Editing CICS (section)

==History==
[[Image:CICS.svg|thumb|left|Chart depicting high-level architecture of CICS (in French)]]
CICS was preceded by an earlier, single-threaded transaction processing system, [[IBM MTCS]]. An 'MTCS-CICS bridge' was later developed to allow these transactions to execute under CICS with no change to the original application programs.
IBM's Customer Information Control System (CICS) was first developed in conjunction with [[Michigan Bell]] in 1966.<ref name="IBM">{{cite web |title=IBM archives |date=23 January 2003 |url=https://www.ibm.com/ibm/history/history/year_1968.html |publisher=IBM |access-date=6 December 2022}}</ref> Ben Riggins was an IBM systems engineer at Virginia Electric Power Co. when he came up with the idea for the online system.<ref name="Esm">{{cite web |title=ESM Mainframe hall of fame |url=https://www.enterprisesystemsmedia.com/mainframehalloffame |publisher=ESM |access-date=6 December 2022}}</ref>

CICS was originally developed in the United States out of the IBM Development Center in [[Des Plaines, Illinois]], beginning in 1966 to address requirements from the public utility industry. The first CICS product was announced in 1968, named ''Public Utility Customer Information Control System'', or PU-CICS.  It became clear immediately that it had applicability to many other industries, so the Public Utility prefix was dropped with the introduction of the first release of the CICS [[Software as a Product|Program Product]] on July 8, 1969, not long after [[IBM Information Management System|IMS]] [[database management system]].

[[Image:C Block, IBM Hursley Laboratory - geograph.org.uk - 969045.jpg|thumb|right|IBM Hursley, where much of the CICS development has been done, 2008]]

For the next few years, CICS was developed in Palo Alto and was considered a less important "smaller" product than IMS which IBM then considered more strategic. Customer pressure kept it alive, however. When IBM decided to end development of CICS in 1974 to concentrate on IMS, the CICS development responsibility was picked up by the [[IBM Hursley]] site in the United Kingdom, which had just ceased work on the [[PL/I]] compiler and so knew many of the same customers as CICS. The core of the development work continues in Hursley today alongside contributions from labs in India, China, Russia, Australia, and the United States.

===Early evolution===
CICS originally only supported a few IBM-brand devices like the 1965 [[IBM 2741]] Selectric (golf ball) typewriter-based terminal. The 1964 [[IBM 2260]] and 1972 [[IBM 3270]] [[video display terminal]]s were widely used later.

In the early days of IBM mainframes, computer software was free{{snd}} bundled at no extra charge with [[computer hardware]]. The [[OS/360]] operating system and application support software like CICS were "open" to IBM customers long before the [[open-source software]] initiative. Corporations like Standard Oil of Indiana (Amoco) made major contributions to CICS.

The IBM Des Plaines team tried to add support for popular non-IBM terminals like the [[ASCII]] [[Teletype Model 33]] ASR, but the small low-budget software development team could not afford the $100-per-month hardware to test it. IBM executives incorrectly felt that the future would be like the past, with [[batch processing]] using traditional [[punch cards]].

IBM reluctantly provided only minimal funding when public utility companies, banks and credit-card companies demanded a cost-effective interactive system (similar to the 1965 [[IBM Airline Control Program]] used by the American Airlines [[Sabre (computer system)|Sabre]] [[computer reservation system]]) for high-speed data access-and-update to customer information for their telephone operators (without waiting for overnight batch processing punch card systems).

When CICS was delivered to Amoco with Teletype Model 33 ASR support, it caused the entire OS/360 operating system to crash (including non-CICS application programs). The majority of the CICS Terminal Control Program (TCP{{snd}} the heart of CICS) and part of OS/360 had to be laboriously redesigned and rewritten by Amoco Production Company in Tulsa Oklahoma. It was then given back to IBM for free distribution to others.

In a few years,{{when|date=November 2012}} CICS generated over $60 billion in new hardware revenue for IBM, and became their most-successful mainframe software product.

