Support | Mainframe Dictionary | C

A glossary of terms important to IBM mainframe machines

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z misc.
If you don't find what you seek,
please let us know.

Please tell us of a term you did not find in the dictionary,
or a definition you would like to see improved.
Term to define:

C:  A programming language developed at Bell Labs in 1972, so named because its predecessor was named B. Unix was written in C, and C’s popularity, both on and off of Unix platforms, peaked in Unix’s early years of widespread use. Still available on most platforms, but most new development is done in one of its object-oriented successors, such as C++, or newer languages like Java or Visual Basic.

C&IR:  Commercial and Industry Relations.

C++:  An object-oriented version of C that has pretty much replaced it. See also C/C++, Visual BASIC.

C/370:  C compiler and library for MVS and VM. Replaced by C/C++ (z/OS) and C for VM/ESA (z/VM).

C/400:  An early C implementation for the AS/400. Replaced by ILE C for AS/400 December 1995. See also System C/400.

C/C++:  An optional, separately priced feature of z/OS, available with or without Debug Tool. The C/C++ IBM Open Class Library is included with z/OS, but is only enabled when C/C++ is licensed.

C2:  A security classification level set by the US National Security Agency (NSA). There are other levels within the Trusted Computer System Evaluation Criteria (TCSEC).

C2T:  See Cable Chaining Technology.

C4 joints:  Controlled Collapse Chip Connection points. The first eserver zSeries 900 used MultiChip Modules (MCM), each with 85,000 C4 joints.

CA1:  Channel Attachment.

CA2:  See Certification Authority.

CAATT:  Computer Assisted Auditing Tools and Techniques. A generic term for software tools to help carry out internal audits.

Cable Chaining Technology:  A technique to drastically reduce the number of cables in rack mounted systems by creating a single chain of cables between systems, through which any system can communicate with any other.

Cable-on-line:  Uses IBM-designated cable modem, software, and switching hardware allowing cable TV systems to provide data services to subscribers, including high speed Internet access. Announced December 1996.

Cabling System:  IBM standard for wiring up sites for compatibility with current and future IBM systems. A laudable attempt, although the initial spec used fat, expensive cables and space-consuming hardware in the wiring closet. Changes to the cable specs (notably use of twisted pair) and more compact closet hardware have made it a better proposition.

Cache/400:  AS/400 PRPQ which allows main memory to be used as a DASD cache. It seems a remarkably silly idea, since main memory is over-expensive for this purpose, and its use requires the kind of expertise which is meant to be unnecessary in the AS/400 environment. Obsolete.

Cache1:  High-speed buffer between a fast device and a slow device. In large IBM systems caching may take place in the CPU (in main or expanded storage), the controller, device head-of-string, or the device itself (e.g., in a track buffer). It is used to reduce access time.

Cache2:  The installation of downloaded applets on a client’s hard drive, to eliminate the need for repeated downloads. Automatic version checking occurs with the server that originally downloaded the applet each time the applet is invoked, to ensure that users are notified when a newer version of the applet is available. (See also smart caching). Static Web pages, previously displayed, may also be cached at the client or at an intermediary caching agent to expedite subsequent accesses.

Cache Fast Write:  Facility on cached DASD controllers to improve the writing performance of DASD. Data is written to cache (although not to a non-volatile medium), thereby removing the need for a program to wait for data to be written to disk before it can continue. Typically used for temporary data (e.g., by DFSORT) and other specialist system software. See also SSD1, DASD Fast Write.

Cache structure:  A Coupling Facility structure that contains data shared by systems in a sysplex.

Caching proxy server:  A proxy server that stores the documents that it has retrieved in a local cache. This allows for improved response times when these documents are subsequently requested.

CAD:  PS/2 drafting/design software. Supports bill of materials data, interfaces to CADAM, CATIA, and non-IBM systems. As it did with PC and Laser Printer, IBM appears to have hijacked a generic term and used it to refer to an IBM product. CAD/Plus had additional features. Both were withdrawn March 1993.

CAD/CAM:  Computer Aided Design/Computer Aided Manufacturing. What people used to call systems which control design and manufacturing systems (nowadays they tend to be called CIM). See 6090, Artic, CATIA, CAEDS, COPICS, DAE, MAPICS.

CADAM:  Computer Aided Design And Manufacture. At one time, an IBM product originally developed by Lockheed. Merged with CATIA and the CADAM name gradually disappeared. See CATIA.

CADAM Inc:  Lockheed software subsidiary acquired by IBM November 1989 for $80m as part of IBM’s drive into CIM, and renamed Altium in March 1993. Merged with IBM’s CATIA group a few years later.

CADD:  Computer Aided Drafting and Design. Generic term for software that automates drafting and design, notably of integrated circuits and printed circuit boards.

CAE:  Computer Aided Engineering.

CAEDS:  Computer Aided Engineering Design System. Integrated computer aided design system for engineers. Over the years, there have been versions that ran on the 5080 graphics system, z/OS, z/VM, RS/6000 under AIX, even the RT PC. In March 1994, they were all replaced by the I-DEAS Master Series from Structural Dynamics Research Corporation (SDRC).

CAF:  See Call Attach Facility.

Cairo:  A promised version of Windows NT based on distributed object technology, which was to be the successor to both NT 4.0 and Windows 95. Instead the operating systems remained divergent until Windows XP in 2001.

Call-AIX:  Remote support service for AIX and RS/6000.

Call Attach Facility:  Interface which enables application programs to access DB2 tables from outside the DB2 environment.

CallPath:  CallPath started life in mid 1989 as a way of linking Rolm 9750 voice exchanges with mainframe-based data applications, using a PS/2 to manage the protocol conversions between the data and the voice. Mid 1990, CallPath became CallPath Services Architecture (CSA) a generalized way of integrating a PABX with a computer system to allow application-initiated calls, call transfer, redirection of inbound calls, etc, and ultimately to allow the integration of voice with data applications. The first CSA product was CallPath/400 for AS/400. Later announcements included MVS/CICS, RS/6000, and PS/2 versions. In May 2001, IBM sold the CallPath product line to Alcatel.

CallUp:  On-line office directory application for VM (April 1992). Stores, maintains, and gives access to information about the people and services of an organization. Used to provide office directory support for OfficeVision/VM. Obsolete.

CALS:  Computer-aided Acquisition and Logistics Support. A US Department of Defense standard for exchange of electronic information. Mandatory after 1990 for weapons system documentation. Not surprisingly, IBM provides CALS products, mainly built around its SCRIPT text processor, which uses GML, which is the source of SGML, which is part of the CALS specification, which is the key to megasales of IBM equipment, which is recognized as a good thing by IBM. Support began in October 1989 with OS/2 and mainframe. Today, CATIA and ENOVIA are where you are most likely to see it.

CAM:  Computer-Aided Manufacturing.

CAMkit:  CADAM and Professional CADAM software for driving numerical control machines. Announced September 1991. CAMkit/370 was withdrawn August 1997. AIX CAMkit/6000 was withdrawn August 2001.

Capacity Backup:  Closely related to Capacity Upgrade on Demand (CUoD), CBU lets a small zSeries 900 be a backup for another system by expanding its capacity to meet emergency situations, such as hardware failure or disaster recovery. For example, an additional processor can be activated from the system’s reserve capacity. See also Geographically Dispersed Parallel Sysplex (GDPS).

Capacity on Demand:  Several IBM upgrade schemes for some iSeries 400 models. See Processor on Demand for one example. See also Capacity Upgrade on Demand.

Capacity Upgrade on Demand:  An IBM upgrade scheme that delivers eserver zSeries 900 systems with unused capacity so they can be upgraded when needed. An upgrade from a uniprocessor to a 10-way server is possible with no downtime. See also Vertical Capacity Upgrade on Demand, Horizontal Capacity Upgrade on Demand, Storage Capacity Upgrade on Demand.

Career Transition Program:  Ghastly IBM euphemism for a program to reduce its manpower by helping people to leave. Congratulations, we’ve decided to enroll you on our new Career Transition Program sounds so much nicer than Clear your desk, you’re fired.

Carrier:  An electric or electromagnetic wave that may be modulated to transmit information over a communication system.

CASE1:  Computer Aided Software Engineering. Generic term for systems designed to provide computer support for software development. Very fashionable at one time – although objects now command the attention of the dedicated follower of programming fashion. Typically, CASE systems support the analysts’ activities as well as programmers’, and involve sophisticated workstation graphics and advanced software engineering techniques. A distinction is sometimes made between upper CASE tools which support requirements and systems analysis, and design and data modeling, and lower CASE tools which support application generation. IBM failed to make an impact on this market, even with its most unequivocal endorsement of the CASE philosophy – the defunct AD/Cycle. See ADE1, WASE, MAESTRO, CAST.

Case2:  See Object.

CAST:  Computer Aided Software Testing.

Casters up:  Slang terminology for dysfunctional hardware.

Castors-up mode:  IBMspeak for broken.

Catalog:  A dataset that contains information about other datasets, e.g., type, location, size, format. The mainframe equivalent of the PC directory. The z/OS master catalog usually also contains entries for user catalogs. See also ICF2, CVOL, VTOC.

Category:  See security category.

CATIA:  Computer graphics Aided Three dimensional Interactive Application. Originally a CIM1 tool for design, drafting, solid modeling, numerical control; written by Dassault, and available from IBM as a package on mainframes and AIX boxes. Today, CATIA has absorbed the CADAM line and bills itself as the world’s leading CAD/CAM/CAE software. CATIA runs on Windows 9x/NT/2000, AIX, HP-UX, SGI IRIX and Sun Solaris. See also ENOVIA.

CATV:  CAble TeleVision. Wired, rather than wireless, reception of television, typically received off-air or via satellite at a central point then distributed, typically through an entire town or city, by coaxial and, more recently, fiber optical cable. Cable companies have traditionally operated as regulated monopolies, but that is changing, slowly.

CAU:  Controlled Access Unit. See 8230.

CAW:  Channel Address Word.

