PRODUCT NAME: DECnet/SNA VMS 3270 Data Stream                  SPD 26.87.05
              Programming Interface, Version 1.4  

DESCRIPTION

The DECnet/SNA VMS 3270 Data Stream Programming Interface (3270 DS) is a 
layered software product that allows user-written applications running on 
suitably configured VMS systems within a DECnet network or on suitable VMS 
systems within a VMS/SNA environment to exchange messages with cooperating 
applications in an IBM host. The 3270 DS software exists in the VMS system as a 
shareable image.  Access between the cooperating DIGITAL and IBMROF
ROIBM is a registered trademark of International Business Machines, Inc.
F applications 
is via the DECnet/SNA Gateway or via VMS/SNA software. 

The 3270 DS programming interface is a collection of subroutines designed to 
provide an easy-to-use interface for the DECnet/SNA Gateway (or VMS/SNA) 
application programmer who has a specific need to interface to an IBM 
application subsystem which uses LU Type 2 (LU2) protocol. The product can be 
used with many types of applications. As an example, a customized 3270 terminal 
emulator application can be written by a user and layered on top of 3270 DS. 
Applications can be event driven or synchronous in nature with no loss in 
available functions. 

Features

The 3270 DS product is designed to insulate the VMS application programmer from 
the inner workings of the SNA network environment as much as possible, thus 
allowing the user to concentrate on solving the application problem. The 
product performs the following SNA functions on the user's behalf: 

oo Receives and interprets the bind

oo Accepts the bind and starts the session

oo Maintains the state machines for chaining, bracketing, and data flow   
  control 

oo Processes an Unbind Type 2 automatically

As a result, the VMS user is required to perform a minimum of SNA functions 
including processing the CLEAR and CANCEL functions and handling contention. 

This product is a set of subroutines used to perform such functions as 
establishing sessions, sending data, receiving data, and disconnecting 
sessions. In addition, the 3270 DS interface may be used to interpret the 3270 
data stream and build a screen image. The VMS application is then free to 
interact with the screen image. 

The 3270 DS product allows two modes of connection: Data Stream Mode and Field 
Mode. 

Data Stream Mode 

Data Stream Mode provides a means to send and receive uninterpreted 3270 data 
streams as defined by IBM. In this mode, all SNA specific functions are 
performed by the interface. For example, the VMS application is not required to 
handle chaining, brackets, RUs, or RHs. At the same time, this mode allows the 
interface to provide the VMS application with the complete 3270 data stream. It 
is the VMS user's responsibility to interpret the outbound data stream for 3270 
orders and commands, and to build and manipulate a screen image (if desired). 
Similarly, it is the VMS user's responsibility to build the inbound data stream 
from his own screen image or from some other data structure. 

A VMS application which needs to use extended attributes must use a Data Stream 
Mode connection. Extended attributes are extensions to the basic field 
attributes, namely: 

oo Extended highlighting (blink, reverse video, underscore)

oo Color

oo Programmed symbols (selectable symbol set)

oo Screen partitions and windows

Field Mode

Field Mode performs a presentation service to provide a screen image interface. 
The screen image may be read field by field, or accessed directly. The 
interface interprets 3270 commands and orders in an outbound data stream to 
build the screen. In addition, it produces an inbound 3270 data stream from the 
updated screen image. 

As with the Data Stream Mode, Field Mode insulates the VMS user from the SNA 
protocol. Extended attributes are not supported by the Field Mode connection. 

Asynchronous Event Notification 

The 3270 DS product provides a mechanism for a VMS user application to receive 
control when an asynchronous ``network event'' occurs such as disconnection of 
a DECnet logical link, an SNA circuit failure, or the receipt of an Unbind Type 
2 from IBM. The VMS application is called at a notification entry point defined 
by the application at connection time; an indication of the event that occurred 
is reported. 

