IBM CICS Transaction Server for z/OS

A powerful, mixed-language application server that runs on IBM z/OS®

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Learn how CICS TS 6.3 supports OpenTelemetry, VS Code, AI agents, security and more.

Watch the video education by CICS experts to discover how to get started with new features in CICS TS 6.3.

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Overview

IBM CICS® Transaction Server, often called CICS, is a world-class, secure, powerful, scalable, mixed-language application server platform used for hosting your transactional enterprise applications in a hybrid architecture. It provides an environment to host applications offering services to address concerns like security, transactionality or data exchange between new and existing applications. CICS can provide these services to applications composed of components written in different programming languages allowing for modernization using languages that best fit your developers’ skills and your business’s needs.

Upgrading to the newest release Updates and enhancements for CICS
Security

Robust controls to secure transactions, resources and networks in tandem with your z/OS security manager and compliance authority.

Scalablity

Applications that efficiently scale and prioritize workloads that deliver the full potential of your IBM Z and z/OS sysplex to meet your enterprise needs.

Flexibility

A choice of familiar languages ​​and frameworks to integrate and modernize your IBM Z applications and data.

High performance

Provides an optimized architecture to handle high transaction volumes with low latency and close proximity to data for robust enterprise business processes and SLA compliance.

Features

An engineer attentively observes and tracks information on a computer system

OpenTelemetry support brings native distributed tracing to CICS workloads, giving teams end‑to‑end visibility across hybrid‑cloud environments. With this capability, performance tuning and root‑cause analysis become simpler and faster, as every transaction can be followed through the entire service chain without additional instrumentation. The built‑in integration also feeds traces into your existing monitoring tools, enabling proactive alerting and a unified view of system health. By embedding observability directly into CICS, developers and operators can quickly identify bottlenecks, reduce downtime, and continuously improve service performance.

Explore CICS and OpenTelemetry
Coworkers at a desk

VS Code Marketplace extensions related to CICS application development are now supported, giving developers a rich ecosystem of linters, debuggers, and productivity tools directly inside their IDE. CICS TS lets developers choose the IDE that best fits their workflow—Eclipse or Visual Studio Code (VS Code)—to build modern CICS applications. The VS Code experience is streamlined with a clean layout, IBM‑provided extensions, and Zowe plug‑ins that simplify code authoring, debugging, and deployment. Quick‑start guides walk you through configuring secure connections to z/OS systems and CICS regions, while built‑in snippets and templates accelerate common tasks. By offering support for extensions running on lightweight, highly customizable editor alongside the traditional Eclipse environment, CICS TS 6.3 boosts developer productivity, reduces onboarding time, and enables faster delivery of business‑critical services.

Learn what's new for the developer experience
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The MCP server and associated tooling enable seamless integration of AI agents into transactions, allowing developers to embed intelligent capabilities without leaving the CICS environment. Integrated tooling and libraries streamline coding, testing, and deployment, letting teams deliver value faster. Pre-built CICS TS agents, provided as part of watsonx Assistant for Z, provide rapid access to expert knowledge and best practice recommendations from the IBM development team, which combined with live system data significantly reduce the time and effort needed to understand, configure, optimise and troubleshoot your CICS environment.

Explore CICS and AI Explore CICS and the Model Context Protocol
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CICS administrators can optimize applications with thread‑safe access to shared data tables and lower SMF data volumes. Automation is expanded through CICS policies, Ansible playbooks, and IBM Z capabilities, delivering stronger resilience and scalability while cutting operational expenses.

Learn What's new for resilience
Administrator in a testing center

CICS TS introduces built‑in Zero‑Trust networking capabilities that protect every TCP/IP connection out‑of‑the‑box. By integrating AT‑TLS, credentials and cipher suites are managed centrally, eliminating scattered credential sprawl and simplifying compliance. A new SIT parameter forces all CICS TCP/IP traffic to be encrypted—either by CICS itself or via AT‑TLS—ensuring data‑in‑motion is always protected. The CICS Explorer security dashboard adds a “to‑do list” that automatically surfaces gaps in RACF (or other security manager) definitions, guiding teams through incremental remediation. Together, these enhancements give you a single, auditable security layer that aligns with Zero‑Trust principles and reduces operational overhead.

Learn What's new for security
Young Programmer Coding At Desk

Developers gain modern language support (latest Java, Jakarta EE, Spring Boot, and Node.js) that accelerates the modernization and extension of CICS‑based applications.

Explore What's new for the developer experience
An engineer attentively observes and tracks information on a computer system

OpenTelemetry support brings native distributed tracing to CICS workloads, giving teams end‑to‑end visibility across hybrid‑cloud environments. With this capability, performance tuning and root‑cause analysis become simpler and faster, as every transaction can be followed through the entire service chain without additional instrumentation. The built‑in integration also feeds traces into your existing monitoring tools, enabling proactive alerting and a unified view of system health. By embedding observability directly into CICS, developers and operators can quickly identify bottlenecks, reduce downtime, and continuously improve service performance.