CBDS:  Circuit Board Design System. Graphics-based printed circuit design tool. Runs under VM and AIX. IBM withdrew from marketing the products after Valid Logic Systems and Cadence Design Systems merged under the Cadence name January 1992.

CBEMA:  Computer and Business Equipment Manufacturers’ Association. Renamed to Information Technology Industry Council (ITI) December 1994.

CBIPO:  Custom-Built Installation Process Offering. Package of system software together with a system for installing the relevant bits in the customer installation. One of IBM’s multitude of attempts to kill off the system programmer.

CBPDO:  Custom-Built Product Delivery Offering. IBM software distribution technique in which the user receives from IBM an incremental upgrade to an existing z/OS system. cf. CBIPO which is a complete system, not an upgrade.

CBT:  Computer-Based Training.

CBU:  See Capacity Backup.

CBX:  Computerized Branch eXchange. IBM/Rolm family of voice data exchanges (see 8750). CBX is also used in the US as a generic name for PABXs.

CC1:  Communications Controller.

CC2:  Control Code.

cc:Mail:  Lotus e-mail product which IBM took on (June 1991) as an alternative to the e-mail functionality of OfficeVision. Mid 1994 IBM stopped marketing cc:Mail when it brought out its AnyMail and UltiMail products, and then took it up again – via Lotus – when it bought Lotus.

CCA1:  Concurrent Communication Adapter. Facility on 3174 which provides concurrent host access. Became available end 1989.

CCA2:  See Common Cryptographic Architecture.

CCCA:  COBOL and CICS/VS Command-Level Conversion Aid. Tool to convert OS/VS COBOL, DOS/VS COBOL and ANSI 74 VS COBOL II into ANSI 85 VS COBOL II or IBM COBOL for OS/390 and VM. Runs in the z/OS and z/VM environments.

CCE:  Channel Control Element. The RISC processor boards that drove the channels in the 3090 and ES/9000.

CCHHR:  Cylinder-Head-Record. See CKD.

CCITT:  Comité Consultatif International de Téléphonie et de Télégraphie. International Telegraph and Telephone Consultative Committee. The CCITT used to be an element of the ITU (International Telecommunications Union). When the ITU was reorganized in March 1993, responsibility for standards was placed under the control of the ITU-T (ITU-Telecommunication Standardization Sector).

CCM1:  Concurrent Channel Maintenance. Feature, originally announced September 1991 for the 9021, which allows channels to be maintained without shutting down the whole CEC.

CCM2:  The CORBA Component Model, which (broadly speaking) generalizes EJB to multiple languages. CCM can be seen as a crystallization of best practice to date in building CORBA systems.

CCP:  Configuration Control Program. An IBM program used to define, display, and alter configurations that contain network controllers.

CCS1:  Common Communications Support. One of the pillars of SAA, CCS specifies the core communications functions and products for SAA-compatible systems. The original elements of CCS were those of SNA – later incarnations introduced new facilities or strategic directions mainly from outside the true-blue world; e.g., OSI was brought into CCS September 1988, ISDN in September 1991, TCP/IP and APPN in March 1992. Nowadays a discreet silence is maintained over the whole notion.

CCS2:  Console Communications Services. Feature of z/VM used by VCNA to communicate with z/VM routines.

CCSID:  Coded Character Set Identifier. Used to specify what national language character set is being used. For example, Japan Katakana extended range has a CCSID of 5026.

CCU:  Central Control Unit.

CCV:  Culture Compatible Vendor.

CCW:  Channel Command Word. An instruction to an I/O processor (channel). Performance-oriented Assembler programmers used to code their own CCWs because they thought the standard I/O macros generated inefficient CCWs.

CD:  Compact Disc. Can refer to a prerecorded music CD, CD-ROM, CD-R, CD-RW, or even a CD drive, recorder or player.

CDDI:  Copper Distributed Data Interface (also known as TPDDI – Twisted Pair Distributed Data Interface). A proposed copper wire version of FDDI. The idea is to use copper cable (UTP or STP) to support transmission rates up to 100Mb/sec – but only over very short distances (up to 100 meters). Strictly an interim solution to stave off a conversion to fiber optics.

CDE:  Common Desktop Environment. A desktop manager from the COSE initiative.

CDF:  Communications and Data Facility. The part of IBM’s CIM Architecture which provides data management services for CIM data. Consists of a DB2 repository and a data store. Used by IISR. Replaced by CDF/MVS.

CDF/MVS:  Common Data Facility MVS. February 1992 software which originally provided the communications and data management base for mainframe CIM systems. Built around DB2, and stores image, graphics, text, and data. Replaces CDF. Enhanced January 1993 with support for optical storage and binary large objects. IBM appeared at one time to be positioning it as a generalized, i.e., not just CIM, operational repository. An OS/2 GUI front end was announced mid 1993, and DataGuide, which is supported in CDF/MVS, was announced in October 1993. Withdrawn February 1996.

CDIF:  CASE Data Interchange Format. A generic sequential file interface specification for data models and related information.

CDIM:  Change Delivery and Implementation Manager. MVS software which delivers software, application programs, and data to multiple MVS systems allowing central control of large networks. Withdrawn February 1999.

CDLA:  Computer Dealers and Lessors Association. Has been renamed Information Technology Resellers Association (ITRA).

CDLI:  See Common Data Link Interface.

CDMF:  See Commercial Data Masking Facility.

CDPF:  Composed Document Printing Facility. Print driver for the 4250.

CD-R:  Compact Disk – Recordable. Exploits a specially designed recording layer in CD-R media, which undergoes a physical change at the spot where the high-power laser beam is focused to form a pit. The pits produced cause changes in reflectivity, and those changes are decoded to produce the 1s and 0s of the digital code stream. CD-R is based on WO technology.

CDRA:  Character Data Representation Architecture. IBM architecture (announced July 1990 and implemented in the 370/390 September 1990) which provides management of graphic character integrity across any pair of SAA database systems. See also GCD.

CDRM:  Cross Domain Resource Manager. SNA (VTAM) component for managing multi-domain SNA networks. Processes logons for other domains.

CD-ROM:  Compact Disk – Read Only Memory. Laser optical method of information retrieval from high capacity disk (normally 640MB). Initially defined by Philips and Sony in 1983, with their Yellow Book standard. This was later modified by the industry-wide High Sierra specification which defines the logical structure, file structure, and record structures of the CD-ROM disk. This served as the basis for the ISO 9660 international format standard for CD-ROM. See CD-RW, CD-R.

CDRSC:  Cross-Domain ReSourCe. A definition of cross domain resources (applications in other subareas of the SNA network).

CD-RW:  CD-ReWritable. A CD format developed jointly by Hewlett-Packard, Mitsubishi, Philips, Ricoh, Sony, and Verbatim which allows CD-RW disks to be written over repeatedly. Announced October 1996.

CDS:  Configuration DataSet.

CDSA:  Common Data Security Architecture. A framework set up between IBM, Security Dynamics, and RSA Security, aimed at establishing an open, multi-vendor environment for integrating and deploying security solutions for applications using the public key encryption methodology developed by RSA Security. Announced January 1998.

CDSM:  See Tivoli Cable Data Services Manager.

CDT:  See Class Descriptor Table.

CDU:  Coolant Distribution Unit. Box providing liquid cooling to the processor unit. Back in the days when processors had to be water-cooled or worse (Freon).

CEC:  Central Electronic Complex. IBMspeak for a group of processors which present a single system image to the users.

CED:  Compound (or possibly Comprehensive) Electronic Document. IBMspeak for something sent through an electronic mail system which either holds – or is capable of holding – a mix of data types. CEDs can hold information in a variety of formats – voice, data, image, text, high-resolution graphics, video, or a mixture of some or all of these.

CEDA:  A CICS transaction for on-line definition of CICS resources.

CEDF:  CICS Execution Diagnostic Facility. Testing aid from IBM.

Celeron:  A low end Pentium III processor introduced in 1999. Initially, virtually crippled, but later models were better than the Pentium III models of just six months earlier.

Cell relay:  A packet switching technology which uses standard sized packets over Broadband ISDN networks to simplify and speed up data transmission.

Cemetery:  IBMspeak for a bureaucratic non-job into which an older member of IBM staff has been shunted. There’s no way out other than retirement. See also Parking lot, Penalty box, Cooling house.

Center for On-Line Addition:  The first private, non-profit behavioral health care firm to specialize in Internet-related conditions. Does extensive research on the subject. Offers virtual clinics with on-line counseling through e-mail or chat rooms, as well as telephone counseling. Founded by Dr. Kimberly S. Young, Clinical Psychologist and Assistant Professor of Psychology at the University of Pittsburgh at Bradford (Pennsylvania, US). See Internet Addiction Disorder.

Central storage:  The storage which is directly linked to and accessible from the CPU. Used to be known as real or main storage. Does not include expanded storage.

CEPT:  European Conference of Postal and Telecommunications Administrations. In 1988, all standards work was transferred to the newly-created European Telecommunications Standards Institute (ETSI).

CERN:  Center Européen pour la Récherche Nucleaire, the European laboratory for particle physics near Geneva where the efforts of Tim Berners-Lee produced the World Wide Web and the first Web server.

Certificate:  See digital certificate.

Certificate-authority certificate:  RACF-managed digital certificate associated with a certification authority, used to verify signatures in other certificates.

Certificate Management Protocol:  Defines the interactions between PKI components. A certification authority (CA) is an example of a PKI component. Based on Internet standards RFC 2510 and 2511, which includes X.509 CRMF.

Certificate Name Filter:  In the SET architecture, a mapping of digital certificates to multiple user IDs created by RACF’s RACDCERT MAP command,

Certificate Request Message Format:  See CRMF.

Certificate Revocation List:  In the SET architecture, a list of digital certificates that are no longer valid. A certification authority (CA) makes the list available and keeps it current. But it only lists certificates issued by that CA. cf. Certificate Trust List.

Certificate store:  In the SET architecture, a storage location for digital certificates, Certificate Revocation Lists, and Certificate Trust Lists.