In 1972, CICS was available in three versions{{snd}} DOS-ENTRY (program number 5736-XX6) for [[DOS/360 and successors|DOS/360]] machines with very limited memory, DOS-STANDARD (program number 5736-XX7), for DOS/360 machines with more memory, and OS-STANDARD V2 (program number 5734-XX7) for the larger machines which ran OS/360.<ref>{{cite book |url=http://bitsavers.org/pdf/ibm/370/CICS/GH20-1028-3_CICS_General_Information_Manual_Dec72.pdf |title=Customer Information Control System (CICS) General Information Manual |location=White Plains, New York |publisher=[[IBM]] |date=December 1972 |id=GH20-1028-3 |access-date=2016-04-01 |archive-date=2019-05-29 |archive-url=https://web.archive.org/web/20190529212532/http://bitsavers.org/pdf/ibm/370/CICS/GH20-1028-3_CICS_General_Information_Manual_Dec72.pdf |url-status=live }}</ref>

In early 1970, a number of the original developers, including Ben Riggins (the principal architect of the early releases) relocated to California and continued CICS development at IBM's [[Palo Alto, California|Palo Alto]] Development Center. IBM executives did not recognize value in software as a revenue-generating product until after federal law required software [[unbundling]]. In 1980, IBM executives failed to heed Ben Riggins' strong suggestions that IBM should provide their own [[EBCDIC]]-based operating system and integrated-circuit [[microprocessor]] chip for use in the [[IBM Personal Computer]] as a CICS [[thin client|intelligent terminal]] (instead of the incompatible Intel chip, and immature [[ASCII]]-based Microsoft 1980 [[DOS]]).

[[Image:Librarian listing of CICSGEN module.jpg|thumb|right|Beginning of a CICSGEN stage one module, 1982]]

Because of the limited capacity of even large processors of that era every CICS installation was required to assemble the source code for all of the CICS system modules after completing a process similar to [[system generation]] (sysgen), called ''CICSGEN'', to establish values for conditional assembly-language statements. This process allowed each customer to exclude support from CICS itself for any feature they did not intend to use, such as device support for terminal types not in use.

CICS owes its early popularity to its relatively efficient implementation when hardware was very expensive, its multi-threaded processing architecture, its relative simplicity for developing terminal-based real-time transaction applications, and many open-source customer contributions, including both debugging and feature enhancement.

===Z notation===
Part of CICS was formalized using the [[Z notation]] in the 1980s and 1990s in collaboration with the [[Oxford University Computing Laboratory]], under the leadership of [[Tony Hoare]]. This work won a [[Queen's Awards for Enterprise|Queen's Award]] for Technological Achievement.<ref>{{Cite book|last=King|first=Steve|editor-last=Hayes|editor-first=Ian|title=Specification Case Studies|year=1993|publisher=Prentice Hall|location=New York|pages=202–213|chapter=The Use of Z in the Restructure of IBM CICS|edition=2nd|isbn=978-0-13-832544-2}}</ref>

===CICS as a distributed file server===
In 1986, IBM announced CICS support for the record-oriented file services defined by [[Distributed Data Management Architecture]] (DDM). This enabled programs on remote, network-connected computers to create, manage, and access files that had previously been available only within the CICS/MVS and CICS/VSE transaction processing environments.<ref>{{cite journal |title=IBM Gives PC Programs Direct Mainframe Access: PC Applications Can Alter Files |journal=[[InfoWorld]] |date=1987-02-23 |last=Warner |first=Edward |volume=9 |issue=8 |page=1 |url=https://books.google.com/books?id=1DAEAAAAMBAJ&pg=PA1 |access-date=2016-04-01 |archive-date=2016-12-24 |archive-url=https://web.archive.org/web/20161224182237/https://books.google.com/books?id=1DAEAAAAMBAJ&pg=PA1 |url-status=live }}</ref>

