-mode
16-bit OS/2 applications. Many of the OS/2 APIs (particularly NetBIOS/LANMan networking APIs) already existed in almost identical forms in both 16-bit OS/2 and DOS/Windows, so these were incorporated into the Win32 API. For most 16-bit OS/2 programs, minimal code changes were necessary to recompile as NT console
applications
.
OS/2 and Windows also share the concept of Dynamic-Link Libraries
(DLLs). Although the implementation varies somewhat between Windows and OS/2 DLLs, this additional similarity meant that even complex OS/2 applications could usually be converted to NT with little change to the overall design.
-compatible. This was added largely to help spur sales in US government contracts, as many government agencies mandated POSIX compatibility for consideration.
Note that POSIX compatibility is an API-level requirement. That is, one POSIX operating system won't necessarily be able to execute binary files compiled for a different system, even though both are POSIX compliant. POSIX simply specifies that the source code should compile correctly for each system.
The POSIX subsystem in NT 3.1 primarily provided support for UNIX-style file system permissions and long filename
s (including permitting filename characters that are otherwise illegal for Windows files, and denying some that are normally legal).
starting with IE2
, and released up to Internet Explorer 5.0
for Windows NT 3.x. Also, a IE 1.5 supported NT, but this patch was actually released after IE2 came out.
API), TCP/IP, and DLC
.
/IBM LAN Server networks. In NT 3.1, it was the only supported protocol for networking with legacy LAN Manager networks, as well as other NT systems. Using NBF, NT could participate in file/print sharing, and NT Advanced Server could act as a Domain Controller
(even sharing DC duties with OS/2 LAN Manager servers).
. This was replaced in NT 3.5 with a new stack developed in-house.
The TCP/IP stack included WinSock
and STREAMS
support, but it was not supported for networking among Microsoft LAN Manager or NT systems. Also, DHCP was not available, so IP addresses had to be manually configured. Support for NBT, DHCP, and WINS was added in NT 3.5.
JetDirect
interface. It could also be used by Microsoft SNA Server
for communication with IBM mainframe
systems.
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
's Windows NT
Windows NT
Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
line of server
Server (computing)
In the context of client-server architecture, a server is a computer program running to serve the requests of other programs, the "clients". Thus, the "server" performs some computational task on behalf of "clients"...
and business desktop operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s, and was released to manufacturing on 27 July 1993. The version number was chosen to match the one of Windows 3.1
Windows 3.1x
Windows 3.1x is a series of 16-bit operating systems produced by Microsoft for use on personal computers. The series began with Windows 3.1, which was first sold during March 1992 as a successor to Windows 3.0...
, the then-latest operating environment
Operating environment
The operating environment in engineering describes the circumstances surrounding and potentially affecting something that is operating. For example electronic or mechanical equipment may be affected by high temperatures, vibration, dust, and other parameters which comprise the operating...
from Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
, on account of the similar visual appearance of the user interface. Two editions of NT 3.1 were made available, Windows NT 3.1 and Windows NT Advanced Server. It was succeeded by Windows NT 3.5
Windows NT 3.5
Windows NT 3.5 is the second release of the Microsoft Windows NT operating system. It was released on 21 September 1994.One of the primary goals during Windows NT 3.5's development was to increase the speed of the operating system; as a result, the project was given the codename "Daytona" in...
in September 1994.
It could run on Intel x86, DEC Alpha
DEC Alpha
Alpha, originally known as Alpha AXP, is a 64-bit reduced instruction set computer instruction set architecture developed by Digital Equipment Corporation , designed to replace the 32-bit VAX complex instruction set computer ISA and its implementations. Alpha was implemented in microprocessors...
, and MIPS R4000
MIPS architecture
MIPS is a reduced instruction set computer instruction set architecture developed by MIPS Technologies . The early MIPS architectures were 32-bit, and later versions were 64-bit...
CPUs
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
.