Certificate Trust List:  In the SET architecture, a predefined list of items that have been signed by a certification authority. The items need not be (just) digital certificates.

Certification:  See digital certificate.

Certification authority:  In the SET architecture, any trusted entity that follows established procedures when requested to issue a digital certificate by an individual, organization or machine.

CETI:  Continuously Executing Transfer Interface. Product which enabled the 9370 to talk with its integrated communications adapter at the physical and data link layers. In effect it was an alternative to VTAM for LAN attachment. Note that the user either had to re-write the operating and network software or use 4331/4361 emulation (supported by the CETI).

CF:  See Coupling Facility.

CFCC:  See Coupling Facility Control Code.

CF Channel:  The connection between a Coupling Facility (CF) and an operating system logical partition (LPAR). There are currently five types: Inter System Coupling link, HiPerLink, Integrated Cluster Bus link, Internal Channel link and Integrated Coupling Migration Facility link (ICMF).

CFO:  Customer Fulfillment Option. IBM procedure whereby direct account customers bought kit from dealers, but the IBM reps got the credits from the sales. The idea was to stop IBM competing too hard against its dealers.

C for VM/ESA:  C compiler for z/VM that supports Language Environment (LE) and OpenExtension. Announced October 1995.

CF Search/370:  VM Contextual Search/370. VM/CMS product enabling text search through CMS files based on full text indexing. A STAIRS basher. Withdrawn March 1991.

CFSizer:  See Coupling Facility Structure Sizer Tool.

CFSW:  An IBM software configurator accessible from IBMLink and HONE.

CGA:  Color Graphics Adapter. Original IBM PC color graphics standard. Offers 16-color palette with four colors simultaneously available in medium resolution (320 x 200 pixel), or 2 colors in high resolution (640 x 200 pixel). Succeeded by the EGA standard.

CGI:  Common Gateway Interface. A mechanism used by HTTP servers to invoke arbitrary programs for additional processing of certain requests: typically, those involving database access. While simple and convenient, CGI is now often replaced by ASPs, JSPs, or servlets when performance is important.

CGI Informatique:  A French computing services company which IBM acquired mid 1993. Quite why IBM wanted to buy a company with 4,000 employees at a time when it was laying off its own people in droves, is difficult to explain. The only likely reason seemed to be that IBM wanted to get its hands on CGI’s CASE expertise and products, notably Pacbase.

CGM:  Computer Graphics Metafile. A standard for defining vector (object-based) images, widely used in SGML-tagged documents. The preferred format for transferring two-dimensional drawings over the World Wide Web.

CHA:  CHAnnel driver card. I/O support card in the eserver zSeries 900 and previous System/390 systems. Introduced September 1996. See also FIBB.

Change management:  The methodology for planning and controlling software changes. This used to be more commonly known as the discipline of software management.

Channel:  A specialized computer used in the IBM mainframe architecture to control transfers between devices and the processor unit. The channel off-loads some of the processing associated with I/O from the main CPU. May 1993, mainframe channel emulation was announced for the RS/6000, allowing 3480/3490 and 3495 to be attached, presumably for distributed data management. Channel is also used to refer to the cable used to connect the channel processor to the peripherals. See Bus and tag, CTC, CTCA, Fiber optic channel, FICON, ESCON.

Channel adapter:  Hardware unit to attach a channel to a processor.

Channel attached:  Devices that are directly attached to the processor by cable rather than over a communications link.

Channel extender:  Device for extending the distance over which devices can be attached to a processor channel. IBM’s preference is to use FEPs for this (although see 2944, 3737), but independent vendor products (Hyperchannel, Paradyne, CNT, Comparex) often did the same job better and/or cheaper. The need for channel extenders was reduced (although not eliminated) by the introduction of the ESCON channel architecture. The 9036 allows the channel to be connected across a PTT network.

CHANNELink:  Remote channel connection system from Computer Network Technology for connecting devices to mainframes across a WAN. Used in 3990-6 Extended Remote copy.

Channel link:  An I/O channel-to-control unit interface found on mainframes that have an SNA network address. A channel link can be a subarea link, a peripheral link, a LEN link, or an APPN link.

Channel router:  Generic term for a device which acts as a multiway switch between a processor and device. The ESCON director is such a beast.

Channel Subsystem Priority Queuing:  New with z/OS, WLM now prioritizes channel I/O requests across all LPARs.

Checksum:  A mathematical calculation made on data in a file, database or transmission, used to check the integrity of the data.

Chestnut:  IBM code name for DAE.

Chicago:  The code name for what became Windows 95.

CHPID:  CHannel Path IDentifier. A single byte binary value used to uniquely identify each channel path on an eserver zSeries 900 and previous mainframe systems.

CHRP:  Power Reference Platform. An IBM standard architecture for systems built using the PowerPC chip. Appears to be much the same as PReP. See PowerPC Platform.

CI:  Command Interface. Interface between CLISTs and QMF – the interface enables CLISTs to make use of QMF services.

CIB:  Control Information Base. IBM term for a type of Management Information Base (MIB) which contains control information – short-lived, requiring a prompt response, and of limited applicability. The CIB is quite likely to be on a distributed node in a network. cf. EIB.

CICS:  Customer Information Control System (although these days IBM tends to say that it stands for Certainly Is Client/Server, or, for the stomach-churning Continually Increasing Customer Satisfaction). General purpose TP monitor for terminal-oriented and inter-system transaction processing in z/OS and VSE/ESA environments. Sits between user application programs, teleprocessing access method (e.g., VTAM), and database managers – i.e., CICS invokes user-written application programs in response to transactions entered at TP terminals. Originally developed for (the predecessors of) z/OS and VSE/ESA, but has evolved into a client/server product, in a number of ways. There are several non-mainframe versions, but only CICS Transaction Server for iSeries and OS/2 are still available. The CICS Transaction Gateway interfaces CICS on z/OS with clients on a broad range of platforms. And, for a time, there was the TXSeries, which merged CICS, Encina and IBM Transaction Server.

CICS/400:  AS/400 version of CICS first announced in February 1992 as Version 2.2. Renamed CICS Transaction Server for iSeries.

CICS/6000:  Written in C by IBM using TP technology from Transarc, and incorporated the Encina software. Replaced by Transaction Server for AIX in January 1997, which was withdrawn December 1998. See CICS.

CICS/AMA:  CICS Application Migration Aid. IBM program designed to help people convert their COBOL programs from CICS macro-level to command-level. Originally available as a licensed program and as a remote service. No longer supported December 2001.

CICS/AO:  See CICS Automation Option.


CICS/CMS:  VM product for developing CICS command-level applications in a VM/CMS environment. Replaced by CICS/VM April 1989.

CICS/ESA:  Release of CICS announced July 1989 on CICS’ 20th birthday. Claimed to offer lots of enhancements in reliability, serviceability, and performance (particularly a reduction in the resource requirements of CICS own monitor), and to address 200 user requirements initiated from groups such as GUIDE and SHARE. It was a major re-write (using the Z technique) which stripped out a lot of redundant code, and made CICS leaner and fitter than it had been for years. It’s also OCO, and finally did away with macro-level programming, whose demise has been the cause of many a tear among CICS buffs. Replaced by CICS Transaction Server for z/OS. See also CICS.

CICS/MVS:  Version 2 of CICS in February 1987 which gave a degree of fault tolerance (filched from the IMS XRF), and interfaces to C. Replaced by CICS/ESA, but supported for many years because it was the last version of CICS that supported macro-level programming. Withdrawn April 1994, with support ending December 1996.

CICS/Unix:  A version of CICS/6000 which IBM sold to the open Unix market – i.e., to run on other vendors’ platforms. Obsolete.

CICS/VM:  Version of CICS which ran under VM/IS on the 9370. Designed for applications where seamless integration is more important than high performance, which is a polite way of saying that it ran with great dignity – but slowly. In fact it was a non-starter for production applications – just a development and testing environment. Replaced CICS/CMS and was itself withdrawn December 1992.

CICS/VSE:  September 1990 version of CICS for VSE/ESA users. Offered functional, RAS and performance enhancements over previous versions. Replaced by CICS Transaction Server for VSE/ESA.


CICSAO:  See CICS Automation Option.

CICS Attach:  Generic name for software within a database system (IBM or third-party) which enables the DBMS to support CICS applications.

CICS Automation Option:  July 1991 MVS NetView application which automates CICS functions from a single point of control. Can be used to drive multiple local or remote CICS regions by automating functions such as start-up, shut-down, and recovery. Replaced by the CICS Auto Feature of AOC/MVS.

CICS Clients:  Replaced by CICS Transaction Gateway and CICS Universal Clients.

CICS Connector for CICS TS:  Part of CICS Transaction Server for z/OS. Enables Java enterprise beans to invoke non-Java programs using code that can be generated automatically by VisualAge for Java.

CICS External Call Interface:  An API that allows a non-CICS client program to call a CICS program.

CICS External Presentation Interface:  An API that allows a non-CICS client program to appear to CICS as if the program is a 3270 terminal, thereby eliminating the need to change existing CICS applications.

CICS for AIX:  Obsolete. See CICS.

CICS for OS/2:  System (announced October 1988) for running small TP-type systems on a PS/2 or PC/AT – i.e., it allows a PC to be used as a CICS transaction server on a LAN. Supports an application-oriented subset of the COBOL CICS command-level API, and includes LU6.2 support. Available in client and server (CICS OS/2 Multiuser) form. Renamed CICS Transaction Server for OS/2. See CICS.

CICS for Windows NT:  Obsolete. See CICS.

CICS Fundamentals for e-business:  Not a piece of software, but an HTML-based self-study course that describes the main concepts and facilities of CICS and the most commonly used CICS transactions.

CICS Gateway for Java:  Originally shipped as a component of Version 1.2 of CICS Transaction Server of OS/390. Replaced by the CICS Transaction Gateway.

CICS Internet Gateway:  Replaced by the CICS Transaction Gateway.

