Software Product Description ___________________________________________________________________ PRODUCT NAME: DEC Distributed Server Library for OpenVMS, Version 1.0 SPD 39.64.00 DESCRIPTION The DEC Distributed Server Library (DSL) is a set of tools to build client applications and application-specific servers in heterogeneous operating environments. DSL functions within a client/server archi- tecture. The DSL has the following components: o DEC Distributed Server Library Server for OpenVMS[*] o DEC Distributed Server Library Client for OpenVMS o DEC Distributed Server Library Client for Windows[TM] Features DSL features are described according to the following: o DSL Client/Server Architecture o Tools to Build Clients and Servers o Development Environment o Documentation o Sample Application ____________________ The terms OpenVMS and VMS refer to the OpenVMS Operating System. DIGITAL September 1992 AE-PSHPA-TE DSL Client/Server Architecture Applications use the DEC Distributed Server Library within a client /server architecture. Client processes (on separate, remote machines) send requests to a server process. The server process performs each request and may send back a reply to the client. DSL supports a large number of simultaneous client processes, limited only by the number of logical connections allowed by DECnet. Further- more, all communications are asynchronous, so each client process can issue concurrent requests to many remote servers. There is one server to handle incoming client requests that has a built- in multiplexer for managing a set of subprocesses. Each subprocess is a request handler. When a new request arrives, the server passes the request to one of the request handlers, which may send a reply to the client. The number of handler subprocesses is variable and can be tuned to maximize server performance. Tools to Build Clients and Servers DSL provides the following: o A network communications interface for clients to exchange requests and replies with a server o A multiplexer to optimize server transaction rates o Libraries for: - Writing a client application that uses synchronous or asynchronous routines to establish and terminate connections, send requests, and process replies - Writing a single process or multiprocess server o Database independence DSL applications can use any database or programming language that conforms to the VAX or the MIT C[TM] calling standard 2 Development Environment DSL provides an application programming interface (API) and support libraries. The interface allows programmers to write DSL client and server programs without requiring knowledge of network communications. Supports Use of Native Windowing Systems: DSL is compatible with DECwindows and Motif(R) on OpenVMS and Microsoft(R) Windows on MS-DOS(R). 3 Nonblocking Execution: DSL clients support nonblocking programs. In event-driven processing environments, such as Microsoft Windows, programs may be structured to include an event-dispatching mechanism and a collection of proce- dures. These procedures are invoked by the dispatching mechanism when an event occurs. DSL client services allow an application to release control to the event- dispatching mechanism without waiting for a response from the DSL server. This is particularly important in cases where network delays exist or a large amount of processing is being performed by the DSL server. Windows, Memory Models, and Modes: DSL requires Microsoft Windows running in enhanced mode. DSL supports small, medium, large, and huge memory models. Documentation The DSL documentation set includes the following manuals: o Programmer's Reference Manual This manual describes how to develop and test client programs that use DSL servers. It includes detailed information on DSL components and functions, design and development guidelines, system manage- ment and interface reference information. o Installation Guide for OpenVMS This guide describes how to install the DSL Client and the DSL Server process on OpenVMS, and explains how to run the Installation Ver- ification Procedure (IVP). o Installation Guide for Windows This guide describes how to install the DSL Client software on a PC-based system running MS-DOS. Release Notes are available on-line as part of the media package. The Release Notes contain information specific to each release of DSL and information added after the production date for the DEC Distributed Server Library's documentation set. 4 Sample Application A complete sample application is provided, including client programs and DSL server code. The sample application includes all necessary prod- uct executable images as well as source code modules. Inclusion of the source code allows the customer to use the sample program as a tem- plate