Explore CICS and OpenTelemetry
Coworkers at a desk

VS Code Marketplace extensions related to CICS application development are now supported, giving developers a rich ecosystem of linters, debuggers, and productivity tools directly inside their IDE. CICS TS lets developers choose the IDE that best fits their workflow—Eclipse or Visual Studio Code (VS Code)—to build modern CICS applications. The VS Code experience is streamlined with a clean layout, IBM‑provided extensions, and Zowe plug‑ins that simplify code authoring, debugging, and deployment. Quick‑start guides walk you through configuring secure connections to z/OS systems and CICS regions, while built‑in snippets and templates accelerate common tasks. By offering support for extensions running on lightweight, highly customizable editor alongside the traditional Eclipse environment, CICS TS 6.3 boosts developer productivity, reduces onboarding time, and enables faster delivery of business‑critical services.

Learn what's new for the developer experience
computer programmers using desktop PC at office desk

The MCP server and associated tooling enable seamless integration of AI agents into transactions, allowing developers to embed intelligent capabilities without leaving the CICS environment. Integrated tooling and libraries streamline coding, testing, and deployment, letting teams deliver value faster. Pre-built CICS TS agents, provided as part of watsonx Assistant for Z, provide rapid access to expert knowledge and best practice recommendations from the IBM development team, which combined with live system data significantly reduce the time and effort needed to understand, configure, optimise and troubleshoot your CICS environment.

Explore CICS and AI Explore CICS and the Model Context Protocol
woman silhouette looking at a big screen

CICS administrators can optimize applications with thread‑safe access to shared data tables and lower SMF data volumes. Automation is expanded through CICS policies, Ansible playbooks, and IBM Z capabilities, delivering stronger resilience and scalability while cutting operational expenses.

Learn What's new for resilience
Administrator in a testing center

CICS TS introduces built‑in Zero‑Trust networking capabilities that protect every TCP/IP connection out‑of‑the‑box. By integrating AT‑TLS, credentials and cipher suites are managed centrally, eliminating scattered credential sprawl and simplifying compliance. A new SIT parameter forces all CICS TCP/IP traffic to be encrypted—either by CICS itself or via AT‑TLS—ensuring data‑in‑motion is always protected. The CICS Explorer security dashboard adds a “to‑do list” that automatically surfaces gaps in RACF (or other security manager) definitions, guiding teams through incremental remediation. Together, these enhancements give you a single, auditable security layer that aligns with Zero‑Trust principles and reduces operational overhead.

Learn What's new for security
Young Programmer Coding At Desk

Developers gain modern language support (latest Java, Jakarta EE, Spring Boot, and Node.js) that accelerates the modernization and extension of CICS‑based applications.

Explore What's new for the developer experience
Compare editions

Whether you want to try out the new features of CICS Transaction Server for the first time or set up a production system, IBM provides an edition to suit your needs.

Download the open beta to get early access to new capabilities
Editions Developer trial

Try CICS in your environment for free today with world-class IBM support.

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MLC

A licensed, full-function product for enterprise clients’ production use with world-class IBM support.

VUE

A licensed, full-function product for production use on new workloads with world-class IBM support.

Licensing options

No charge

Monthly license charge

One-time charge

Task capacity

Maximum 30 user tasks

Unlimited number of tasks

Unlimited number of tasks

Product expiration date

Expires 90 days after ordering

No expiration

No expiration

Usage

Non-production use only

Production use

Production use

IBM Software Subscription and Support (S&S)

Severity 3 and 4 only

*Prices shown are indicative, may vary by country, exclude any applicable taxes and duties, and are subject to product offering availability in a locale.

Technical details

Before you can install CICS Transaction Server for z/OS, there are some preparation steps to do, such as:

  • Choosing the distribution package
  • Checking system requirements
  • Upgrading CICS explorer
See all the prerequisites

Scenarios

Atom feeds

CICS can expose files as Atom feeds so that external parties can read and update the contents of the files. Event processing can monitor any changes made to the files.

Running existing apps on open TCBs

Threadsafe capabilities of CICS Transaction Server for z/OS could enable you to run more of your existing applications on open TCBs without changing their code.

Related products

IBM Z Security and Compliance Center

A browser-based application to automate evidence collection of compliance-relevant facts from IBM Z platforms.

IBM z/OS Connect

Truly RESTful APIs to and from your IBM Z mainframe.

IBM CICS Performance Analyzer for z/OS

Gain insight with comprehensive analysis and flexible reporting.

IBM Developer for z/OS

A comprehensive, robust toolset for developing z/OS applications.

Take the next step

Upgrade your IBM CICS Transaction Server systems to latest version.

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