In newer versions of CICS, support for DDM has been removed. Support for the DDM component of CICS z/OS was discontinued at the end of 2003, and was removed from CICS for z/OS in version 5.2 onward.<ref>{{cite web |url=http://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS214-107 |title=IBM CICS Transaction Server for z/OS, V5.2 takes service agility, operational efficiency, and cloud enablement to a new level |publisher=[[IBM]] |date=2014-04-07 |access-date=2016-04-14 |quote="CICS DDM is no longer available from IBM and support was discontinued, as of December 31, 2003. CICS DDM is no longer available in CICS TS from Version 5.2 onwards." |archive-date=2021-06-15 |archive-url=https://web.archive.org/web/20210615130501/https://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS214-107 |url-status=live }}</ref> In CICS TS for z/VSE, support for DDM was stabilised at V1.1.1 level, with an announced intention to discontinue it in a future release.<ref>{{cite web |url=http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS214-074 |title=IBM z/VSE Central Functions Version 9.2 - z/VSE Version 5.2 |publisher=[[IBM]] |date=April 7, 2014 |access-date=2016-04-14 |quote="Support for CICS Distributed Data Management (DDM) is stabilized in CICS TS for VSE/ESA V1.1.1. In a future release of CICS TS for z/VSE, IBM intends to discontinue support for CICS DDM." |archive-date=2016-03-24 |archive-url=https://web.archive.org/web/20160324192812/http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS214-074 |url-status=live }}</ref> In CICS for z/VSE 2.1 onward, CICS/DDM is not supported.<ref>{{cite web |url=http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS215-362 |title=IBM CICS Transaction Server for z/VSE V2.1 delivers enhancements for future workloads |publisher=[[IBM]] |date=October 5, 2015 |access-date=2016-04-14 |quote="CICS Distributed Data Management (CICS/DDM) is not supported with CICS TS for z/VSE V2.1." |archive-date=2016-04-24 |archive-url=https://web.archive.org/web/20160424205210/http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS215-362 |url-status=live }}</ref>

===CICS and the World Wide Web===
CICS Transaction Server first introduced a native [[Hypertext Transfer Protocol|HTTP]] interface in version 1.2, together with a Web Bridge technology for wrapping green-screen terminal-based programs with an HTML facade. CICS Web and Document APIs were enhanced in CICS TS V1.3 to enable web-aware applications to be written to interact more effectively with web browsers.

CICS TS versions 2.1 through 2.3 focused on introducing [[Common Object Request Broker Architecture|CORBA]] and [[Enterprise JavaBeans|EJB]] technologies to CICS, offering new ways to integrate CICS assets into distributed application component models. These technologies relied on hosting [[Java (programming language)|Java]] applications in CICS. The Java hosting environment saw numerous improvements over many releases. A multi-threaded JVM resource called the JVMSERVER was introduced during the CICS TS version 4.1 release, this was further enhanced to use 64-bit JVM technology in version 5.1. Version 5.1 also saw the introduction of the WebSphere Liberty profile web-container. Ultimately [[IBM WebSphere Application Server|WebSphere Liberty]] was fully embedded into CICS Transaction Server in version 5.3. Numerous web facing technologies could be hosted in CICS using Java, this ultimately resulted in the removal of the native CORBA and EJB technologies.

CICS TS V3.1 added a native implementation of the [[Simple Object Access Protocol|SOAP]] and [[Web Services Description Language|WSDL]] technologies for CICS, together with client side HTTP APIs for outbound communication. These twin technologies enabled easier integration of CICS components with other Enterprise applications, and saw widespread adoption. Tools were included for taking traditional CICS programs written in languages such as [[COBOL]], and converting them into WSDL defined Web Services, with little or no program changes. This technology saw regular enhancements over successive releases of CICS.

CICS TS V4.1 and V4.2 saw further enhancements to web connectivity, including a native implementation of the [[Atom (Web standard)|Atom]] publishing protocol.

Many of the newer web facing technologies were made available for earlier releases of CICS using delivery models other than a traditional product release. This allowed early adopters to provide constructive feedback that could influence the final design of the integrated technology. Examples include the Soap for CICS technology preview SupportPac for TS V2.2, or the ATOM SupportPac for TS V3.1. This approach was used to introduce [[JSON]] support for CICS TS V4.2, a technology that went on to be integrated into CICS TS V5.2.

The [[JSON]] technology in CICS is similar to earlier [[SOAP]] technology, both of which allowed programs hosted in CICS to be wrapped with a modern facade. The JSON technology was in turn enhanced in z/OS Connect Enterprise Edition, an IBM product for composing JSON APIs that can leverage assets from several mainframe subsystems.

Many partner products have also been used to interact with CICS. Popular examples include using the CICS Transaction Gateway for connecting to CICS from [[Java EE Connector Architecture|JCA]] compliant Java application servers, and IBM DataPower appliances for filtering web traffic before it reaches CICS.

Modern versions of CICS provide many ways for both existing and new software assets to be integrated into distributed application flows. CICS assets can be accessed from remote systems, and can access remote systems; user identity and transactional context can be propagated; RESTful APIs can be composed and managed; devices, users and servers can interact with CICS using standards-based technologies; and the IBM WebSphere Liberty environment in CICS promotes the rapid adoption of new technologies.