for developing custom client programs. INSTALLATION Only experienced customers should attempt installation of this prod- uct. Digital recommends that all customers purchase Digital's Instal- lation Service. This service provides for installation of the soft- ware by an experienced Digital software specialist. HARDWARE REQUIREMENTS DSL requires the following hardware for its components: o DSL Client for OpenVMS and DSL Server for OpenVMS: The DSL Client and Server software for OpenVMS runs on the follow- ing VAX processors: VAX 3xxx, VAX 4xxx, VAX 6xxx, VAX 7xxx, VAX 8xxx, and VAX 9xxx. Refer to the complete list of supported processor and /or hardware configurations as specified in the System Support Ad- dendum (SSA 39.64.00-x). o DSL Client for Windows: The DSL Client for Windows will run on one hundred percent IBM[TM]- compatible Intel[TM] PC systems as specified in the System Support Addendum (SSA 39.64.00-x). 5 SOFTWARE REQUIREMENTS DSL requires the following software for its three components: o DSL Client for Windows: - MS-DOS Operating System - Microsoft Windows - Microsoft C[TM] - PATHWORKS for DOS (see SPD 55.007.xx) o DSL Client for OpenVMS and DSL Server for OpenVMS: - OpenVMS Operating System (see SPD 25.01.xx), including DECnet-VAX - Any language compiler that supports either the VAX calling stan- dard (VAX Ada, VAX BASIC, VAX BLISS, VAX C, VAX COBOL, VAX FORTRAN, VAX MACRO-32, VAX Pascal, VAX PL/1) or the MIT C calling stan- dard 6 ORDERING INFORMATION The following table contains all the ordering information for the DEC Distributed Server Library. 7 ___________________________________________________________________ Licenses, Kits, and Services___________________Order_Number____________________________ Software_Licenses: DEC Distributed Server QL-MV7**-** Library Server for Open- VMS: DEC Distributed Server QL-MV8**-** Library Client for Open- VMS: DEC Distributed Server QL-MV9**-** Library Client for Win- dows: Software_Media_Kits: DEC Distributed Server QA-MV7**-** Library Server for Open- VMS (TK50): DEC Distributed Server QA-MV8**-** Library Client for Open- VMS (TK50): DEC Distributed Server QA-MV9**-** Library Client for Win- dows (RX23 diskette): DEC Distributed Server QA-MV9**-** Library Client for Win- dows (RX33 diskette): Software_Documentation_Kit:_QA-MV7**-** Software_Product_Services: QT-MV***-** * Denotes variant fields. For additional information on available licenses, services, and media, refer to the appropriate price book.______________________________________________________________ 8 SOFTWARE LICENSING Each DSL Client license grants the user rights to make a single con- nection from any client to a server. The client license is installed on the server machine. To provide concurrent service to multiple clients, more than one client license may be installed. The DSL Server license grants the user rights to run any number of servers on a host machine. This software is furnished under the licensing provisions of Digital Equipment Corporation's Standard Terms and Conditions. For more in- formation about Digital's licensing terms and policies, contact your local Digital office. License Management Facility Support This layered product supports the OpenVMS License Management Facil- ity. License units for this product are allocated on an Unlimited System Use and Concurrent Use basis. Each Concurrent Use license allows any one individual at a time to use the layered product. For more information on the License Management Facility, refer to the OpenVMS Operating System Software Product Description (SPD 25.01.xx) or the License Management Facility manual of the OpenVMS Operating Sys- tem documentation set. SOFTWARE PRODUCT SERVICES A variety of service options are available from Digital Equipment Cor- poration. For more information, contact your local Digital office. 9 SOFTWARE WARRANTY Warranty for this software product is provided by Digital Equipment Corporation with the purchase of a license for the product as defined in the System Support Addendum for this SPD. (R) IBM is a registered trademark of International Business Ma- chines Corporation. (R) Microsoft and MS-DOS are registered trademarks of Microsoft Corporation. (R) Motif is a registered trademark of the Open Software Founda- tion, Inc. [TM]Intel is a trademark of Intel Corporation. [TM]Microsoft C and Windows are trademarks of Microsoft Corpora- tion. [TM]MIT C is a trademark of the Massachusetts Institute of Technol- ogy. [TM]The DIGITAL Logo, DEC, DEC Distributed Server Library, DECnet, DECwindows, Digital, MicroVAX, OpenVMS, PATHWORKS, TK, VAX, VAX Ada, VAX BASIC, VAX C, VAXcluster, VAX COBOL, VAX FORTRAN, VAX Pascal, VAXserver, VAXstation, and VMS are trademarks of Digital Equipment Corporation. 10