programs use CICS macros, which is very useful when you must determine your scope-of-effort.

The CICS Application Migration Aid (5695-061), should be used to assist customers migrating macro-level programs to command-level programs. Please review the manual CICS/VSE Application Migration Aid Guide V2, SC33-1901 for more detail.

COBOL and CICS Command Level Conversion Aid for VSE (CCCA) - CCCA assists in the removal of BLL cell processing to ANSI 85 COBOL processing (5785-CCC). Please review the manual CCCA/VSE Installation and User′s Guide, SC26-8269 for more details.

During the planning and/or application conversion process you may find it difficult to convert your macro programs. You may find other aids to help you with the conversion and/or consider the coexistence of CICS/VSE and CICS TS systems.

6.1.13 CICS/VSE and TS Coexistence Considerations

As part of the migration you may need to consider the coexistence of a CICS/VSE system with a CICS TS system via an ISC connection. The reasons for this may vary from parallel testing, migrating of data, to function shipping requirements for DL/I and so on. Still, you should understand functions that will help the cooperative systems.

If you allow the send and receive prefixes to default, CICS creates the last three characters of the session names from the alphanumeric characters A through Z, and 1 through 9. These three-character identifiers begin with the letters AAA, and continue in ascending sequence until the number of session entries reaches the limit set by the SEND- or RECEIVECOUNT value. This method is the same as that for APPC sessions.

To maintain compatibility with earlier releases, this change is optional. You can continue to define your own prefixes for the send and receive sessions, in which case CICS generates the terminal control table entries (TCTTEs) for session names in the same way as for earlier releases.

Please review the CICS Intercommunication Guide, SC33-1698 which provides definitions and guidelines for intersystems connections.

6.1.14 Testing and Problem Determination Considerations

You should consider that due to the change in operating systems and CICS′ s preparation, education and training should be completed before your installation and test begin. However, here are few items to consider with the process.

There are major differences in:

∙

∙

∙

∙

initialization messages.

system initialization parameters.

initialization error recovery.

messages and codes issued by different systems, and in the operator actions they require.

∙handling output from CICS monitoring.

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IBM OS/390 manual CICS/VSE and TS Coexistence Considerations, Testing and Problem Determination Considerations
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OS/390 specifications

IBM OS/390, a versatile operating system, was a cornerstone in enterprise environments and played a pivotal role in mainframe computing. Released in the mid-1990s, OS/390 combined the strengths of IBM's MVS (Multiple Virtual Storage) with new features and enhancements, targeting scalability, reliability, and performance in demanding business applications.

One of the key features of OS/390 was its robust support for multiple users and processes. The system allowed thousands of concurrent users to access applications and data, ensuring high availability and minimizing downtime—a critical requirement for many large organizations. This scalability was supported through various enhancements in memory management and processor scheduling, enabling optimal resource allocation across diverse workloads.

OS/390 was known for its superior workload management capabilities. The Workload Manager (WLM) component allowed administrators to define service policies, specifying how system resources would be allocated according to the priority of tasks. This ensured that critical business processes received the necessary resources while less critical tasks were managed more flexibly.

Another significant characteristic of OS/390 was its commitment to security. The operating system provided comprehensive security features, including user authentication, data encryption, and auditing capabilities. This focus on security was vital for organizations handling sensitive data, ensuring compliance with regulations and safeguarding against unauthorized access.

OS/390 also supported advanced technologies that facilitated integration and development. The system included features like the IBM CICS (Customer Information Control System) for transaction processing and IMS (Information Management System) for database management. These technologies allowed organizations to build robust, high-performance applications tailored to specific business needs.

The ease of network integration was another strength of OS/390. With the advent of the Internet and global connectivity, OS/390 systems could easily interface with various network protocols, enabling businesses to operate in a connected world. This inclusion paved the way for many organizations to expand their capabilities and offer new services, driving digital transformation.

In conclusion, IBM OS/390 represented a significant advancement in mainframe technology, combining scalability, security, and robust workload management. Its rich feature set and support for critical enterprise applications solidified its role as a vital component of many organizations' IT infrastructures, ensuring they could meet their operational challenges head-on while supporting future growth. As technology continues to evolve, the legacy of OS/390 remains influential in the realm of computing.
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