Network Job Entry (NJE)

Application Programming Interfaces

Accounting

RAS Characteristics

Testing Techniques

Note: The comparison is based on the functions provided within VSE/POWER. Therefore, it is not a complete overview of all functions available in JES2.

10.3.1.1 Multiple System Support

In POWER, the Spool File can be shared between multiple VSE/POWER systems using the ªShared Spoolº feature.Multi-access spool or MAS is a standard feature of JES2. Even in a single system environment, JES2 assumes there are multiple systems (called members) sharing spool and checkpoint.

JES2 allows a maximum of 32 members in an MAS, compared with POWER which allows only four. The JES2 members usually correspond to an MVS system, but you can have multiple JES2 subsystems (members) on the same MVS system.

Both VSE/POWER and OS/390 support the sharing of user files between multiple systems with integrity. This is supported by Global Resource Serialization (GRS) with OS/390. See OS/390 V1R3.0 MVS Planning - Global Resource Serialization, GC28-1759 for details.

10.3.2 Input Service

As with POWER, jobs may be submitted to JES2 from many sources. Here are some comparisons:

Table 11. JES2 Input Sources (compared to POWER)

Input From:

POWER

JES2

JES2 Comments

 

 

 

 

Local Card Reader

Y

Y

JES2 supports 2501, 2540,

 

 

 

3505 & 3525

 

 

 

 

Disk

Y (SLI)

Y

Use IEBGENER or IEBEDIT

 

 

 

(RDRxx proc)

 

 

 

 

Tape

Y

Y

Use IEBGENER or IEBEDIT

 

 

 

or RDRxx proc

 

 

 

 

3540 Diskette

Y

N

3540 Reader Utility no

Reader

 

 

longer supported

 

 

 

 

Remote BSC & SNA

Y

Y

See 10.3.6.2, ªRemote

Terminal

 

 

Workstation Definitionsº on

 

 

 

page 219

 

 

 

 

Submit Function

Y (ICCF)

Y

TSO/E See 7.4, ªSubmitting

 

 

 

Jobs for Batch Executionº

 

 

 

on page 162

 

 

 

 

Internal Reader

Y

Y

// DD SYSOUT=

 

 

 

(x,INTRDR)

 

 

 

 

NJE Nodes

Y

Y

See 10.3.7.1, ªNJE

 

 

 

Definitionsº on page 221

 

 

 

 

212VSE to OS/390 Migration Workbook

Page 236
Image 236
IBM OS/390 manual Input Service, Multiple System Support, JES2 Input Sources compared to Power, Input From, JES2 Comments

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.