CICS Monitoring Facility:  Creates SMF type 110 records with data about the performance of all user- and CICS-supplied transactions. See also CICS Performance Analyzer.

CICS ONC RPC:  See CICS Open Network Computing Remote Procedure Call.

CICS Open Network Computing Remote Procedure Call:  Allows non-CICS applications to access CICS-managed data.

CICS OS/2 Multiuser:  Version 2 of CICS for OS/2, announced March 1993. Turns a PS/2 into a full blown TP server. IBM sold it both for systems downsized from the mainframe, and systems upsized from LANs. Renamed CICS Transaction Server for OS/2. See CICS.

CICS PA:  See CICS Performance Analyzer.

CICSPARS:  CICS performance monitor. Collects information about such things as transaction rates, response times, paging rates, virtual/real storage use. There were separate versions for MVS and VSE environments. Withdrawn February 1991.

CICS PD/MVS:  CICS Problem Determination/MVS. Set of tools, announced September 1990, for the diagnosis and resolution of CICS region failures in CICS/ESA. March 1993, IBM sold the marketing rights for PD/MVS to Compuware Corporation (which originally developed the system in 1989).

CICS Performance Analyzer:  A z/OS product that analyzes the SMF records created by the CICS Monitoring Facility (CMF), creating reports and extracts useful for tuning and system management. Announced May 2001.

CICSplex:  A single system formed by interconnecting multiple CICS systems (originally using MRO), to form a single system image (see SSI1).

CICSplex SM:  See CICSplex System Manager.

CICSplex System Manager:  February 1994 system management product, initially for CICS/ESA, (bought in from Boole & Babbage Inc) which enables all of the CICSplex systems in a network to be managed as a single system image (see SSI1) without the operator having to know where the component systems are located. Designed for use by systems programmers, systems administrators, and master terminal operators. Web User Interface announced November 1999. Pre-requisite for the Parallel Transaction Server.

CICS Transaction Affinities Utility:  z/OS software introduced in February 1994 which identifies transactions requiring two programs to share the same application owning region. No longer supported after December 2001. See also CICSplex.

CICS Transaction Gateway:  A multi-user CICS gateway which supports programming interfaces on the same (middle) tier as the Web application server, for use by Web applications in Java and other languages. CTG runs on z/OS, Linux/390, AIX, Windows NT/2000, Sun Solaris and HP-UX. See also CICS Universal Clients.

CICS Transaction Server for iSeries:  See CICS.

CICS Transaction Server for OS/2:  See CICS.

CICS Transaction Server for VSE/ESA:  A packaging of CICS and some products that had been sold separately. Includes CICS Web Support, REXX for CICS, CICS Universal Client and the CICS Transaction Gateway function. Announced September 2000. See also CICS.

CICS Transaction Server for z/OS:  IBM repackaging of CICS for z/OS (November 1996), replacing CICS/ESA version 5. Version 1 was intended primarily to exploit the Parallel Sysplex – a Coupling Facility is a prerequisite. Includes server, client, and management functions, and facilities such as VSAM data sharing, shared temporary storage, and resource definition for transient data. Version 2 announced September 1997. See also CICS.

CICS TS:  See CICS Transaction Server for z/OS and CICS Transaction Server for VSE/ESA.

CICS Universal Clients:  Part of IBM’s Application Mining initiative. Provides access to any CICS platform from a single workstation user running Windows, OS/2, AIX and Solaris. CICS Transaction Gateway is intended for multi-user applications. CICS Universal Clients was withdrawn December 2002 with functionality included in other products, most notably CICS Transaction Gateway.

CICSVR:  CICS VSAM Recovery. Software providing forward recovery of VSAM datasets. A utility is invoked each time a CICS journal is archived, which reads the CICS journal and stores information in the CICSVR recovery control dataset (RCDS), which is used for recovery. The recovery can be carried out on a system where CICS is not installed so that the CICS service can be continued in parallel with the recovery.

CICS VSAM Recovery:  See CICSVR.

CICS Web 3270 Bridge:  See 3270 Bridge.

CICS Web Interface:  Originally, a free CICS feature that provides direct access to CICS from a Web browser. Announced September 1996. Later became a part of CICS Web Support.

CICS Web Support:  HTML protocol support within CICS.

CID:  Configuration, Installation, and Distribution. IBMspeak for the information/functions needed to manage distributed workstations.

CIEDS:  Computer-Integrated Electrical Design Series. Mainframe, PC, AIX software. Replaced by CBDS December 1990.

CIM1:  Computer Integrated Manufacturing. Generic term for systems used to control manufacturing processes. CIM tools include MRP, CAD/CAM, inventory control, just-in-time scheduling, etc. IBM CIM products include Artic, CATIA, CAEDS, CIM Advantage, COPICS, DAE, Gearbox, and MAPICS (with over 65,000 licenses). See also CATIA, ENOVIA.

CIM2:  Common Information Model. See DMTF.

CIM Advantage:  IBM family of CIM products announced October 1989. Also goes under the name Industrial Solutions. Withdrawn December 1993. See also CATIA, ENOVIA.

CIMAPPS:  CIM Advantage Production Planning Series. MVS and VSE CIM software derived from COPICS for the SQL environment. Withdrawn December 1993. See also CATIA, ENOVIA.

CIM Architecture:  Yet another architecture. CIM Architecture (announced October 1989) was based on SAA and AIX platforms, and included various bits of software which, according to IBM, all talk to one another. Frankly, it was all rather vague, and seems to have fallen into disuse. See also CATIA, ENOVIA.

CIM Series/400:  Suite of CIM products for the AS/400. Announced September 1990. Provides a building block approach for integrating various systems – including RS/6000 CAD, OS/2 CAD, MAPICS. Withdrawn April 1995. See also CATIA, ENOVIA.

CIO:  Channel Input and Output.

CIP1:  Cisco’s Channel Interface Processor that permits a Cisco 7000/7500 class bridge/router to be ESCON or bus-and-tag attached to a mainframe. And can optionally act as a tn3270 server.

CIP2:  Controlled Introduction Program.

Cipher text:  A message that has been encrypted. See also encryption.

Circuit-level gateway:  In a firewall1, a proxy server that redirects a client’s request through the firewall to the intended server. cf. application-level gateway.

CISC:  Complex Instruction Set Computer. The opposite of a RISC. The Intel chips used in the PC and PS/2 are typical CISCs, as is the processor in IBM mainframes and the Motorola 68000.

CIT:  Computer Telephony Integration. See CTI, CST.

Citrix MetaFrame:  Provides support within AIX for high bandwidth X.11 and Java applications over thin connections.

CKD:  Count Key Data. The original way that disk drives were formatted on mainframes. CCHHR would locate a record on disk by cylinder number (CC), track number within the cylinder (HH for head number) and physical record (block) number within the track (R). cf. FBA.

Class:  A collection of RACF-defined entities with similar characteristics.

Class Authority:  A user attribute specifying the classes, if any, where the user may create RACF profiles.

Class Descriptor Table:  A RACF table containing entries for each class, except USER, GROUP and DATASET.

Classic Connect:  SQL read-only access to IMS databases and VSAM datasets. A middleware server than runs on z/OS and provides access from other platforms. Announced April 1999, replacing DataJoiner Classic Connect.

CLAUTH attribute:  See class authority.

CLAW:  See Common Link Access for Workstations.

Clear data:  In cryptography, data that is not enciphered.

Clever:  The code name for an algorithm developed at the IBM Amalden Research Laboratories for refining the search ability of search engines.

CLI1:  Call Level Interface.

CLI2:  Calling line identification. Within telephony systems, the mechanism which enables the called telephone to know the caller’s number.

Client/server:  Generic term for systems (also known as server/requester) in which one machine provides a range of services to one or more other machines. Typically, intelligent workstations (clients – also known as requesters) share access to one or more other machines (servers) which provide services to the workstations. Services may include printing, filing, processing, database access, etc. These days the server and the client both tend to be intelligent (except for print servers), to be transparent to the user, and to work cooperatively using program-to-program communication. Note that in the context of X-Windows, the terms have exactly opposite meanings; an X-Windows server is the user’s terminal, and an X-Windows client is the computer to which the server terminal is connected. See also Cooperative processing.

Client Access:  A family of products providing access to iSeries 400, originally a mid-1990s replacement of PC Support. Client Access Express for Windows provides TCP/IP connectivity for Windows workstations, including 5250 emulation, DB2 data transfer and access to the OS/400 Integrated File System (IFS) and printers. iSeries Access for Web provides a subset of these functions for Web browser users.

Client Access Express:  Part of the Client Access family of products.

Client daemon:  A process in AIX that performs a client’s operations.

CLIST:  Control language used to manage interactive applications in the z/OS TSO environment. Largely superseded by REXX, which SAA brought from VM as the procedure language standard. Also used generically to refer to any set of control language statements which can be called by name.

Clone:  More or less synonymous with PCM machine. Originally referred to non-IBM replicas of the IBM PC.

Closed:  Usually a reference to a proprietary system that therefore cannot readily be connected to other systems. cf. Open.

Cloud 9 for SCLM for z/OS:  A browser-based centralized Software Configuration Management (SCM) tool for developing and deploying z/OS-based e-business applications containing objects such as HTML files, Java programs, z/OS objects, Web applications, documents and spreadsheets stored on various platforms. See also SCLM.

CLPA:  Create Link Pack Area. An option used during IPL to initialize the Link Pack Area (LPA).

Cluster1:  A group of devices comprising a cluster controller and one or more devices.

Cluster2:  A VSAM structure comprising a group of related components.

Cluster3:  A measure of space on a PC diskette. PC-DOS allocates space to files in cluster increments.

Cluster4:  An architecture, employing hardware, software, or both, in which multiple computers behave as one. Parallel sysplex is a good example. Technically, even one computer becomes a cluster when all the parallel sysplex pieces are put into place. And this is typically how most parallel sysplexes begin, just to test the technology in a production environment, in preparation for the real thing. Clusters have several advantages, particularly in regard of reliability and ease of upgrade.