Development
Development of Windows NT started in November 1988, after Microsoft hired a group of developers from Digital Equipment CorporationDigital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
led by Dave Cutler
Dave Cutler
David Neil Cutler, Sr. is an American software engineer, designer and developer of several operating systems including RSX-11M, VMS and VAXELN at Digital Equipment Corporation and Windows at Microsoft.- Personal history :...
. Many elements of the design reflect earlier DEC experience with VMS and RSX-11
RSX-11
RSX-11 is a family of real-time operating systems mainly for PDP-11 computers created by Digital Equipment Corporation , common in the late 1970s and early 1980s. RSX-11D first appeared on the PDP-11/40 in 1972...
. The operating system was designed to run on multiple instruction set architectures and multiple hardware platforms within each architecture. The platform dependencies are largely hidden from the rest of the system by a kernel mode module called the HAL.
Windows NT was originally intended to be OS/2
OS/2
OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
3.0, the third version of the operating system developed jointly by Microsoft and IBM. When Windows 3.0
Windows 3.0
Windows 3.0, a graphical environment, is the third major release of Microsoft Windows, and was released on 22 May 1990. It became the first widely successful version of Windows and a rival to Apple Macintosh and the Commodore Amiga on the GUI front...
was released in May 1990, it was so successful that Microsoft decided to change the primary application programming interface
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
for the still-unreleased NT OS/2 (as it was then known) from an extended OS/2 API to an extended Windows API
Windows API
The Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces available in the Microsoft Windows operating systems. It was formerly called the Win32 API; however, the name "Windows API" more accurately reflects its roots in 16-bit Windows and its support on...
. This decision caused tension between Microsoft and IBM, and the collaboration ultimately fell apart. IBM continued OS/2 development alone, while Microsoft continued work on the newly-renamed Windows NT.
The first public demonstration of Windows NT, at the time called "Windows Advanced Server for LAN Manager", was at a developer conference in August 1991, and the product was formally announced at the Spring 1993 COMDEX
COMDEX
COMDEX was a computer expo held in Las Vegas, Nevada, each November from 1979 to 2003. It was one of the largest computer trade shows in the world, usually second only to the German CeBIT, and by many accounts one of the largest trade shows in any industry sector...
in Atlanta
Atlanta, Georgia
Atlanta is the capital and most populous city in the U.S. state of Georgia. According to the 2010 census, Atlanta's population is 420,003. Atlanta is the cultural and economic center of the Atlanta metropolitan area, which is home to 5,268,860 people and is the ninth largest metropolitan area in...
, Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
.
Application programming interface
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
s in Windows NT are implemented as subsystems atop the undocumented Native API
Native API
The Native API is the publicly- and incompletely-documented application programming interface used internally by the Windows NT family of operating systems produced by Microsoft.. It is predominately used during system boot, when other components of Windows are unavailable. The Program Entry point...
; it was this that allowed the late adoption of the Windows API. Windows NT was the first operating system by Microsoft to use Unicode
Unicode
Unicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems...
internally. Windows NT introduced the Win32 API, a 32-bit implementation of the 16-bit Windows API. Most 16-bit Windows applications could be ported to the new system with minimal changes and a recompile. Win32 also provided native API support for many new features, such as networking and multithreading.
The project had a codename of just "NTOS", which is preserved in the filename of the Windows NT kernel, ntoskrnl.exe.
Since it was targeted to become the next version of OS/2, a more official name of the project was "NT OS/2". This name is preserved up to now in some Windows NT driver development kit files.
System support
NT was designed from the ground up to be portable to other platforms. All kernel and subsystem code was written in CC (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
and C++
C++
C++ is a statically typed, free-form, multi-paradigm, compiled, general-purpose programming language. It is regarded as an intermediate-level language, as it comprises a combination of both high-level and low-level language features. It was developed by Bjarne Stroustrup starting in 1979 at Bell...
