
 






          Software
          Product
          Description

          ________________________________________________________________

          PRODUCT NAME:  VAX Packetnet System Interface     SPD 27.78.02
                         Access, Version  4.3

          DESCRIPTION

          The VAX Packetnet System Interface Access (VAX P.S.I. Access)
          product allows a suitably configured DECnet-VAX system in a DEC-
          net environment to make logical connections to Packet Switching
          Data Networks (PSDNs) by using one or more connector node(s).
          VAX P.S.I. Access, with the connector node providing physical
          connection(s) to a PSDN(s), enables process-to-process and ter-
          minal communications between the Access system and the remote
          Data Terminal Equipment (DTE).

          The connector node may be any of the following:

          o  An X25router 2000 product (refer to X25router 2000 Software
             Product Description SPD 28.86.xx ).

          o  VAX P.S.I.  configured in Multi-host mode (refer to VAX 
             Packetnet System Interface P.S.I. Software Product Description
             SPD 25.40.xx).

          DECnet logical links are established by VMS to connect the VAX
          P.S.I. Access node to the connector node. These links may use
          any supported DECnet communications path between the VAX P.S.I.
          Access node and the connector node, provided they themselves do
          not use an X.25 connection. VAX P.S.I. Access uses these links
          to transmit X.25 or X.29 messages between the connector node and
          the VAX P.S.I. Access host.



                                       DIGITAL                   July 1990

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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          Note that successful use of an X.29 connection, either for in-
          coming X.29 calls or by means of the host-based PAD utility
          supplied with VAX P.S.I. Access, depends on the DECnet circuit
          between the Access and connector nodes having a low response
          time. This requires high-speed DECnet connections and few inter-
          mediate routing nodes.

          A single VAX P.S.I. Access host can connect to one or more
          connector nodes concurrently, and hence access all PSDN(s)
          accessible from those connector nodes. When VAX P.S.I. Access is
          installed, one of these connector nodes/PSDN combinations must
          be established as the default gateway for outbound and inbound
          traffic.

          Features

          VAX P.S.I. Access is a VMS layered product and can be used in
          the following ways:

          o  Process-to-process (X.25) communication

          o  Process-to-terminal (X.29) communication

          o  Terminal-to-Process (X.29) communication

          o  Open System Interconnection

          Process-to-process (X.25) Communication

          VAX P.S.I. Access supports access for VMS user programs written
          in VAX MACRO and native mode high-level languages such as VAX
          FORTRAN. Programs executing in PDP-11 compatibility mode cannot
          use VAX P.S.I. Access.

          The VAX P.S.I. Access programming interface allows application
          programs to access the service interface to the packet level via
          the standard VMS QIO interface. Functions include the setting
          up and breaking of network connections, data transmission and
          reception, sending and receiving of interrupt messages, and re-
          setting of virtual circuits. The interface also allows splitting

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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          and recombining of messages which are longer than the packet
          size selected for the circuit.

          The programming interface enables an application program using
          VMS System Services to communicate with complementary software
          on other systems (Digital or non-Digital DTEs) accessible via
          the X.25 connection.

          Process-to-terminal and Terminal-to-process (X.29) Communica-
          tion

          VAX P.S.I. Access supports terminal communications according to
          CCITT recommendations X.3, X.28, and X.29 for:

          o  Outgoing terminal traffic

             VAX P.S.I. Access host users may make outgoing calls to
             other Digital or non-Digital CPUs, or suitable network PADs
             accessible via a PSDN, using the X.29 programming interface
             or by using the host-based Packet Assembly/Disassembly (PAD)
             supplied with VAX P.S.I. Access. The PAD facility accepts
             DCL-style commands or CCITT X.28 commands.

          o  Incoming terminal traffic

             The X.29 Interactive Terminal Interface allows remote asyn-
             chronous terminals (character-mode DTEs) connected to the
             network to communicate with the VAX P.S.I. Access host in a
             manner similar to local terminals. Dissimilarities may appear
             as a result of delays caused by the PSDN(s) and the various
             PAD parameter settings chosen by the user or peculiar to the
             PSDN(s). In this case, the remote PAD must perform code con-
             versions between ASCII and the code the terminal uses. Note
             that there may be some restrictions imposed by the PSDN(s).

          Terminal parameters defined in the X.3 recommendation are ex-
          plicitly supported. Network-specific enhancements or extensions
          to the X.3 parameters are available at both the X.29 programming
          interface and the host-based PAD user interface. Terminal pro-
          cesses that depend on these extensions may cause problems when

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          used on other PSDNs or when accessing one PSDN via another (for
          example, international access).

          The X.29 terminal interface is compatible with the local termi-
          nal interface, except for those facilities where the PSDN does
          not provide adequate support. The X.29 interface includes sup-
          port for specific X.29 signaling. For example, the break key
          can be used to disable output, and the interrupt message can be
          mapped directly to the VMS interrupt character.