===MicroCICS===
By January, 1985 a 1969-founded consulting company, having done "massive on-line systems" for Hilton Hotels, FTD Florists, Amtrak, and Budget Rent-a-Car, announced what became ''MicroCICS''.<ref name=MicroCICS.IW86>{{cite magazine |magazine=[[InformationWeek]]
   |title=Unicorn is Betting that CICS is easer and cheaper on a PC
   |author=Paul E. Schindler, Jr.
   |date=October 27, 1986 |pages=41–44}}</ref> The initial focus was the [[IBM XT/370]] and [[IBM AT/370]].<ref>{{cite magazine
|magazine=[[Computerworld]] |date=December 9, 1985 |page=98
|title=Unicorn MicroCICS/RT
|quote=IBM Personal Computer XT/370 family}}</ref>

===CICS Family===
Although when CICS is mentioned, people usually mean CICS Transaction Server, the ''CICS Family'' refers to a portfolio of transaction servers, connectors (called [[CICS Transaction Gateway]]) and CICS Tools.

CICS on distributed platforms—not mainframes—is called [[IBM TXSeries]]. TXSeries is distributed transaction processing middleware. It supports C, C++, COBOL, Java™ and PL/I applications in cloud environments and traditional data centers. TXSeries is available on [[AIX]], Linux x86, [[Microsoft Windows|Windows]], [[Solaris (operating system)|Solaris]], and [[HP-UX]] platforms.<ref>{{cite magazine |magazine=Midrange Systems |page=35
   |title=IBM Get its CICS
   |date=November 10, 1992}}</ref> CICS is also available on other operating systems, notably [[IBM i]] and [[OS/2]]. The z/OS implementation (i.e., CICS Transaction Server for z/OS) is by far the most popular and significant.

Two versions of CICS were previously available for [[VM/CMS]], but both have since been discontinued. In 1986, IBM released ''CICS/CMS'',<ref>"announced .. October of 1985 .. didn't start deliveries until July of this year."</ref><ref name=MicroCICS.IW86/> which was a single-user version of CICS designed for development use, the applications later being transferred to an [[MVS]] or [[DOS/VS]] system for production execution.<ref>{{cite web |url=http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=OC&subtype=NA&htmlfid=897/ENUS5668-795 |title=CICS/CMS |publisher=[[IBM]] |access-date=2016-04-01 |archive-date=2016-04-02 |archive-url=https://web.archive.org/web/20160402054915/http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=OC&subtype=NA&htmlfid=897%2FENUS5668-795 |url-status=live }}</ref><ref>{{cite web |url=http://www-01.ibm.com/common/ssi/rep_ca/5/897/ENUS285-385/index.html |title=CUSTOMER INFORMATION CONTROL SYSTEM/ CONVERSATIONAL MONITOR SYSTEM (CICS/CMS) RELEASE 1 ANNOUNCED AND PLANNED TO BE AVAILABLE JUNE 1986 |publisher=[[IBM]] |date=October 15, 1985 |access-date=2016-04-02 |archive-date=2016-04-02 |archive-url=https://web.archive.org/web/20160402053817/http://www-01.ibm.com/common/ssi/rep_ca/5/897/ENUS285-385/index.html |url-status=live }}</ref> Later, in 1988, IBM released ''CICS/VM''.<ref>{{cite web |url=http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=OC&subtype=NA&htmlfid=897/ENUS5684-011 |title=(CICS/VM) Customer Information Control System / Virtual Machine |publisher=[[IBM]] |access-date=2016-04-01 |archive-date=2016-04-13 |archive-url=https://web.archive.org/web/20160413110835/http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?infotype=OC&subtype=NA&htmlfid=897%2FENUS5684-011 |url-status=live }}</ref><ref>{{cite web |url=http://www-01.ibm.com/common/ssi/printableversion.wss?docURL=/common/ssi/rep_ca/9/897/ENUS287-459/index.html |title=CUSTOMER INFORMATION CONTROL SYSTEM/VIRTUAL MACHINE (CICS/VM) |publisher=[[IBM]] |date=October 20, 1987 |access-date=2016-04-02 |archive-date=2016-04-02 |archive-url=https://web.archive.org/web/20160402054851/http://www-01.ibm.com/common/ssi/printableversion.wss?docURL=%2Fcommon%2Fssi%2Frep_ca%2F9%2F897%2FENUS287-459%2Findex.html |url-status=live }}</ref> CICS/VM was intended for use on the [[IBM 9370]], a low-end mainframe targeted at departmental use; IBM positioned CICS/VM running on departmental or branch office mainframes for use in conjunction with a central mainframe running CICS for MVS.<ref name="Babcock1987">{{cite magazine
|magazine=[[Computerworld]]
|last=Babcock
|first=Charles
|title=VM/SP update eases migration
|url=https://books.google.com/books?id=mUSIMiurpfYC&pg=PP25
|volume=21
|date=2 November 1987
|publisher=IDG Enterprise
|pages=25, 31
|issn=0010-4841
|issue=44
|access-date=30 March 2017
|archive-date=31 March 2017
|archive-url=https://web.archive.org/web/20170331051731/https://books.google.com/books?id=mUSIMiurpfYC&pg=PP25
|url-status=live
}}</ref>