. Any differences in core hardware architecture that could not be resolved by a simple recompile (e.g., memory architecture, multi/uniprocessor support) were offloaded to the HAL.
Also, NT's boot architecture borrowed heavily from the ARC
Advanced RISC Computing
Advanced RISC Computing is a specification promulgated by a defunct consortium of computer manufacturers , setting forth a standard MIPS RISC-based computer hardware and firmware environment....
initiative, particularly on non-x86 platforms.
i860
Originally, NT was targeted at the Intel i860Intel i860
The Intel i860 was a RISC microprocessor from Intel, first released in 1989. The i860 was one of Intel's first attempts at an entirely new, high-end instruction set since the failed Intel i432 from the 1980s...
CPU, codenamed N10 (or "N-Ten").
However, the i860 was "horribly behind schedule", so the NT team used an emulator before i860 prototype systems designed in-house (code-named Dazzle) were available. Support for the other platforms followed later and no public release of NT for i860 systems was made. The rationale for targeting the i860 first was to improve portability and avoid producing an x86-centric design.
x86
NT 3.1 supported the Intel x86 32-bit family (80386 and later). Compared to 16-bit Windows 3.x, NT's driver support was somewhat limited. Windows NT 3.1 is the only version of Windows NT that supports multiprocessor 386-based machines.MIPS
Windows NT also supported the MIPS R4000MIPS architecture
MIPS is a reduced instruction set computer instruction set architecture developed by MIPS Technologies . The early MIPS architectures were 32-bit, and later versions were 64-bit...
processor; specifically MIPS systems following the Advanced RISC Computing
Advanced RISC Computing
Advanced RISC Computing is a specification promulgated by a defunct consortium of computer manufacturers , setting forth a standard MIPS RISC-based computer hardware and firmware environment....
(ARC) specification.
Alpha
Early in the NT beta cycle, support was added for the DEC AlphaDEC Alpha
Alpha, originally known as Alpha AXP, is a 64-bit reduced instruction set computer instruction set architecture developed by Digital Equipment Corporation , designed to replace the 32-bit VAX complex instruction set computer ISA and its implementations. Alpha was implemented in microprocessors...
processor. However, because the Alpha itself was delayed, Microsoft's developers did not have access to production Alpha machines to develop on until shortly before NT shipped. Consequently, NT did not initially ship with Alpha support out of the box: the first packages of NT included a mail-in coupon to receive a free CD of NT 3.1 with Alpha support.
16-bit Windows
Windows NT provided a 16-bit compatibility subsystem, called "Windows on WindowsWindows on Windows
In computing, Windows on Windows - commonly referred to by its acronym WOW or WoW - is a software component of 32-bit versions of the Microsoft Windows NT family of operating systems that provides limited support for running legacy Win16 applications - applications written for Windows 3.x...
" (aka WOW), which allowed most Windows 3.x applications to run unmodified on NT. Applications which made direct access to hardware, or depended on DOS-level drivers, were not supported.
In NT 3.1, all 16-bit applications ran within a single WOW process. This meant that a single badly behaving 16-bit application could shut down the WOW session (and any other 16-bit applications running). However, the operating system itself was insulated, so the WOW process could simply be killed and restarted — a significant step forward for Windows' stability.
32-bit Windows
NT also introduced Win32, a 32-bit implementation of the Windows API. This permitted many 16-bit Windows applications to be recompiled for the system with minimal changes. Win32 also allowed the growing body of 16-bit Windows programmers to leverage their skills on the new system. The Win32 API was maintained (with some modifications) with Windows 95Windows 95
Windows 95 is a consumer-oriented graphical user interface-based operating system. It was released on August 24, 1995 by Microsoft, and was a significant progression from the company's previous Windows products...
, further solidifying its role as Microsoft transitioned users off of the 16-bit platform.
