JES3plus is a licensed, derivative work based on IBM®’s z/OS® JES3 V2R4 source code. Created with customers in mind, JES3plus provides existing JES3 customers a common-sense alternative to a costly and potentially risky JES2 conversion. Customer implementation involves a trivial migration to a fully supported product, with a road map for enhancements, no planned end of life, and no additional licensing costs.

JES3plus Partners

Phoenix Software works with our partner Independent Software Vendors (ISV) to bring value to JES3plus. Learn about ISV applications that support JES3plus.

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What is the Job Entry Subsystem (JES)

The Job Entry Subsystem (JES) is a component of IBM’s z/OS® operating system responsible for managing batch workloads. Minimum JES functionality includes reading jobs into the system, selecting them for processing, managing/printing their output, and purging them from the system. Uniquely, JES3 provided multisystem coupling, intelligent tape sharing, resource routing, load balancing, dynamic initiators, pre-execution device setup, job networks, deadline scheduling, multisystem consoles, a JESplex-wide merged log, and other capabilities that simplified the operation and management of loosely-coupled systems nearly two decades before the emergence of sysplex support in the base operating system. Most of these unique JES3 functions continue to have relevance even today.


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Road Map

JES3plus is a plug-compatible solution for IBM JES3 customers not wishing to embark on a costly and potentially risky JES2 conversion. This means:

  • User exits, source modifications (if any), and message automation continue to work unchanged
  • Operator commands are unchanged
  • Job and device setup are fully supported and continue to work unchanged
  • Tape high-watermark setup is fully supported and continues to work unchanged
  • NJE and RJP partner interactions with your systems are unchanged
  • DevTest and production JCL continue to work unchanged
  • Production control procedures continue to work unchanged
  • Log and output post-processing scripts continue to work unchanged
  • JES3’s often superior performance characteristics are unchanged

Enhancements released:

  • I/O performance improvement (ACKD support)
  • I/O performance improvement (zHPF support)

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Additional enhancements are planned for future releases.

A JES3plus Migration Success Story

“We migrated from JES3 to JES3plus this year which was one of the most crucial migrations we have ever done as JES3 underpins the entire operating system…

“…In all we raised four tickets with Phoenix over different issues regarding JES3plus and we got extremely prompt and accurate replies in every case. Consequently, the JES3 to JES3plus migration went extremely smoothly and was on time which was not how I envisaged such a major migration.

Phoenix are also convening a user council to discuss enhancements to the JES3plus product which has been unheard of in the last 5 years or so.”

— A Global Media Company

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The Journey

z/OS 2.3 preview announcement contains no new JES3 function.

The grapevine indicates some sort of JES3 announcement is imminent. The “Group of 16” JES3 customers is assembled as a result.

IBM’s SOD is released affirming JES2 is their “strategic” spooler. One-on-one calls begin between IBM and its JES3 customers.

SHARE Providence: IBM acknowledges during a keynote Q&A, IBM is trying to get rid of JES3. Ad-hoc discussions between customers and IBM occur during the event. IBM agrees to a call with the Group of 16.

Initial call between IBM and the Group of 16 occurs. Some customers privately suggest Phoenix Software should take on JES3. We thought such ideas were premature.

SHARE Sacramento: No on-site JES3 discussions. The Group of 16 has been renamed to the SHARE JES3 Task Force by SHARE who now provides resources. IBM continues one-on-one calls with its JES3 customers throughout the year and many are shared and re-capped among the group via periodic calls.

SHARE St Louis: IBM z/OS Development leadership changes. New leadership agrees to participate in a conference call with the JES3 Task Force and bring along JES3 experts.

IBM assigns an offering manager for JES3 discussions. Customers communicate their business concerns to IBM.

IBM’s SOD is released announcing the release following z/OS 2.4 will be last to offer JES3. This begins a 10½ year countdown to a final JES3 sunset.

SHARE Phoenix: Many customers reaffirm their hope/desire for Phoenix Software to take on JES3. Phoenix Software executive management team send a letter to IBM entitled, “Possible JES3 Partnership Opportunity,”. They agree to meet.

Initial conversations are held between IBM and Phoenix Software in Poughkeepsie.

First proposal is presented to IBM by Phoenix Software team in Poughkeepsie and is well received. Both sides agree to proceed to the next steps.

Revised proposal is presented to IBM by Phoenix Software team in Poughkeepsie based on completed due diligence and is well received. Both sides agree to proceed to the next steps.

Deal points are agreed to, contracts are presented and fully executed, and source code is transferred.

Phoenix Software International announces
IBM JES3 licensing agreement.

V1R0 became generally available.

ACKD I/O driver, the first enhancement since early 2015, made available via the service stream

zHPF I/O enhancement made available via the service stream


V1R1, the first release to contain enhancements since early 2015, became generally available.

JES3plus Open Trusted Technology Provider Standard (O-TTPS) Certification

Phoenix Software International, Inc.’s IBM Z system management products are certified under the Open Group O‑TTPS Certification Program: Self-Assessed tier and meets the requirements of the Open Trusted Technology Provider™ Standard Version 1.1.1 and ISO/IEC 20243:2018.

The O-TTPS, a standard of The Open Group®, provides a set of guidelines, recommendations, and requirements that help assure against maliciously tainted and counterfeit products throughout commercial off-the-shelf (COTS) information and communication technology (ICT) product lifecycles. Phoenix Software is committed to providing customers with the assurance that our certified products, (E)JES, JES3plus, and PHX-BDT, can be trusted for their business critical processes.

System Management Products

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