===CICS Tools===
Provisioning, management and analysis of CICS systems and applications is provided by CICS Tools. This includes performance management as well as deployment and management of CICS resources. In 2015, the four core foundational CICS tools (and the CICS Optimization Solution Pack for z/OS) were updated with the release of CICS Transaction Server for z/OS 5.3. The four core CICS Tools: CICS Interdependency Analyzer for z/OS, CICS Deployment Assistant for z/OS, CICS Performance Analyzer for z/OS and CICS Configuration Manager for z/OS.

===Releases and versions===
CICS Transaction Server for z/OS has used the following release numbers:

<!-- Template:Version - for version & release history. Documentation and examples: http://en.wikipedia.org/wiki/Template:Version -->
{| class="wikitable"
|-
! Version
! Announcement Date
! Release Date
! End of Service Date
! Features
|-
| {{Version |o |CICS Transaction Server for OS/390 1.1}}
| {{date|1996-09-10|ISO}}<ref name="ibm.com">{{cite web |title=US - IBM CICS Transaction Server (CICS TS) for OS/390 |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=dd&subtype=sm&appname=ShopzSeries&htmlfid=897/ENUS5655-147 |website=www.ibm.com |access-date=7 May 2022 |date=3 February 2004}}</ref>
| {{date|1996-11-08|ISO}}
| {{date|2001-12-31|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for OS/390 1.2}}
| {{date|1997-09-09|ISO}}<ref name="ibm.com"/>
| {{date|1997-10-24|ISO}}
| {{date|2002-12-31|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for OS/390 1.3}}
| {{date|1998-09-08|ISO}}<ref name="ibm.com"/>
| {{date|1999-03-26|ISO}}
| {{date|2006-04-30|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 2.1}}
| 2001-03-13<ref>{{Cite web |date=2001-05-23 |title=CICS TS for z/OS V2 |url=https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/0/872/ENUSAP01-1070/index.html |access-date=2022-05-13 |website=www.ibm.com |language=en-US}}</ref>
|2001-03-30
| {{date|2002-06-30|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 2.2}}
| {{date|2001-12-04|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS V2.2 Delivers Major Value to All CICS Customers |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS201-354 |website=www.ibm.com |access-date=7 May 2022 |date=4 December 2001}}</ref>
| {{date|2002-01-25|ISO}}
| {{date|2008-04-30|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 2.3}}
| {{date|2003-10-28|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS V2.3 advances towards on demand business |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS203-296 |website=www.ibm.com |access-date=7 May 2022 |date=28 October 2003}}</ref>
| {{date|2003-12-19|ISO}}
| {{date|2009-09-30|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 3.1}}
| {{date|2004-11-30|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS V3.1 offers improved integration, application transformation |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS204-285 |website=www.ibm.com |access-date=7 May 2022 |date=30 November 2004}}</ref>
| {{date|2005-03-25|ISO}}
| {{date|2015-12-31|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 3.2}}
| {{date|2007-03-27|ISO}}<ref>{{cite web |title=CICS Transaction Server for z/OS V3.2 delivers significant innovation for application connectivity |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS207-051 |website=www.ibm.com |access-date=7 May 2022 |date=27 March 2007}}</ref>
| {{date|2007-06-29|ISO}}
| {{date|2015-12-31|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 4.1}}
| {{date|2009-04-28|ISO}}<ref>{{cite web |title=IBM US Announcement Letter |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?subtype=ca&infotype=an&appname=iSource&supplier=897&letternum=ENUS209-135 |website=www.ibm.com |access-date=7 May 2022 |date=28 April 2009}}</ref>
| {{date|2009-06-26|ISO}}
| {{date|2017-09-30|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 4.2}}
| {{date|2011-04-05|ISO}}<ref>{{cite web |title=IBM US Announcement Letter |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS211-080 |website=www.ibm.com |access-date=7 May 2022 |date=5 April 2011}}</ref>