Win32 is a comprehensive API, offering OS services ranging from memory management to UI access. NT prevents all user-level applications from directly accessing hardware. This increases system reliability, at the cost of performance. However, this also means that virtually all Win32 applications relied exclusively on the C/C++ Win32 API; the upshot is that porting such an application to another NT-supported system architecture (e.g., moving from x86 NT to MIPS NT) usually required no more than a recompile (some applications might require minor tweaking, such as if assumptions were made in code about endianness
Endianness
In computing, the term endian or endianness refers to the ordering of individually addressable sub-components within the representation of a larger data item as stored in external memory . Each sub-component in the representation has a unique degree of significance, like the place value of digits...
).
OS/2OS/2OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
Though "NT OS/2" was finally released as "Windows NT", it is largely compatible with HPFS disk volumes and the x86 version supports character-modeText user interface
TUI short for: Text User Interface or Textual User Interface , is a retronym that was coined sometime after the invention of graphical user interfaces, to distinguish them from text-based user interfaces...
16-bit OS/2 applications. Many of the OS/2 APIs (particularly NetBIOS/LANMan networking APIs) already existed in almost identical forms in both 16-bit OS/2 and DOS/Windows, so these were incorporated into the Win32 API. For most 16-bit OS/2 programs, minimal code changes were necessary to recompile as NT console
Win32 console
Win32 console is a text user interface implementation within the system of Windows API, which runs console applications. A Win32 console has a screen buffer and an input buffer, and is available both as a window or in text mode screen, with switching back and forth available via Alt-Enter...
applications
Console application
A console application is a computer program designed to be used via a text-only computer interface, such as a text terminal, the command line interface of some operating systems or the text-based interface included with most Graphical User Interface operating systems, such as the Win32 console in...
.
OS/2 and Windows also share the concept of Dynamic-Link Libraries
Dynamic-link library
Dynamic-link library , or DLL, is Microsoft's implementation of the shared library concept in the Microsoft Windows and OS/2 operating systems...
(DLLs). Although the implementation varies somewhat between Windows and OS/2 DLLs, this additional similarity meant that even complex OS/2 applications could usually be converted to NT with little change to the overall design.
POSIX
Windows NT 3.1 included a subsystem that was minimally POSIXPOSIX
POSIX , an acronym for "Portable Operating System Interface", is a family of standards specified by the IEEE for maintaining compatibility between operating systems...
-compatible. This was added largely to help spur sales in US government contracts, as many government agencies mandated POSIX compatibility for consideration.
Note that POSIX compatibility is an API-level requirement. That is, one POSIX operating system won't necessarily be able to execute binary files compiled for a different system, even though both are POSIX compliant. POSIX simply specifies that the source code should compile correctly for each system.
The POSIX subsystem in NT 3.1 primarily provided support for UNIX-style file system permissions and long filename
Long filename
Long filenames , are Microsoft's way of implementing filenames longer than the 8.3 filename, or short-filename, naming scheme used in Microsoft DOS in their modern FAT and NTFS filesystems. Because these filenames can be longer than an 8.3 filename, they can be more descriptive...
s (including permitting filename characters that are otherwise illegal for Windows files, and denying some that are normally legal).
Internet Explorer
Microsoft offered Internet ExplorerInternet Explorer
Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...
starting with IE2
Internet Explorer 2
Microsoft Internet Explorer 2 is a graphical web browser released on November 22, 1995 by Microsoft for Windows 95 and Windows NT and in April 1996 for Apple Macintosh and Windows 3.1....
, and released up to Internet Explorer 5.0
Internet Explorer 5
Microsoft Internet Explorer 5 was a graphical web browser released in March 1999 by Microsoft, primarily for Microsoft Windows, but initially with versions available for Apple Macintosh, Sun Solaris, and HP-UX. It was one of the main participants of the first browser war...
for Windows NT 3.x. Also, a IE 1.5 supported NT, but this patch was actually released after IE2 came out.