          The host-based PAD employs a DCL-style command syntax offering
          the ability to reference the CCITT PAD parameters symbolically,
          as well as an interface that conforms to the standard CCITT
          command signals. The host-based PAD also offers the capability
          of running multiple X.29 sessions using the VMS SPAWN and ATTACH
          commands. The host-based PAD supports reception of reselection
          messages to allow X.29 calls to be redirected to another DTE.

          The X.29 programming interface is similar to the X.25 interface
          and allows a VMS process to control the virtual circuit (for
          example, to modify PAD parameters or clear a call). The X.29
          programming interface can also be used to make an outgoing call
          to a remote PAD. The programming interface allows generation of
          PAD reselection messages.

          The maximum number of terminals supported (both local and remote
          X.29) must not exceed the number supported by VMS. The use
          of PVCs for X.29 connections is not defined by the 1980 and
          1984 CCITT recommendations and is not available with VAX P.S.I.
          Access.

          Open System Interconnection

          VAX P.S.I. Access may be used for Open System Interconnection
          (OSI) communication using the OSI Applications Kernel prod-
          uct (OSAK). Refer to the VAX OSI Applications Kernel Software
          Product Description (SPD 27.47.xx).


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          VAX P.S.I. Access may also be used with VAX FTAM for managing
          files on open systems (refer to VAX FTAM Software Product
          Description SPD 29.86.xx), and with the VAX Message Router
          X.400 Gateway to enable message exchange with other X.400 sys-
          tems in X.400 public or private networks. Refer to the VAX Mes-
          sage Router X.400 Gateway Software Product Description (SPD
          27.50.xx).

          VAX P.S.I. Access also provides features of X.25 which permit a
          Connection Oriented Network Service (CONS) over X.25, according
          to ISO 8348.

          Virtual Circuits

          VAX P.S.I. Access supports both Permanent Virtual Circuits
          (PVCs) and Switched Virtual Circuits (SVCs) from the connector
          node, and supports up to 512 virtual circuits in total per host
          machine. One virtual circuit is used for each:

          o  Incoming or outgoing X.29 terminal connection

          o  X.25 call, using either an SVC or PVC

          VAX P.S.I. and VAX P.S.I. Access Running on the Same System

          In a network consisting of more than one connector node in-
          volving one or more VAX P.S.I. Multi-host nodes, users on a
          Multi-host node may need to gain access to PSDN(s) connected to
          another connector node. This is accomplished by installing both
          VAX P.S.I. and VAX P.S.I. Access on the same node in combination
          mode.

          Configuration

          VAX P.S.I. Access provides a configuration procedure to con-
          figure a VAX P.S.I. Access system locally. This allows network
          managers to create a configuration after initial installation,
          or subsequently when reconfiguration is necessary.



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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          Network Management

          VMS provides a Network Control Program (NCP) for management
          of both DECnet-VAX and VAX P.S.I. This program allows network
          managers to define the line(s) and PSDN(s) to which the system
          is connected, select the mode (DTE or DCE) of each, specify
          destinations for incoming calls, access counters, and perform
          other maintenance functions.

          Problem Solving

          The TRACE utility assists problem solving by tracing and analyz-
          ing information at various stages as it passes between the PSDN,
          the connector node and the VAX P.S.I. Access node. Event logging
          is available by means of normal VMS mechanisms.

          P.S.I. Accounting

          The P.S.I. Accounting utility enables the system manager to
          obtain information on VAX P.S.I. Access and network usage. The
          P.S.I. Accounting utility can extract the information collected
          and display the information directly on a terminal or write the
          information to a file. Information can be extracted for selected
          records or a summary produced. The P.S.I. Accounting utility is
          compatible with the VMS Accounting utility.

          In the case of incoming X.29 calls, no information can be stored
          relating to the process/account on which a user is logged; this
          can be obtained through correlation with VMS accounting records.

          On a VAX P.S.I. Access node, the P.S.I. Accounting utility
          records details of calls to and from the Access node only. Refer
          to the appropriate SPD for the connector node for  details of
          the accounting features available.

          If the connector node is a VAX P.S.I. Multi-host node, P.S.I.
          Accounting should also be used at the Multi-host node to gather
          comprehensive accounting data. Refer to the VAX P.S.I. SPD
          (25.40.xx) for more information about the available accounting
          features.

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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          P.S.I. Security

          The P.S.I. Security utility allows control of both remote DTE
          access to VAX P.S.I. Access, and access to the PSDN(s) by VMS
          processes. The Security utility allows for access control on the
          basis of:

          o  The remote DTE numbers involved, either on the basis of
             individual DTE numbers or groups of DTE numbers with common
             leading digits

          o  The process making the outgoing call or the application
             handling the incoming call

          o  Whether or not the call is normally or reverse charged

          On a VAX P.S.I. Access node, the P.S.I. Security utility per-
          forms security checks for calls to and from the Access node
          only. Refer to the appropriate SPD for the connector node for
          details of the security features available.