| {{date|2011-06-24|ISO}}
| {{date|2018-09-30|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 5.1}}
| {{date|2012-10-03|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS V5.1 delivers operational efficiency and service agility with cloud enablement |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS212-325 |website=www.ibm.com |access-date=7 May 2022 |date=3 October 2012}}</ref>
| {{date|2012-12-14|ISO}}
| {{date|2019-07-01|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 5.2}}
| {{date|2014-04-07|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS, V5.2 takes service agility, operational efficiency, and cloud enablement to a new level |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS214-107 |website=www.ibm.com |access-date=7 May 2022 |date=7 April 2014}}</ref>
| {{date|2014-06-13|ISO}}
| {{date|2020-12-31|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 5.3}}
| {{date|2015-10-05|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS, V5.3 delivers advances in service agility, operational efficiency, and cloud enablement with DevOps |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS215-363 |website=www.ibm.com |access-date=7 May 2022 |date=5 October 2015}}</ref>
| {{date|2015-12-11|ISO}}
| {{date|2021-12-31|ISO}}
| 
|-
| {{Version |o |CICS Transaction Server for z/OS 5.4}}
| {{date|2017-05-16|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS, V5.4 delivers unparalleled mixed language application serving |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&supplier=897&letternum=ENUS217-113 |website=www.ibm.com |access-date=7 May 2022 |date=16 May 2017}}</ref>
| {{date|2017-06-16|ISO}}
| {{date|2023-12-31|ISO}}
| 
|-
| {{Version |co |CICS Transaction Server for z/OS 5.5}}
| {{date|2018-10-02|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS, V5.5 delivers support for Node.js and further enhancements to CICS Explorer, systems management, and security |url=https://www.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/2/897/ENUS218-352/index.html |website=www.ibm.com |access-date=7 May 2022 |date=2 October 2018}}</ref>
| {{date|2018-12-14|ISO}}
| {{date|2025-09-30|ISO}}
| 
|-
| {{Version |co |CICS Transaction Server for z/OS 5.6}}
| {{date|2020-04-07|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS, V5.6 delivers significant improvements to the developer experience, security, resilience, and management |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&appname=gpateam&supplier=897&letternum=ENUS220-077 |website=www.ibm.com |access-date=6 May 2022 |date=7 April 2020}}</ref>
| {{date|2020-06-12|ISO}}
|
| Support for [[Spring Framework#Spring Boot|Spring Boot]], [[Jakarta EE]] 8, [[Node.js]] 12. New JCICSX API with remote development capability. Security, resilience and management enhancements.
|-
| {{Version |co |CICS Transaction Server for z/OS 6.1}}
| {{date|2022-04-05|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS, 6.1 delivers significant improvements in the areas of developer productivity, security, and management |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?infotype=an&subtype=ca&appname=gpateam&supplier=897&letternum=ENUS222-092 |website=www.ibm.com |access-date=6 May 2022 |date=5 April 2022}}</ref>
| {{date|2022-06-17|ISO}}
|
| Support for [[Java (programming language)|Java]] 11, [[Jakarta EE]] 9.1, Eclipse MicroProfile 5, [[Node.js]] 12, [[Transport Layer Security|TLS]] 1.3. Security enhancements and simplifications. Region tagging.
|-
| {{Version |c |CICS Transaction Server for z/OS 6.2}}
| {{date|2024-04-09|ISO}}<ref>{{cite web |title=IBM CICS Transaction Server for z/OS 6.2 general availability |url=https://www.ibm.com/docs/en/announcements/cics-transaction-server-zos-620-ga-announcement?region=US |website=www.ibm.com |access-date=23 Sep 2024 |date=9 April 2024}}</ref>
| {{nowrap|{{date|2024-06-14|ISO}}}}
|
| 
|-
| colspan="5" | <small>{{Version |l}}</small>
|}
{{Incomplete table|date=May 2022}}