Backlevel Hardware Support, Btam Product Installation

∙On the PCCU statement there are DUMPDS, MDUMPDS and CDUMPDS keywords which refer to various data sets which will contain NCP dumps. Code the names of the DD statements in the VTAM procedure which will point to the actual data sets.

∙On the BUILD statement, the LOADLIB keyword specifies the DD name of the data set which VTAM will use to find the NCP when the time comes to load it. The name you code must be in the VTAM start procedure (NCPLOAD in the example).

9.2.3Backlevel Hardware Support

Current releases of NCP do not support older 37XX hardware. Many of these boxes are still in service, so if back level 37XX hardware support is required the following NCP versions remain orderable for both VSE and OS/390:

∙

NCP V4R3.1 (5668-854) - 3725 support

NCP V5R4.0 (5668-738) - 3720 support

You should be aware, however, that if you are using NCP V4R2 (or below) on a 3725 or 3720, the upgrade to a supported version will use a lot more NCP storage. NCP V4R3 introduced support for independent LUs for the first time, and the resulting increase in module size (even if ILUs are not used) can add hundreds of Kilobytes to your requirements.

You should also be aware that neither the 3725 nor the 3720 can support APPN or HPR.

9.3 BTAM

9.3.1 Product Installation

Differences in the installation procedures of BTAM for VSE and OS/390 are basically the same as those for VTAM and NCP. The VSE BTAM-ES product

(5746-RC5) and the OS/390 BTAM/SP product (5665-279) are very similar in the MACRO names they use and the function they provide. The differences are in the parameters they require on the MACROS. For further information refer to BTAM-ES Programming Reference, SC38-0293 for VSE and BTAM/SP, SC27-0604 for OS/390.

9.3.2 Usage

CICS is the most common user of BTAM. Although BTAM continues to be supported by both VSE and OS/390, note that there is no support for devices and controllers accessed using BTAM in any CICS version after CICS/MVS Version 2 Release 1.2. The recommendation here is to migrate these devices to VTAM.

9.4 Migrating TCP/IP

TCP/IP provides the ability to merge differing physical networks while giving users a common suite of functions. It allows interoperability between equipment supplied by multiple vendors on multiple platforms. TCP/IP is the protocol in an open networking world including the Internet.

Chapter 9. Telecommunications Subsystems 193

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.

IBM OS/390 manual Backlevel Hardware Support, Btam Product Installation, Usage, Migrating TCP/IP

Models: OS/390