Cluster controller:  A device that can control the I/O operations of multiple devices. A cluster controller can be controlled by either software, such as the 3601, or hardware, such as the 3272. Now known as Establishment controller.

Clustered FORTRAN:  Version of FORTRAN announced with Supercomputing Systems Extensions (see SCSE). Enables up to 24 processors (in up to four 3090s or ES/9000s) to be linked together via a 4GB common memory to execute a single application. Also supports the PIOAM and File striping. Obsolete.

Cluster Management Utility:  OS/400 software that allows you to create and manage a simple two-node, switched disk cluster. The utility includes wizards and help text that simplify the tasks involved in defining and managing the cluster.

ClusterProven:  IBM certification for a combination of application software and IBM server cluster that has passed a test for total system availability, scalability and resiliency characteristics. A year after being introduced in 1999, 60 applications from 40 different vendors had passed the test, including IBM, of course. See also Advanced ClusterProven.

Cluster System Management:  AIX’s support for management from a single point of control, monitoring, running commands and collecting output across a domain of AIX machines.

CM:  See Communications Manager.

CMC:  Communications Management Configuration. IBM method of concentrating all of the network management functions onto one processor (sometimes also known as the CMP – Communications Management Processor) in a multi-host SNA network. The CMC host does no work other than managing the network, while the other hosts perform no network management. Never very popular.

CMF:  See CICS Monitoring Facility.

CMIP1:  Common Management Information Protocol. OSI standard for network management data which should enable different network management systems to exchange information. Although it was designed for OSI networks, CMIP is transport independent, and there is no reason why CMIP shouldn’t be used directly on SNA networks. CMIP is supported in IBM’s OSI/CS product, and in September 1991, IBM announced that it would support CMIP across a wide variety of networking environments. See also CMOL, CMOT, CMIS, HLM, SNMP.

CMIP2:  IBM Content Manager ImagePlus for z/OS. See ImagePlus.

CMIS:  Common Management Information Service. The interface used by applications to access OSI network management functions. Uses the CMIP1 protocol.

CMOL:  CMIP1 over LLC. 3Com/IBM protocol for the use of the CMIP network management protocol over LLC-based Ethernet and Token Ring networks. Never really took off.

CMOS:  Complementary Metal Oxide Semiconductor. A chip technology used almost universally for processors today. Mainframes were the last to move to CMOS because, until the mid-1990s, bi-polar technology, though much more expensive, was the only way to make a single processor fast enough to handle many batch workloads in large organizations. As well as cost, CMOS also eliminated the need for water-cooling that larger bi-polar processors required.

CMOS copper technology:  See copper.

CMOS Cryptographic Coprocessor:  Encryption hardware that is included with the eserver zSeries 900. See also PCI Cryptographic Coprocessor.

CMOT:  CMIP1 over TCP/IP. IETF standard supporting the use of the CMIP management protocols over TCP/IP networks. Published April 1989 as RFC 1095.

CMP1:  Cooperative Marketing Program. A quick and dirty method for IBM to market third-party software without having to get tangled up in lengthy agreements.

CMP2:  Communications Management Processor. The processor in a CMC.

CMP3:  See Certificate Management Protocol.

CMS1:  Conversational (originally Cambridge – the lab where it was built) Monitor System. Operating system running under VM, and providing timesharing and program development facilities. Comparable in function to TSO but less resource hungry and generally friendlier. Main use is for software development, and latterly for end-user Information Center support. The original file system was mainly oriented towards small files which made it a non-starter for critical applications.

CMS2:  Cross Memory Services. MVS extension to the basic mainframe architecture which uses DASF to simplify sharing data between address spaces. CMS is a way of circumventing the 5MB private area limitation of MVS. Used extensively in the distributed version of DB2. Also known as XMS.

CMS3:  Custom Migration Support.

CMSDESK:  CMS Desktop. A GUI providing a subset of CMS functionality on a z/VM host from a Windows, OS/2 or AIX workstation.

CMS Pipelines:  CMS job control product for z/VM that enables complex tasks to be specified and executed. CMS Pipelines has three parts – a command parser, a library of built-in programs, and a dispatcher.

CMVC:  Configuration Management and Version Control. Development tool for OS/2, and RS/6000 and other Unix platforms, announced January 1992. Provides configuration management, version control, integrated problem tracking, and notification and reporting. Replaced by VisualAge TeamConnection Enterprise Server October 1999.

CNAT1:  Central Node Administration Tool. z/OS ISPF application (announced July 1989) for running distributed VSE/ESA systems. Includes facilities for generating and submitting jobs to VSE/ESA nodes, and for central management of software. Withdrawn March 1993.

CNAT2:  See Tivoli Comprehensive Network Address Translator.

CNM:  Communications Network Management. Interfaces and entities (e.g., programs such as NPDA, RTM1, NPA) of SNA’s network management architecture.

CNMI:  Communications Network Management Interface. VTAM interface allowing an NCCF command processor to request and receive network management information from the network.

CNN:  Composite Network Node. A node in an SNA network which includes a VTAM (host) node and all of the NCP nodes within its domain. To an APPN network, a composite node appears as a single APPN network node.

COACH:  COgnitive Adaptive Computer Help. A system which is included as a standard part of IBM’s OS/2 Warp operating system, called WarpGuide. It models user behavior and uses an inference engine to provide proactive and adaptive assistance. COACH has been applied to both application-specific environments and general-purpose system interfaces.

COAR:  Computer Output Archival and Retrieval. A possible replacement for COLD technology. COAR is more representative of the current archival and search and retrieve technologies, which will add more value and broad accessibility to applications based on computer output. See COLD, COM.

Coax:  Coaxial cable. The standard medium (like a bloated version of TV aerial cable) for connecting mainframe (3270 family) terminals. Although coax is capable of carrying lots of information, it’s the bane of many a DP manager’s life – it’s fat, inflexible, and incompatible with telephone wiring. The IBM Cabling System, which can use standard telephone twisted pair wires, marked the start of the end for coax.

COBOL:  Widely-used programming language for commercial applications. SAA-anointed in the ANS X3.23 (1985 Intermediate Level) version. COBOL has always been the most popular programming language on the IBM mainframe, from System/360 to eserver zSeries 900. For more than 20 years, the popular mainframe compilers have been DOS/VS COBOL, OS/VS COBOL, VS COBOL II and IBM COBOL. IBM COBOL runs on z/OS, z/VM and VSE/ESA. IBM ILE COBOL runs on OS/400 and VisualAge for COBOL on Windows. And there is COBOL Set for AIX.

COBOL/2:  SAA-anointed Version of COBOL for the workstation (OS/2). Originally developed by Micro Focus, but marketed by IBM. Obsolete.

COBOL/SF:  COBOL Structuring Facility. z/VM and z/OS software which uses expert systems to turn tacky old COBOL programs into paragons of structure. Includes complexity metrics, and code restructuring. Withdrawn March 2001.

COBOL Productivity Suite:  Integrated set of host and workstation tools that help improve programmer productivity. Withdrawn June 1996.

COBOL Set for AIX:  COBOL application development environment for AIX1 with object-oriented and client/server support. See also COBOL.

COBOL VisualSet for OS/2:  See VisualSet.

COBTEST:  COBOL test tool. Replaces TESTCOB. Obsolete.

Codasyl:  Conference On Data Systems Languages. A standard for database systems (strictly it’s the committee which maintains the standard). IBM does not itself provide a Codasyl database – the only Codasyl database available for the IBM mainframe sector is IDMS.

CODE/370:  CoOperative Development Environment for System/370. Mainframe/workstation software, announced September 1991, which provides combined edit, compile, and debug facilities for high-level (initially COBOL and C) languages to create applications for the z/OS and z/VM environments. Uses cooperative processing techniques, with an OS/2 front-end talking to a host mainframe. The workstation portion was replaced by VisualAge and C/C++ Productivity Tools in February 2000. The host Debug Tool is still available.

CODE/400:  CoOperative Development Environment for iSeries 400. Workstation software, announced mid 1991, which provides combined edit, compile, and debug facilities to create applications for the iSeries 400. Initially, it only supported RPG, but has since been expanded to COBOL, C, C++, DDS, CL (Control Language) and Java. Uses cooperative processing techniques, with a workstation front-end, initially OS/2, now only Windows, talking to a host iSeries 400. Became a part of ADTS (Application Development Toolset) in June 1995. In turn, ADTS became part of WebSphere Development Studio for iSeries in July 2001.

CODEC:  COmpression-DECompression. Adapters that compress and decompress audio/video files. Used to stand for COder-DECoder.

Coexistence:  In z/OS, the ability of up to four consecutive releases of the operating system to run on a multisystem configuration.

Coign:  Part of Microsoft’s Millennium research project, which analyses application code (both statically and dynamically) and decides how best to partition it to optimize performance.

COLA:  See Center for On-Line Addition.

COLD:  Computer Output to Laser Disk. Early systems often used optical disks (or laser disks) as the archival media. Current optical technology, however, offers CD-ROM-based archival subsystems, RAID subsystems, various optical disk jukeboxes or autochanger systems, and others – with an assortment of software for their use. See COM, COAR.

COM:  Component Object Model. Microsoft’s rules and architecture for software objects. See also COM+, DCOM.

COM+:  An improved version of COM, incorporating the functionality of MTS1 and providing sophisticated runtime services.

Com300:  IBM branding of the Siemens Hicom300 digital PABX; at one time available in Germany, Luxembourg, Belgium, the UK, and other countries where the local PTT allowed IBM to sell it. Replaced the 1750 and 3750. Defunct.

Comb:  An assembly of access arms in a magnetic disk unit that move as a unit.

Command Direction:  RRSF’s ability for users to issue a command and specify it be run on a local or remote RACF, on their own or another user ID.

Command interpreter:  A program in AIX that sends instructions to the kernel.

Command-level:  A method of CICS application programming that provides a much simpler method of programming than the macro-level CICS programming which it replaced.

Command operator:  A special character in OS/2 or DOS, used to redirect input or output, or for conditional processing or grouping.

