dtj v04-01 1992

This issue of the Digital Technical Journal (Winter 1992) is primarily dedicated to PATHWORKS: PC Integration Software by Digital Equipment Corporation.

The document highlights PATHWORKS as a family of software products designed to integrate diverse Personal Computer (PC) client platforms (MS-DOS, Microsoft Windows, OS/2, Apple Macintosh) with larger server systems (VMS and ULTRIX) into enterprise-wide network environments. The core objective is to provide PC users with transparent access to network resources such as remote files, printers, databases, electronic mail, and X Window System applications over various physical networks and protocols.

Key areas covered in the journal include:

• An Overview of the PATHWORKS Product Family: Detailing its evolution, supported hardware (Intel, Motorola 68000), operating systems, and a wide array of transport and service protocols (DECnet, TCP/IP, NetBIOS, AppleTalk, IPX/SPX, SMB, NCP, AFP, PAP, NFS).
• PATHWORKS for VMS File Server: Discussing its architecture (single, multithreaded process), file system mapping between DOS/OS/2 and VMS, performance optimization through data caching and an optimized transport interface, and security mechanisms.
• Design of the PATHWORKS for ULTRIX File Server: Explaining its multiple process model, interprocess communication, file name and attribute mapping, printing support, and performance considerations.
• Optimized PATHWORKS Transport Interface: Detailing the engineering efforts to improve server performance, particularly for small data transfers, by optimizing the transport layer and data buffering.
• Microsoft Windows Network Virtual Device Drivers in PATHWORKS for DOS: Describing the development of virtual device drivers (VDDs) to manage DECnet and NetBIOS operations within the Windows enhanced mode environment, enabling support for peripheral devices and memory resources.
• excursion for Windows: Integrating Two Windowing Systems: Showcasing an application that seamlessly integrates X Window System and Microsoft Windows environments on a single PC screen, allowing for shared display and data exchange.
• Capacity Modeling of PATHWORKS Client-Server Workloads: Presenting a queuing analytical model used to understand server resource consumption, predict performance, and identify bottlenecks in client-server environments.

In essence, the journal showcases Digital's efforts in building open, heterogeneous computing environments that enable seamless integration and efficient resource sharing between PCs and larger systems across local and wide area networks.