          If the connector node is a VAX P.S.I. Multi-host node, P.S.I.
          Security should also be used at the Multi-host node to provide
          comprehensive security. P.S.I. Security on a VAX P.S.I. Multi-
          host node checks both incoming and outgoing calls for the right
          to communicate with the VAX P.S.I. Access node. Refer to the
          VAX P.S.I. Software Product Description (SPD 25.40.xx) for more
          information about the available security features.

          P.S.I. Mail

          The P.S.I. Mail utility allows communication across a PSDN via
          electronic mail between two VMS systems running VAX P.S.I. or 
          VAX P.S.I. Access, using the VMS Mail facility even in the absence
          of any DECnet communications between the two DTEs. Refer to the 
          VMS Operating System Software Product Description (SPD 25.01.xx)
          for more  information about VMS Mail.

          Conformance to Standards

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          Please refer to appropriate SPD for the connector node for
          details of the standards and protocol options supported.

          PREREQUISITE SUPPORT

          The customer and Digital must jointly prepare a Network Profile
          and Customer Support Plan covering all the intended network
          nodes, their usage of SVCs, PVCs and other network facilities,
          and their support. Without this Network Profile and Customer
          Support Plan, Digital cannot support the network connections.

          Support services for VAX P.S.I. Access require that a corre-
          sponding or a greater level of service are obtained for the
          connector node(s) used.

          INSTALLATION

          Digital requires that a customer's first purchase of this soft-
          ware product include Digital Installation Services. These ser-
          vices provide for installation of the software product by an
          experienced Digital Software Specialist.

          Only customers experienced with Digital's X.25 products should
          attempt second or subsequent installations. Digital recommends
          that all other customers purchase Digital's Installation Ser-
          vices.

          Customer Responsibilities

          Before installation of the software, the customer must:

          o  Previously have installed all required software and hardware,
             including terminals.

          o  Obtain, install and demonstrate that both the connection from
             the connector node to the PSDN and the DECnet connection to
             the connector node are operational.

          o  Check the requirements for the connector node installation
             from the appropriate connector node SPD.

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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          o  Make available for a reasonable period of time, as mutually
             agreed by Digital and the customer, all hardware, communi-
             cation facilities and terminals that are to be used during
             installation.

          Delays caused by any failure to meet the responsibilities will
          be charged, at the then prevailing rate, for time and materials.

          Courtesy Installation Service

          This software product will be installed by Digital at no addi-
          tional charge if purchased concurrently with a Startup Service
          Package that includes installation service. Both the operating
          system and this product must be installed concurrently. This
          service may not be available in all countries.

          HARDWARE REQUIREMENTS

          VAX, MicroVAX, VAXstation, or VAXserver configuration as speci-
          fied in the System Support Addendum (SSA 27.78.02-x).

          SOFTWARE REQUIREMENTS *

             VMS Operating System

             DECnet-VAX (either end-node or full-function)

          *  Refer to the System Support Addendum (SSA 27.78.02-x) for
             availability and required versions of prerequisite software.

          ORDERING INFORMATION

          Software Licenses: QL-061A*-**
          Software Media: QA-061A*-**
          Software Documentation: QA-061AA-GZ
          Software Product Services: QT-061A*-**

          *  Denotes variant fields. For additional information on avail-
             able licenses, services and media, refer to the appropriate
             price book.

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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          SOFTWARE LICENSING

          This software is furnished under the licensing provisions of
          Digital's Standard Terms and Conditions. For more information
          about Digital's licensing terms and policies, please contact
          your local Digital office.



          LICENSE MANAGEMENT FACILITY

          This layered product support the License Management Facility.
          License units for this product are allocated on a CPU-capacity
          basis.

          For more information on the License Management Facility, refer
          to the VMS Operating System Software Product Description (SPD
          25.01.xx) or the VMS documentation set.

          For more information about Digital's licensing terms and poli-
          cies, contact your local Digital office.

          SOFTWARE PRODUCT SERVICES

          A variety of service options are available. For more informa-
          tion, please contact your local Digital office.

          SOFTWARE WARRANTY

          Warranty for this software product is provided by Digital with
          the purchase of a license for the product as defined in the
          Software Warranty Addendum of this SPD.

          Use of the VAX P.S.I. Access software in conjunction with a
          connector node for which Digital support has not been purchased
          and/or is not available invalidates any warranty or support
          offered in this SPD.


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          VAX Packetnet System Interface Access, Version 4.3  SPD 27.78.02



          Use of the VAX P.S.I. Access software and a connector node with
          a PSDN which Digital has not tested invalidates any warranty or
          support offered in this SPD. This software warranty applies only
          to those PSDN(s) which are fully supported by the connector node
          software.


          [R]  The DIGITAL Logo is a registered trademark of Digital
               Equipment Corporation.

          [TM] DECnet, MicroVAX, VAX, VAXserver, and VAXstation are trade-
               marks of Digital Equipment Corporation.



























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