Networking
NT 3.1 included support for three network protocols: NBF (using the NetBEUINetBEUI
NetBIOS Frames or NBF protocol is a non-routable network- and transport-level data protocol most commonly used as one of the layers of Microsoft Windows networking in the 1990s. NBF protocol or NetBIOS over IEEE 802.2 LLC is used by a number of network operating systems released in the 1990s, such...
API), TCP/IP, and DLC
Data Link Control
In the OSI networking model, Data Link Control is the service provided by the data link layer. Network interface cards have a DLC address that identifies each card; for instance, Ethernet and other types of cards have a 48-bit MAC address built into the cards' firmware when they are...
.
NetBIOS Frames protocol
At the time of NT's release, NetBIOS Frames protocol (NBF) was the most common protocol on Microsoft LAN ManagerLAN Manager
LAN Manager was a Network Operating System available from multiple vendors and developed by Microsoft in cooperation with 3Com Corporation. It was designed to succeed 3Com's 3+Share network server software which ran atop a heavily modified version of MS-DOS.-Development history:LAN Manager was...
/IBM LAN Server networks. In NT 3.1, it was the only supported protocol for networking with legacy LAN Manager networks, as well as other NT systems. Using NBF, NT could participate in file/print sharing, and NT Advanced Server could act as a Domain Controller
Domain controller
On Windows Server Systems, a domain controller is a server that responds to security authentication requests within the Windows Server domain...
(even sharing DC duties with OS/2 LAN Manager servers).
TCP/IP
Windows NT 3.1 was the first Windows operating system to include TCP/IP support as standard. The TCP/IP stack used was SpiderTCP, developed by Spider SystemsSpider Systems
Spider Systems Ltd. was a computer network products company, based in Edinburgh, Scotland. It was founded in 1983 by several former employees of ICL who had previously worked at ICL's Scottish Development Centre at Dalkeith Palace until its closure earlier that year.Spider Systems produced a wide...
. This was replaced in NT 3.5 with a new stack developed in-house.
The TCP/IP stack included WinSock
Winsock
In computing, the Windows Sockets API , which was later shortened to Winsock, is a technical specification that defines how Windows network software should access network services, especially TCP/IP. It defines a standard interface between a Windows TCP/IP client application and the underlying...
and STREAMS
STREAMS
In computer networking, STREAMS is the native framework in Unix System V for implementing character devices.STREAMS was designed as a modular architecture for implementing full-duplex I/O between kernel or user space processes and device drivers. Its most frequent uses have been in developing...
support, but it was not supported for networking among Microsoft LAN Manager or NT systems. Also, DHCP was not available, so IP addresses had to be manually configured. Support for NBT, DHCP, and WINS was added in NT 3.5.
Data Link Control
Data Link Control (DLC) was supported as a transport protocol for the purpose of communicating with network printers, such as those using an HPHewlett-Packard
Hewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
JetDirect
Jetdirect
JetDirect is the name of a technology sold by Hewlett-Packard that allows computer printers to be directly attached to a Local Area Network. The "JetDirect" designation covers a range of models from the external 1 and 3 port parallel print servers known as the 300x and 500x, to the internal EIO...
interface. It could also be used by Microsoft SNA Server
Host Integration Server
Microsoft Host Integration Server is a gateway application providing connectivity between Microsoft Windows networks and IBM mainframe and AS/400 systems. Support is provided for SNA, 3270 , 5250 , CICS, APPC, and other IBM protocols...
for communication with IBM mainframe
IBM mainframe
IBM mainframes are large computer systems produced by IBM from 1952 to the present. During the 1960s and 1970s, the term mainframe computer was almost synonymous with IBM products due to their marketshare...
systems.
Further reading
- G. Pascal Zachary (1994). "Show Stopper!: The Breakneck Race to Create Windows NT and the Next Generation at Microsoft", Free Press, ISBN 0-02-935671-7
External links
- Guidebook: Windows NT 3.1 Gallery - A website dedicated to preserving and showcasing Graphical User Interfaces