User Interface 

Users of the DECnet/SNA VMS 3270 DS product should be experienced VMS 
application programmers. They can use any of the VMS programming languages 
which conform to the VMS Calling Standard to create application programs which 
interact with application programs on an IBM system. The user documentation 
provides example segments written in the following languages: 

oo MACRO-32

oo VAX BLISS-32 Implementation Language

oo VAX C

oo VAX COBOL

oo VAX FORTRAN

oo VAX PASCAL

oo VAX PL/I

The users of the 3270 DS product are not required to have extensive knowledge 
of SNA. 

Features of Version 1.4

oo VMS 3270 DS V1.4 supports Digital's License Management Facility.

oo VMS 3270 DS V1.4 allows, on supported DECnet/SNA gateways and VMS/SNA 
  systems, secured Logical Unit (LU) access via the SNA3270$REQUEST_CONNECT 
  procedure call.

INSTALLATION

Only experienced customers should attempt installation of this product. DIGITAL 
recommends that all other customers purchase DIGITAL's Installation Services.  
These services provide for installation of the software product by an 
experienced DIGITAL Software Specialist. 

Customer Responsibilities

Before DIGITAL installation of the software the customer must:
     
oo Have previously installed all requisite hardware including terminals and 
  DECnet/SNA gateway products.

oo Obtain, install, and demonstrate as operational any modems and other 
  equipment and facilities necessary to interface to DIGITAL's communications 
  equipment.   

oo Have generated, to DIGITAL's satisfaction, any necessary IBM host software 
  that will be communicating with the DECnet/SNA gateway or VMS/SNA and the 
  3270 DS Programming Interface.

oo Make available for a reasonable period of time, as mutually agreed by DIGITAL 
  and the customer, all hardware, communications facilities, and terminals that 
  are to be used during installation.

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

Successful use of this product requires that:

oo The customer must be prepared to work with both DIGITAL and IBM systems 
  personnel to coordinate the pre-installation activities.

oo The customer should be capable of modifying IBM component generation 
  parameters to support either the DECnet/SNA gateway or VMS/SNA and the 3270 
  DS Programming Interface.


WARRANTY LIMITATIONS
         
IBM Supported Configurations
         
This software has been tested and is warranted against IBM System/370 (includes 
30xx and 43xx series) class processor systems configured with the following IBM 
software.  While this software may function correctly with other IBM software 
and equipment, and with software other than that supported by IBM, DIGITAL 
cannot offer its standard warranty for this software unless it has been tested 
with such equipment and software configurations. 
       
The following list shows the configurations with which the software has been 
tested and is warranted: 

+-----------------------------------------------------------------------+
| Software Product				 |  Version  | Release  |
+-----------------------------------------------------------------------+
|IBM MVS Environment				 	     		|
|						 	     		|
+-----------------------------------------------------------------------+
|MVS/SP						 |     1     |  3.6	|
|						 |     	     |  3.7 	|
|						 |     2     |  1.3	|
|						 |	     |  1.5 	|
|						 |	     |  1.7 	|
|						 |	     |  2.0	|
+-----------------------------------------------------------------------+
|TSO/E/XA					 |	     |  3.0	|
|						 |	     |  4.0	|
+-----------------------------------------------------------------------+
|ISPF/MVS					 |     2     |  2.0	|
|						 |	     |  3.0	|
+-----------------------------------------------------------------------+
|ISPF/PDF					 |     2     |  2.0	|
|						 |	     |  3.0	|
+-----------------------------------------------------------------------+
|IMS						 |     2     |  1.0 	|
|						 |	     |  3.0	|
+-----------------------------------------------------------------------+
|CICS/OS/MVS					 |     1     |  6.1 	|
|						 |	     |  7.0	|
+-----------------------------------------------------------------------+
|NCCF						 |     2     |  2.0     |
+-----------------------------------------------------------------------+
|NETVIEW					 |     1     |  1.0	|
|						 |	     |  2.0	|
+-----------------------------------------------------------------------+
|IBM VM Environment				 	       		|
+-----------------------------------------------------------------------+
|VM/SP						 |     1     |  4.1     |
|						 |	     |  5.0	|
+-----------------------------------------------------------------------+
|CMS						 |     	     |  4.1	|
|						 |	     |  5.0	|
+-----------------------------------------------------------------------+