CommercePOINT:  A suite of payment programs for Internet commerce. Using the SET security procedures, CommercePOINT Wallet allows use of credit/debit cards through PCs. CommercePOINT Till is the electronic cash register for vendors. CommercePOINT Gateway allows connection between banks/credit card providers and merchant sites. Became the Payment Gateway for OS/390 mid 1998.

Commercial Data Masking Facility:  Part of the IBM Common Cryptographic Architecture. 40-bit encryption used by RACF to mask the data portion of RRSF transaction processing message packets.

Commit:  The point in a TP system at which a transaction actually takes place. In an industrial strength TP system, such as CICS, the commit only takes place when the system is sure that all data so far processed is recoverable in the event of a system failure. On-line programs typically commit automatically at the end of a transaction. For batch programs, the programmer typically initiates the commit at regular intervals during processing.

Commodity:  Commodity items in the computer industry are those sold on a lowest bid wins basis with none of the value-adds beloved of IBM. PC compatibles and clones are typically sold as commodity items. In the past, IBM had always steered clear of commodity markets, but increasingly was dragged into them as the computer industry matured. With the exception of the iSeries 400, virtually all IBM hardware is now sold into what are effectively commodity markets.

COMMON:  International user group for users of mid-range IBM systems.

Common Area:  Area within the z/OS operating system containing the z/OS code itself, plus key z/OS data (e.g., control blocks). Shared by all users.

Common Cryptographic Architecture:  September 1990 vintage architecture which provides a standard cryptographic API for z/OS and VSE/ESA applications. Implemented in the Integrated Cryptographic Feature.

Common Data Link Interface:  Allows snmpd to monitor Ethernet, Token Ring and FDDI devices even if they are not running TCP/IP. Supported by AIX1.

Common Data Security Architecture:  See CDSA.

Common Link Access for Workstations:  The IBM Layer 2 channel-protocol used by IBM on the 3172 and Cisco on the CIP to transport TCP/IP traffic across bus-and-tag or ESCON II channels.

Common LISP:  IBM environment – comprising mainframe and PC or PS/2 software – for developing and running LISP programs. Developed and jointly marketed by IBM and Lucid Inc. IBM withdrew from the joint marketing agreement in March 1990.

CommonPoint:  The first deliverable – an object-oriented application development system/environment for OS/2 and AIX. From the Taligent company. Withdrawn December 1997.

Common Process Manager:  See ADPS.

Common Queue Server:  Used by IMS and other software for Shared Message Queuing with the Sysplex Coupling Facility.

CommonStore:  See Content Manager.

Communications Manager:  The bit of OS/2 that – surprise, surprise – manages communications. Supports lots of protocols, including asynchronous, SNA LU0, X.25, Ethernet, IEEE 802.3, and also provides an SNA LAN gateway. Available only as part of the OS/2 EE bundle until early 1991, when it became available separately. Includes support for APPN, host NetView, CPI-C, and enhanced NDIS. Withdrawn July 1994.

Communications Server:  IBM software that supports several APIs that may be called concurrently and that are designed for client/server and distributed application programs. Available on AIX1, OS/2, z/OS, and Windows NT/2000. An SCO UnixWare version was withdrawn March 2001. The z/OS version includes VTAM and is an optional, separately priced element of z/OS. This implies full integration testing with z/OS and all its other elements.

Communications Server for MVS/ESA:  Multiprotocol networking solution from IBM (Nov 1996), which includes VTAM 4.3, TCP/IP 3.2, and AnyNet. Intriguingly, it’s aimed at users who don’t intend to go to OS/390. Withdrawn March 2000.

Communications Suite for Windows:  See eNetwork Communications Suite for Windows.

Communique:  Group of vendors, headed by HP and IBM, which at one time was developing the Broadcast Message Server (BMS) CASE standard. Not a lot is heard from it these days.

Compaction:  Within DFSMShsm, a method used for compression and encoding of data during migration or backup to reduce required storage space.

Compile:  The translation of a high-level programming language (source program) into a machine language program (an executable program). Some operating systems, including z/OS, z/VM and VSE/ESA, require an additional step before the program can be actually executed; see Program Management Binder for the z/OS and z/VM requirement.

Compiler:  A program that translates high-level programming languages into machine language programs.

Compiler for REXX/370:  A compiler for the normally interpretive REXX language, available for z/OS and z/VM. Intended to speed up large REXX applications.

Component Broker:  Originally known by its code name of BOSS. It is a super middleware framework from IBM. A component-based application development strategy with common tool interfaces with which IBM intends to promote its object oriented technologies such as SOM/DSOM and Bighorn server software. Now part of WebSphere Application Server, Enterprise Edition.

Componentization:  Customizing an applet’s functionality to match the needs of a specific set of users, to eliminate the downloading of unnecessary code to the client. This cuts down applet download times.

Composer:  See DisplayWrite Composer.

Compression:  Generic term for a method of reducing the amount of space needed to store data, by encoding the data. This is achieved through the elimination of empty fields, gaps, redundancies, and unnecessary data to shorten the length of records or blocks. Also used specifically by IBM to refer to the technique of removing embedded, unused space from between members of a partitioned dataset. A compression TCM1 (which requires special versions of the appropriate software, including MVS/ESA 4.3) was introduced into the ES/9000 in February 1993. See also Compaction, IDRC.

COMTI:  Microsoft’s COM-based Transaction Integration. An extension to Microsoft Transaction Server (MTS) to enable it to support CICS, IMS, DB2 and 3270/5250 transactions.

Concurrent Channel Maintenance:  First introduced as an optional feature on the Summit ES/9000s which allows a failing channel to be repaired or replaced without interrupting processor operation.

Conditional Access List:  RACF users and groups permitted access only when a specified condition is true. For example, access to a dataset may be permitted only when executing a specific program.

Confidential mailbox:  An option available on the IBM Network Printer 17 that ensures confidential print jobs are output into a locked security box which can be accessed only by inputting a PIN to the printer. The Network Printer 17 has 10 of these secure bins, which can hold a maximum of 40 sheets each.

Connect for iSeries:  B2B software integration framework using Java, XML and the Internet to connect an organization’s application software with its trading partners. Supports Domino, WebSphere and MQSeries.

Connectionless communication:  A type of communication in which there is no formally established physical communication path between the two communicators; i.e., there is no notion of a set-up and take-down phase at the start and finish of the connection. Packet switching, datagrams, store and forward, and asynchronous delivery services such as SNADS, are examples of connectionless communications.

Consent decree:  A voluntary agreement entered into by a US company to avoid Uncle Sam clobbering it under anti-trust legislation. IBM has entered into various consent agreements (notably one in 1956) covering such topics as unbundling, and selling as well as renting its hardware. By 1994, IBM’s market dominance had eroded to the extent that it launched an appeal against the 1956 consent decree, and after forty years and nine months IBM finally extracted itself from the decree in May 1997.

Consumer Transaction Facilities:  IBM’s verbally succinct terminology for hole-in-the-wall machines. See also 1/LINK, 3624, ATM1.

Content Connection:  Replaced by Content Manager.

Content Manager:  A portfolio (product family) providing an enterprise content management infrastructure for e-business information. Supports z/OS, iSeries 400, AIX1, HP-UX, Sun Solaris and Windows NT/2000. Includes ImagePlus, OnDemand and VideoCharger components, as well as CommonStore components for Domino and SAP2. Replaces Content Connection, Digital Library, EDMSuite and FAF.

Content policy:  Rules within an organization regarding what type of material may not be stored on computers, such as pornography.

Content security:  Enforcement of content policy.

Contingency planning:  Any cost-effective preparations for negative future circumstances.

Control block:  Areas of storage within mainframe system software much loved of systems programmers. Control blocks contain data used to control part of a system or subsystem – system parameters, addresses, pointers, counters, etc.

Controller:  Specialized processor which sits between a channel and one or more peripherals. IBM controllers include the 3880 and 3990 disk controllers, the 3725 and 3745 communications controllers (FEPs), and the 3274 and 3174 cluster controllers.

Control point:  A program which manages an APPN network node and its resources, enabling communication to other control points in the network.

Conversation:  The logical connection between two programs serially sharing an LU6.2 session.

Convertible:  IBM laptop PC which claimed to be a member of the PS/2 family but was nothing more than a physically small PC. Didn’t do very well in the market and ended up being sold off as a special offer in high street hi-fi shops. Obsolete.

Cookie1:  IBMspeak for the recording medium of a diskette, i.e., the spinning disk inside the jacket.

Cookie2:  User preferences and data that the user may submit while browsing the site that a Web server stores as a small file on a user’s computer when the user browses a particular Web site. The use of cookies enhances Web site interactivity on future visits. But they are the subject of considerable debate among security and consumer groups as to their ability to tie together (for marketers) otherwise disparate pieces of information about individuals.

Cooling house:  IBMspeak for a bureaucratic non-job into which a youngish member of IBM staff has been shunted. Apparently there’s still hope for you if you’re young, which is why IBM is keeping you in suspended animation in the cooling house. If you pass the magical age of 45 and you’re still in a cooling house, the cooling house becomes a Cemetery. See also Parking lot.

Cooperative processing:  Generic term for systems in which the processing is spread across two or more systems. The most common use of cooperative processing is where a system is provided partly on an intelligent workstation (the user interface) and partly on a minicomputer or mainframe (database access, application processing, etc). SAA was designed as an architecture for cooperative processing, and OfficeVision was one of the first whole-hearted attempts by IBM to create a cooperative application. The term has rather gone out of fashion, and people tend to call the concept client/server these days.

Coordinator system:  The system in a RACF data sharing group where a RACF command is entered by a system operator or administrator and is propagated to the entire group.

COPICS:  Communications Oriented Production and Information Control System. Venerable CIM MRP software for the mainframe. Enhanced October 1989 with shop floor interfaces and CDF compatibility. SQL versions announced October 1989 as a part of CIM Advantage. COPICS Enhanced (July 1991) is a COPICS re-vamp by IBM, General Electric, and some third parties. Obsolete. See also CATIA, ENOVIA.

