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DIGITAL SNA access server migration guide

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Glossary

The following terms and abbreviations are used in this guide:

Access Name-Shorthand for a set of connection parameters that an access routine uses to access an application on the IBM host. Used by Access Server.

access routines-See OpenVMS access routines

Access Server-Abbreviated product name for DIGITAL SNA Access Server for Windows NT.

Access Server Gateway-The DIGITAL SNA Access Server and the Microsoft SNA Server work together as a gateway between an IBM SNA network on the host side and DIGITAL OpenVMS access routines and other client-side access routines on a DECnet or TCP/IP network. The Access Server Gateway resides on a system running the Windows NT Server operating system.

APPC-See Advanced Program-to-Program Communications

Advanced Program-to-Program Communications (APPC)-Enables networked programs to communicate with one another directly (peer-to-peer), using the LU6.2 protocol in an SNA environment.

base name-Prefix name used to create an Access Server LU name when a session address (old-style LU name) is used in the access routine. The LU name is composed of the base name plus the radix.

Channel Transport (CT)- Channel attached SNA connection. Provides direct parallel connection to a mainframe host. Used when fast connections are required.

CICS-See Customer Information Control System

configuration file-A file containing information required for establishing network communications. Records the last saved configuration settings for a DECnet SNA Gateway or Microsoft SNA Server domain. You can use the parameters in an up-to-date DECnet SNA Gateway configuration file as input to the Access Server and SNA Server configuration files.

An Access Server configuration file contains Access Names, Name Mapping, and Authorization Records. Access Server Configurations appear as components of the DECSNAAdapterServices subtree in the Windows NT Registry. An SNA configuration file contains definitions for servers, connections, LUs, and other SNA Server entities. The default SNA Server configuration file is COM.CFG.

CT-See Channel Transport

Customer Information Control System (CICS)- IBM application subsystem that resides on an IBM host and provides a high-level programming interface for terminal-oriented application programs. It enables IBM components in an IBM SNA environment to interact with the DIGITAL SNA Access Server by defining the characteristics of the remote system to the IBM host. CICS controls sessions between application programs and the devices connected to those programs.

DECnet-DIGITAL's network transport protocol that can provide communication among many different operating systems. An Access Server Gateway can be implemented across a DECnet network.

DECnet SNA Gateway-Either the DECnet SNA Gateway-CT, DECnet SNA Gateway-ST, or both. A distinction between hardware and software is made only when it is relevant to the discussion in the text.

FEP-See Front End Processor

front end processor (FEP)-PU type 4

gateway-A hardware and software solution that serves as a shared entry point between a DECnet or TCP/IP network and an IBM SNA network. A gateway is a communication bridge between programs that have different network, hardware, and software protocols.

IBM host-An IBM mainframe system that connects a network of PCs over a DECnet or TCP/IP connection. The host typically manages much of the interaction and shares its applications with client PCs via the SNA Server.

logical unit (LU)-Configurable. Specifies the type of session and contains required configuration information that enables a connection to be established. LUs supported by the Access Server include LU0, LU1 (printer), LU2 (terminal), and LU3 (printer).

Logical Unit Application (LUA)-Conventional logical unit application programming interface (API). Enables communication between a PC and a host. Provides direct access to LU0, LU1, LU2, and LU3 datastreams. The Access Server is designed to use LUA type LUs.

LU-See Logical unit

LU list-A list of LU or LU pool names in the Access Server Manager.

LU name-Identifies an LU in an SNA network.

LU pool-A group of LUs of the same type. Enables maximum access to the LUs in the pool by providing a choice of LUs on different connections. A user using the pool can get LU access as long as one of the pooled LUs is available. Can also be used to provide hot backup for a network. An LU pool name is referenced just like an LU name.

LUA-See Logical unit application

old-style name or old-style LU name-An LU name established on an existing DECnet SNA Gateway-ST or DECnet SNA Gateway-CT. The format of an old-style name is PU.session (for example, SNA-0.55, where SNA-0 is the PU name and 55 is the session address within the PU). Old-style LU names may be reused with a simple remapping to new LU names in an Access Server Gateway.

OpenVMS access routines-In this guide, OpenVMS SNA applications (see next entry) are referred to collectively as access routines.

OpenVMS SNA applications-SNA applications that run on DIGITAL OpenVMS systems and emulate specific IBM functionality, including 3270 terminal emulation (LU2), 3287 printer emulation (LU1 and LU3), RJE emulation, 3270 data stream programming interfaces, and LU0 programming interfaces.

physical unit (PU)-Network-addressable entity consisting of software, hardware, and microcode used to manage a variety of devices, including IBM host mainframe (PU5), Front End Processor (PU4), SNA Server (PU2 or PU2.1).

PU-See Physical unit

radix-Hexadecimal or decimal session address to append to the base name to create an Access Server LU name. Used when a session address (old-style LU name) is used in the access routine. The LU name is composed of the base name plus the radix.

Remote Job Entry (RJE)-DIGITAL SNA Remote Job Entry for OpenVMS is a layered software product that provides batch job processing between an OpenVMS system and an IBM host within a DECnet or TCP/IP network. Using RJE, the OpenVMS system user can submit batch job files to the IBM remote host (mainframe) and receive job output, transfer data that can be used for periodic update of databases and other applications on the mainframe, and perform general file transfer between the IBM host and the local workstation.

RJE-See Remote Job Entry

SDLC-See Synchronous Data Link Control

SNA-See Systems Network Architecture

SNA Server-Abbreviated product name for Microsoft SNA Server for Windows NT. Together with the DIGITAL SNA Access Server, enables OpenVMS access routines to communicate with an IBM host system.

ST-See Synchronous Transport

Synchronous Data Link Control (SDLC)-Standard serial phone line connection from SNA server to host. Communicates with the host through a Front End Processor.

Synchronous Transport (ST)-Connection through serial front end processor to a mainframe host. Used when synchronous, lower-speed connections are desirable.

Systems Network Architecture (SNA)-IBM's proprietary computer networking architecture that has become a de facto standard for communication protocols and message formats. Originally a hierarchical architecture, enabling efficient communication between unintelligent terminals and intelligent host. Now adapted into providing distributed, peer-oriented communications and computing among intelligent desktops. Microsoft SNA Server and DIGITAL SNA Access Server enable distributed desktop computers to access IBM SNA networks and computers.

TCP/IP-Transmission Control Protocol/Internet Protocol. Wide area network (WAN) transport protocol that can provide communication among many different operating systems. An Access Server Gateway can be implemented across a
TCP/IP network.