+-----------------------------------------------------------------------+
| Software Product				 |  Version  | Release  |
+-----------------------------------------------------------------------+
|ISPF/VM					 |     2     |  2.0  	|
+-----------------------------------------------------------------------+
|ISPF/PDF					 |     2     |  2.0  	|
+-----------------------------------------------------------------------+
|NCCF						 |     2     |  1.0 	|
+-----------------------------------------------------------------------+
|NETVIEW					 |     1     |  1.0 	|
|						 |	     |  2.0	|
+-----------------------------------------------------------------------+
|IBM DOS/VSE Environment			 	      		|
+-----------------------------------------------------------------------+
|VSE/SP						 |     2     |  1.6 	|
+-----------------------------------------------------------------------+
|VSE/ICCF					 |     2     |  1.0 	|
+-----------------------------------------------------------------------+
|ISPF/VSE					 |     1     |  1.0 	|
+-----------------------------------------------------------------------+
|ISPF/PDF					 |     1     |  1.0     |
+-----------------------------------------------------------------------+
|CICS/DOS/VS					 |     1     |  6.0	|
+-----------------------------------------------------------------------+
|NCCF						 |     2     |  2.0   	|
+-----------------------------------------------------------------------+

Since the introduction of this software, other configurations may have been 
tested.  Please contact your local DIGITAL office for up-to-date information 
regarding listed configurations.

PREREQUISITE SUPPORT

A Network Profile and a DECnet Customer Support Plan (where appropriate) must 
be prepared jointly by DIGITAL and the customer covering all VMS nodes that 
wish to install the 3270 DS Programming Interface. 

In order for this product to be DIGITAL supported, the customer must have a 
DIGITAL supported DECnet/SNA gateway or VMS/SNA configuration. 

To have a DIGITAL supported DECnet/SNA gateway configuration or VMS/SNA 
configuration, purchase of the Gateway Orientation/Installation Service 
(QSF0x-SZ) is REQUIRED in conjunction with the customer's first purchase of the 
DECnet/SNA gateway.

HARDWARE REQUIREMENTS 

oo VAX, MicroVAX or VAXstation configuration as specified in the System Support 
  Addendum (SSA 26.87.05-x).

oo Any properly configured DECnet/SNA gateway system as specified in the System 
  Support Addendum (SSA 26.87.05-x).

SOFTWARE REQUIREMENTS*

In a DECnet/SNA Gateway Environment:

oo VMS Operating System 

oo DECnet-VAX 

In a VMS/SNA environment:

oo VMS Operating System

oo VMS/SNA Software

DECnet/SNA VMS 3270 Data Stream Programming Interface software requires one of 
the following products:

oo VMS/SNA
oo DECnet/SNA Gateway-CT
oo DECnet/SNA Gateway-ST
oo DECnet/SNA Gateway

* Refer to the System Support Addendum for availability and required versions 
  of prerequisite/optional software (SSA 26.87.05-x).

ORDERING INFORMATION

Software Licenses: QL-363A*-**
Software Media: QA-363A*-**
Software Documentation: QA-363AA-GZ
Software Product Services: QT-363A*-**

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

SOFTWARE LICENSING

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

LICENSE MANAGEMENT FACILITY SUPPORT

This layered product supports the VMS 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 License 
Management Facility manual of the VMS Operating System documentation set.

For more information about DIGITAL's licensing terms and policies, contact your 
local DIGITAL office.

SOFTWARE PRODUCT SERVICES

A variety of service options are available.  For more information on these or 
other services, 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.


BH-ET78F-TE