Copper:  IBM was the first company to commercially manufacture computer chips with copper instead of aluminum, for the metallic circuitry linking transistors on the semiconductor. IBM overcame problems of copper leaching into the silicon with a patented fusion barrier. The result was smaller chips that integrated more complex functions, used less power, and required less cooling. Announced September 1997.

COPR:  Control operator control block.

Co-processor:  An additional processor within a CPU which off-loads (it’s also known as an offload engine or IOP – Integrated Offload Processor) specific tasks from the main CPU. Co-processors provide a very effective way of building parallelism into each mainframe processor and IBM has always provided mathematical co-processors. In September 1990 a cryptographic co-processor (see Integrated Cryptographic Feature) was announced, and in February 1993 a data compression engine.

CORBA:  Common Object Request Broker Architecture. Set of standards for distributed object management from the Object Management Group (OMG). Supported in IBM’s SOM and DSOM architectures.

CORMES:  Communications Oriented Message System. VSE/MVS system for building electronic mail systems under COPICS. Withdrawn August 1994.

Corporate portal:  A company-specific Web portal that provides selective access to the company’s Intranet and information systems resources. See also WebSphere Portal Server.

Corrective Service Diskette:  A diskette provided by IBM that includes updates to a program designed to resolve problems. The diskette is distributed to registered service coordinators for resolving user-identified problems with previously installed software.

Corsair:  IBM code name for a 95mm, high performance disk which it sells on the OEM market, and uses in its own products. Part of the same family of devices as Allicat.

Cortina:  See 4391.

COS1:  Corporation for Open Systems. US corporation, similar to the European SPAG, which aims to promote the use of OSI standards. Members (including IBM) are vendors and users. By mid 1993 it had got into such a state squabbling over TCP/IP that it decided to re-organize itself completely. Dormant.

COS2:  Class Of Service. A mechanism within SNA which assigns virtual routes and priorities to sessions.

COSE:  Common Open Software Environment. Alliance (March 1993) between IBM, HP, Sun, Unix System Labs, and others aimed at improving interoperability between their respective Unix workstation platforms. The agreement includes a Common Desktop Environment, based on HP VUE, OSF Motif, and Sun ToolTalk; marketing agreements covering OSF DCE and Sun ONC; and a range of draft specifications concerning multi-media, object-orientation, networking, graphics, and system management. COSE was probably inspired by Windows NT paranoia, but it’s good news for Unix users. See also CDE, Spec 1170, WABI. Dormant.

COTS:  Commercial Off-The-Shelf software. Generic term for shrink wrapped commercial products which are not custom designed for a specific user.

Country code:  The 3-digit number in X.25 that precedes the national terminal number in the network user address for public networks.

Coupling:  Generic term used to mean connecting of processors together into a more or less tightly-knit computing complex. Used specifically by IBM to mean the connection of multiple eserver zSeries 900 processors in a sysplex.

Coupling Facility:  Hardware from IBM, such as the 2064 model 100, where common tables can be shared in a sysplex, for high speed caching, update locking of shared data, list processing and workload balancing between multiple processors.

Coupling Facility Control Code:  The code (small operating system) implementing the Coupling Facility.

Coupling Facility Structure Sizer Tool:  A tool on IBM’s Web site that can be used to calculate storage usage within a Coupling Facility for the major IBM software products that use it.

Coupling Link:  See CF Channel.

COW:  Character Oriented Windows. A Microsoft user interface employed in LAN Manager for the user and administrator interfaces, where it presents an appearance very similar to OS/2 Presentation Manager.

CP:  Control Program. The collection of software modules that make up the core (nucleus) of z/VM.

CP/67:  A very early IBM mainframe operating system which eventually evolved into VM. Originally written for the S/360 Model 67, the only S/360 with the DAT hardware required to do paging in support of virtual memory.

CP/88:  Concurrent operating system developed by IBM for use within the NetView/PC product. Capable of running a PC-DOS program as a task. Obsolete.

CP/MSU:  Control Point Management Services Unit.

CPA:  Cisco’s Channel Port Adapter – a smaller version of the CIP for Cisco 7200 family bridge/routers.

CPAR:  Customer Problem Analysis and Resolution. Process in which a customer identifies the cause of a problem and the appropriate fix. It brings sunshine into IBM’s life when customers who carry out a CPAR, issue an APAR. Obsolete.

CPC:  Central Processor Complex. Synonym for CEC.

CPE:  Customer Premises Equipment. Generic term for telecommunications equipment – handsets, PBXs, modems, etc – that lives on the customer’s rather than the PTT’s premises.

CPF:  Control Program Facility. The operating system for the System/38. Highly integrated, with database and communications facilities all tied in to the basic system (cf. the mainframe operating systems which comprise a minimal set of core functions and a mass of subsystems – VTAM, VSAM, CICS, IMS, DB2, etc). OS/400 builds on and expands CPF. Support for CPF was withdrawn mid 1992.

CPI:  Common Programming Interface. The part of SAA which specified the languages conforming to the SAA. The idea was to make it possible to write an application in one of the SAA languages or application generators and then run it on any SAA architecture. The initial presentation by IBM focused on software portability, moved to productivity improvement, and then to support for client/server (it would have saved IBM a lot of trouble if it had just said that reducing the number of programming languages is self-evidently a good thing). CPI components include CSP1, REXX, COBOL, C, FORTRAN, RPG, Resource Recovery Interface, Language Environment Interface.

CPI-C:  Common Programming Interface for Communications. A superset of IBM communications verbs containing bits of APPC/VM, TSAF, and SRPI. Provides a high-level interface to APPC, and consists of 30 standard calls available in SAA high-level languages and other subsystems, including consistent APPC interfaces. CPI-C licenses (which IBM offered at a knock-down price) have been taken up by many major vendors, and it rapid becoming an industry standard (X/Open took it up). Version 2 May 1994 introduced full duplex, non-blocking calls, and OSI enhancements.

CPI-CI:  Another name for CPI-C.

CPI-M:  Common Programming Interface – Messaging.

CPI-RR:  Common Programming Interface for Resource Recovery. The bit of SAA for controlling access to a TP resource recovery subsystem.

CPLOG:  The IMS Checkpoint Log.

cps:  Characters per second.

CPSA:  CallPath Services Architecture. See Callpath.

CPU:  Central Processing Unit. Processor. The part of a computer that executes instructions.

CQS:  See Common Queue Server.

CRAD:  Customer-Requested Arrival Date. IBM term for when you want their product delivered.

CRAM:  Consolidation, Rationalization, Automation, Management. A program which IBM applied to itself in the early 1990s to rescue itself from the mess it had fallen into.

CRC:  Cyclic Redundancy Check. An error detection and/or correction mechanism based on cyclic codes. Or the storage location used to store CRC value for a block of data.

CREN:  Corporation for Research and Educational Networking. A large computer network formed after the merger of BITNET and CSNET. Headquartered in Washington, D.C.

CRL:  See Certificate Revocation List.

CRM:  See Customer Relations Management.

CRMF:  Certificate Request Message Format. The X.509 Internet standard as defined in RFC 2511.

Cron table:  Chronological table. A table in AIX that is used to schedule application programs and processes.

Cross Platform Extension:  A SCSI to ESCON gateway, based on Seascape architecture, that allows zSeries 900s to share RAMAC2 storage with UNIX and Windows servers.

Cross System Coupling:  See XCF.

CRT:  Cathode ray tube. And computer monitors built with them. Similar technology to a television picture tube. The once-popular term was rarely heard until the late 1990s when it was used to differentiate from the emerging LCD monitor technology that became practical for more than just laptops.

CRU:  Customer Replaceable Unit. A unit replaced lock, stock, and barrel by the customer if it breaks. See FRU.

Cryptanalysis:  Interpreting cipher text without being given the key.

Cryptoanalysis:  Less common spelling for cryptanalysis.

Cryptographic Coprocessor:  See CMOS Cryptographic Coprocessor, PCI Cryptographic Coprocessor.

Cryptographic hardware:  A specialized processor for providing system security. It is faster and more secure than software encryption and less vulnerable to corruption by unauthorized users. See also 4758, CMOS Cryptographic Coprocessor, PCI Cryptographic Coprocessor.

Cryptography:  Designing an algorithm for cipher text.

Cryptology:  The mathematics behind cryptography and cryptanalysis.

Cryptolope:  A mechanism invented by IBM as part of its infoMarket service, which lets owners of digital information distribute it over the Internet securely, while ensuring payment for its use. Potential users can receive a cryptolope, but can only see a headline; the useful information is inside the cryptolope, and the user can choose whether to open and pay for it. Information can be passed on to other users, who in turn must decide whether to unlock and pay for it.

Cryptolope clearing center:  Provides server support for cryptolopes, including registration, authentication, key transformation and management, event logging, and access to billing services.

Cryptolope Live:  The next generation of the cryptolope secure Java component. It will be able to create information objects, components that could be static content or content linked by an IBM subset of Java surrounded by business logic. Previously a cryptolope opener was required on the desktop to add the business logic, but Live makes the containers more generic and easier to distribute by having the rules inside the containers. Announced September 1997. But nothing seen or heard since.

Cryptolope opener:  Enables users to access or purchase the contents of a cryptolope container by requesting keys to decrypt the content from a clearing center.

Cryptolope packer:  Assembles the content to be enclosed in a cryptolope container, encrypts that content with appropriate keys registered with a clearing center, and allows the content owner to specify the terms and conditions, prices, usage rules, and access restrictions for that content.

Cryptosystem:  The world’s first public-key encryption scheme that provides a mathematically proven uniform level of data encryption. It is based on the difficulty in finding what is called the unique shortest vector in an n-dimensional lattice, which is apparently impossible. Announced May 1997 but not a product yet.

CS1:  Customer Service.

CS2:  See Communications Server.

CSA1:  Common Service Area. Part of the common area of z/OS. Mainly used for data for VTAM, IMS1, etc.

