Understanding the iWay Transaction for IMS

Topics:

The following diagram illustrates the adapter connection to the mainframe using TCP/IP.

The adapter is the component that connects to IMS/TM. It is hosted in a container that supports events. The adapter enables the following functions:

The adapter enables you to invoke an IMS/TM transaction by sending a request and retrieving the response.

IMS Connect was introduced with IMS Version 7.1 to execute IMS/TM transactions from a TCP/IP client.

At design-time, you describe the request and response messages by mapping them to Cobol File Descriptions. You communicate with IMS/TM through either TCP/IP or CRM gateway.

IMS/TM Transactions

There are two types of IMS/TM transactions:

  • Non-conversational.
  • Conversational (for example, when a user interacts with a terminal screen (3270).

The iWay Transaction Adapter for IMS can process conversational transactions when using TCP/IP. To execute 3270 conversational programs, you require a screen scraper, such as the iWay Emulation Adapter for 3270. For many years, IMS/TM applications were structured so that the business processing, as opposed to the screen dialogue, was in non-conversational transactions. In many cases, executing a non-conversational transaction is recommended for application integration. When the application program must be integrated in a conversation, and multiple requests are presented across a single process, the iWay Transaction Adapter for IMS can maintain the processing required for this IMS conversational transaction. Screen-scraping for 3270 cannot be involved in this integration because the adapter provides application integration only.

Local transactions have limited support. IMS resources are not involved in the local transactions.

The iWay Transaction Adapter for IMS also supports more complex transactional scenarios involving multiple service calls, commits, and rollbacks, when connecting to IMS via a CRM gateway.

Software Requirements for the Adapter

This section lists the software requirements for the iWay Transaction Adapter for IMS:

  • z/OS Version 1.2, 1.3, 1.4, 1.5, 1.6, and 1.7.

For TCP/IP:

  • IMS Version 4, 5, 6, 7, 8, and 9.
  • IMS Connect and Open Transaction Manager Access (OTMA) installed and configured on the remote IMS/TM system.