CSA2:  Corporate Service Amendment. IBM maintenance scheme.

CSA3:  Callpath Services Architecture. See Callpath.

CSAT/400:  Central System Administration Tools/400. AS/400 software (February 1992) which allows a central AS/400 to control a network of AS/400s running DSAT/400. Facilities include planning and tracking of file distribution, problem management, distribution of fixes, configuration audits. Withdrawn December 1995.

CSC:  Cross Systems Consistency. A philosophy which became SAA when it grew up.

CSCM:  Central Site Change Management. Software allowing 3174 firmware to be updated electronically from a central site. Requires NetView/DM.

CSCW:  Computer Supported Collaborative Working. A self-explanatory term for the activities supported by groupware. Used by IBM in response to Microsoft making first claim on the less tortuous term workgroup computing.

CSD1:  Corrective System Diskette. A diskette, or more usually quite a number of diskettes, supplied by IBM to correct bugs in OS/2 software.

CSD2:  Communications System Division.

CSD3:  CICS System Definition.

CSE:  Cross System Extensions.

C Set++:  IBM system for developing C++ programs. Included 32-bit compiler, class libraries, full function browser, etc. Available on several platforms before being withdrawn.

CSF1:  COBOL Structuring Facility. See COBOL/SF.

CSF2:  Common Storage Format. A specific implementation of the Fixed Block Architecture (see FBA), long recognized as the best format for delivering predictable response times from DASD. As well as simplifying data formats, the CSF allows new facilities, including: backup while open, backup at record level, enhanced file sharing and improved space allocation. Also known as M4K.

CSF3:  4690 Controller Services Feature. See StorePlace.

CSFI:  Communications Subsystem for Interconnection. An early 1991 VTAM application which acts as a protocol converter between SNA and OSI environments. Uses NPSI on the FEP. It appears to be aimed at the e-mail, videotext, and EDI markets, and should simplify 3270-to-ASCII connection. Although the Networking Blueprint wasn’t around when it first appeared, CSFI belongs to the Multi-Protocol Networking layer of the Blueprint, as it allows SNA and non-SNA terminals to interoperate with SNA and non-SNA applications through different types of networking facilities, like SNA, TCP/IP, and OSI. Enhancements in January 1993 included improved TCP/IP (MVS only), use of VT220 applications from 3270, and enhanced X.25 performance. VSE/ESA and z/VM support has ended, but new releases continue to appear for z/OS.

CSI1:  Copy Screen Image. Facility on AS/400 which allows the screen image on one workstation to be copied to another local or remote workstation. Used for Help Desk activities or remote diagnosis and repair.

CSI2:  Computer Security Institute.

CSL:  Callable Service Library. Package of VM/CMS Assembler routines that can be stored as an entity for use by a high-level language, REXX, or Assembler.

CSMA/CD:  Carrier Sense Multiple Access/Collision Detection. A LAN protocol in which the workstations all listen to a common channel, and wait for a lull before transmitting; if two channels transmit at the same time (i.e., there’s a collision), both wait for some suitable (i.e., different!) period of time before trying again. It’s a terribly egalitarian system since all the workstations have equal access rights and privileges, and hence it’s difficult to manage explicitly – a point which IBM reiterates endlessly. Used in the Ethernet and PC/Network LANs and within the IEEE 802.3 standard. cf. Token passing.

CSNET:  Computer Science Network. A large computer network, composed of universities, research labs, and some commercial companies mostly in the United States but with international connections. Now CSNET and BITNET have merged, it is a component of the Corporation for Research and Educational Networking (CREN).

CSO:  Consistent Sign-On.

CSP/AD:  The part of CSP1 providing the development environment. Obsolete.

CSP/AE:  The part of CSP1 providing the run-time (execution) environment. Obsolete. See also EZ-Run.

CSP/AG:  See EZ-Prep.

CSP/Q:  Query/Report Writer for CSP users. Provides casual access to VSAM or CMS files, mainly for non-DP users. Obsolete.

CSP1:  Cross System Product. IBM application generator. Over the years, it ran on quite a number of environments including the AS/400, PC-DOS and OS/2 workstation, 8100 and mainframe running VSE/ESA, z/VM, z/OS and DPPX/370. At one time CSP was IBM’s strategic 4GL, but by December 1997 it had been withdrawn from all platforms, with VisualAge Generator the suggested replacement.

CSP2:  Cooperative Software Program. An agreement between IBM and an Independent Software Vendor (ISV).

CSS:  Channel SubSystem.

CST:  Computer Supported Telephony. Another name for Computer Telephony Integration. See CTI.

CSTA:  Computer Supported Telecommunications Applications. An ECMA interface standard for PABX-computer communications. IBM and Ericsson worked together to create CSTA-based links between Ericsson PABXs and Callpath products.

CSV:  Comma Separated Value. Free format file standard for PCs in which a comma is used for separated fields (text is delimited by quotation marks).

CSW:  Channel Status Word. The word in main store where channel status information is held. The operating system looks at the CSW to find out whether a channel (I/O) operation has completed successfully.

CT:  Control Terminal.

CTC:  Channel-To-Channel. The technique of connecting channels, allowing data transfer between two mainframe systems at channel speeds over short distances. Used by IBM subsystems such as JES3 and VTAM. CTC connection is useful where faster communication than can be provided by a communications link is required.

CTCA:  Channel-To-Channel Adapter. Device for directly connecting the channels of two machines to one another. CTCAs have been replaced by the integrated CTC function in the channels of the ES/9000 and newer mainframe systems.

CTG1:  Computer Task Group. System integrator in which IBM took a 15.3% stake in May 1989 as part of its program of getting into the systems integration market. CTG bought back IBM’s share in December 1994.

CTG2:  See CICS Transaction Gateway.

CTI:  Computer Telephony Integration. Generic term for systems – àla IBM CallPath – which integrate computer and telephone systems. aka CIT and CST.

CTL:  See Certificate Trust List.

CTR:  Computing-Tabulating-Recording. The company which in February 1924 became International Business Machines (IBM).

CTS:  Common Transport Semantics. A layer within IBM’s Networking Blueprint which acts as an interface between the application and the underlying protocols, and, in effect, makes applications independent of the network across which they run. See also MPTF, MPTN.

CUA1:  Common User Access. The part of SAA which specifies the ways in which the user interface to systems is to be constructed. Includes standards for such things as the position of items on screens, use of mouse, meanings of terms, etc. There are two main versions of the CUA based on different models of the user interface – the graphical model for the Programmable WorkStation (PWS), and the entry model for the Non-Programmable Terminal (NPT). There’s also a version which provides the interface to OfficeVision, and a text subset of the graphical model which enables you to build interfaces on NPTs so that they look vaguely like proper WIMPS environments. Note that the CUA does not require IBM hardware or software – it can be implemented using Windows, Motif, OpenLook, etc.

CUA2:  IBM Computer Users’ Association. The UK IBM users association.

CUA 87:  The original CUA1 specification built around the 3270 dumb screen.

CUA 89:  The version of the CUA1 built around the programmable workstation, and based on the WIMPS notion.

CUA 91:  The version of the CUA1 which builds on the concept of object orientation. The base technologies for CUA 91 were Easel and Smalltalk/V.

CUD:  See Capacity Upgrade on Demand.

CUoD:  See Capacity Upgrade on Demand.

Current:  IBM PIM software introduced December 1989 for creating simple personal databases. It’s a single user DOS product incorporating a run-time version of Windows, and includes word processing, calculation, file transfer, and hypertext. Available as a front-end to OfficeVision/400 from March 1993, and as a front end to OfficeVision/MVS and VM from April 1993. And upgraded to run under Windows 3.x. The last Current product was withdrawn August 1997.

Current Connect Group:  The RACF group assigned to the user at logon.

Current Security Label:  The RACF security label assigned to the user at logon.

Customer Relations Management:  Focusing, on an on-going basis, on how an organization deals with its customers.

Customer value pricing:  IBMspeak for not having a price list. The idea is that the customer pays whatever he thinks the product is worth, rather than a notional (and probably heavily discounted) list price. In effect it meant that IBM had stopped publishing its price list. Introduced worldwide in February 1993 (the same principle had been in use in the UK since early 1992).

CUT:  Control Unit Terminal. A mode of operation used by the 3274 where the device LU logic is maintained in the controller on behalf of the terminal; i.e., the controller, not the terminal, interprets the 3270 datastream. The 3278, 3178, and other very dumb terminals use this mode. cf. DFT.

CUTPWHIS:  A free utility from IBM that removes non-usable passwords from the RACF password history.

Cut-through:  Switching mode used by LAN switches (e.g., IBM 8270) and WAN switches where the switch starts to forward bits that make up a frame to its destination as soon as it has determined the relevant destination port without waiting to receive the end of the frame and checking whether it is error-free. Opposite of store and forward.

Cut-through routing:  Communications technique of the store and forward ilk. Unlike conventional store and forward in which a whole frame of data is received before it is forwarded, in cut-through routing, the node begins to forward the data after it has received the first few characters. Used within the Serial Storage Architecture.

CVOL:  Control VOLume. Obsolete, but still in use, z/OS catalog stored in a non-VSAM dataset with the name SYSCTLG.V followed by the VOLSER. Replaced by ICF2.

CVT:  Communications Vector Table. The central control block in the z/OS environment. Can be used in read-only mode by applications programs to access certain system tables and control areas related to the active address space.

CWM:  The OMG’s Common Warehouse Metamodel, a standard model of data warehouse metadata.

CWS:  See CICS Web Support.

Cylinder:  The tracks, in an assembly of magnetic disks, that can be accessed without repositioning the access mechanism.

Cypress:  Combined telephone and computer terminal (ASCII) which emerged during IBM’s short-lived marriage to Rolm.

Cyrix:  Semiconductor manufacturer with a particularly strong presence in the Intel-compatible market. After a protracted legal battle with Intel, Cyrix won the right to make Intel clones. From early 1994 IBM manufactured Cyrix’s 486 chips for use in its own machines and for sale in the open semiconductor market.