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A glossary of terms important to IBM mainframe machines

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E1:  The European equivalent of a T1 line. See T1.

E0-E6:  E0, E1, E2, E3, E4, E5, E6. ITSEC certification of software products based on security assurance levels, EO being inadequate.

EAB:  Enterprise Address Book. Obsolete IBM standard for electronic mail.

EAC:  Extended Access Control.

Eagle:  Code name for aborted project to create an IMS1-DB2 bridge. Also the code name for Amdahl’s ES/9000 basher, the 5995, and for an OS/2 Warp server project (late 1995).

EAI:  Enterprise Application Integration. A generic term applied to a variety of software packages that aim to co-ordinate independent applications within and outside an organization. See also WebSphere Business Integrator.

Early Support Program:  See ESP1.

Early Test Program:  Scheme which gives third-party software suppliers access to new IBM system software before it becomes generally available (they get inexpensive test time, plus documentation and technical support). Used by IBM to promote certain key strategies where a healthy supply of third-party software is essential for the promotion of IBM’s own products.

Early Token Release:  Technique introduced into the IBM TRN late 1989 to speed up traffic. A station normally has to wait for its data packet to come back round the ring before it can release the token for somebody else to use; on 16Mb rings this can be very wasteful. Early Token Release allows a station to release the token before its message has come back (thus there will be two tokens on the ring at the same time); according to IBM, this can increase utilization of the ring by up to 90%.

Easel:  See ESL2

EasySync for Notes:  Lotus software that provides bi-directional synchronization between Notes and an IBM WorkPad or 3Com Palm Computing Device.

EBCDIC:  Extended Binary Coded Decimal Interchange Code. Coded 8-bit character set (giving 256 characters) used in IBM minis and mainframes, and SNA. One of two character codes used in IBM kit. See also ASCII, Unicode, BCDIC.

e-business:  All forms of business conducted electronically across the Internet through Web sites. See also Business to Business.

EC:  Engineering change.

ECA:  Electronic Commerce Association. An independent, UK-based, non-profit-making organization which provides information regarding electronic commerce. Merged with the Article Number Association in October 1998. The new organization is known as e center UK, although the official name is the Association for Standards and Practises in Electronic Trade – EAN UK Ltd.

ECB:  Event Control Block. Control block used for the control of asynchronous processes in IBM mainframes.

ECC:  Error Checking and Correcting. Memory technology with extra bits added for detecting bad memory and often recovering its contents.

ECC-P:  Error Checking and Correcting Parity. Memory technology used in some PS/2s. Now simply known as ECC memory.

ECF:  Enhanced/Extended/Enhancement Connectivity Facilities. Suite of programs – vintage mid 1986 – providing PC to mainframe link. In effect ECF transformed TSO and VM1 into information servers for PC users (virtual disks, virtual files, virtual print, and file transfer with application/character format translation) using 3270 datastreams. Makes use of SRPI which provides ECF’s API. OS/2-CMS servers announced May 1990, and OS/2-TSO servers October 1990. Withdrawn March 1997.

ECFORMS/VM:  Electronic Forms Management System/VM. Creates forms on-line, and routes them electronically. Positioned by IBM as a workflow management tool. June 1993 announcements included performance enhancements and integration with OfficeVision/VM. Withdrawn June 1997.

ECI:  See CICS External Call Interface.

ECKD:  Extended Count Key Data. See CKD.

ECL1:  Enterprise Communication Link. At one time IBMspeak for an all singing, all dancing, all (or largely) unspecified local/wide area network.

ECL2:  Emitter Coupled Logic. A semiconductor technology once used in the very fast logic circuits of large IBM computers (cache, processors, etc). High performance ECL manufacture was a difficult process, and even IBM had trouble getting its production yield up to the required levels – although it seemed to crack the problem with the 9121 and 9021 models. Obsolete. CMOS is the sole technology used in mainframe processors today.

ECLPS:  Enhanced Common LISP Production System. See Common LISP.

ECMA:  European Computer Manufacturers’ Association, of which IBM is a member. Founded in May 1961. Renamed in 1994 to European Association for Standardizing Information and Communication Systems, though the acronym ECMA remains the same.

ECMAScript:  A scripting language, based on Netscape’s JavaScript, developed by the ECMA.

ECN:  See TCP Explicit Congestion Notification.

e-commerce:  A subset of e-business, that deals with the entire process of buying and selling items over the Web.

ECPS:  Extended Control Program Support. Firmware introduced to improve z/VM performance on medium-sized machines.

ECPS/VSE:  Extended Control Program Support/VSE. VSE/ESA implementation of virtual storage that does not require software to translate virtual into real addresses.

ECS:  Electronic Customer Support. Range of IBM services available electronically, initially over dial-up and dedicated lines, now mostly over the Internet. Includes remote diagnostics, marketing, and so on. IBMLink was an early example. There is an ECS service built into the OS/400 operating system.

ED:  See Executive Decisions/VM.

Eden:  Project at IBM in Austin, Texas aimed at developing processors using heavily parallel configurations. The SP1/SP2 and Parallel Transaction Server probably owe much to the Eden project.

EDI1:  Electronic Document/Data Interchange. Generic term for a set of techniques worked out in the 1980s for allowing organizations to electronically exchange documents without the use of paper, usually over a third party’s network. EDI services are provided by many network vendors, who also do the protocol conversion, formatting, incompatibility resolution, etc. IBM supported EDI through VANS such as INS and IN. Internet-based initiatives, most notably XML, are replacing EDI, reducing both cost and complexity. IBM EDI Services were rebranded as IBM Interchange Services for e-business in August 2000. See EDIFACT, expEDIte, SGML.

EDI2:  Execution Diagnostic Indicator.

EDIFACT:  EDI For Administration Commerce and Trade. International EDI standard developed by the ISO standards body and agreed with ANSI. Supported by IBM in the expEDIte products.

EDI Services:  Rebranded as IBM Interchange Services for e-business in August 2000.

EDMSuite:  Replaced by Content Manager.

EDP:  Electronic Data Processing, now more commonly known as Information Technology, though Computing is a term that never goes out of fashion.

EDS:  Extended DataStream. Additional attribute information provided with each character sent from a mainframe – color, blinking, underline, etc.

EDT-DistribuTAPE:  Extended Data Technology. Software from Gresham Software marketed by IBM and announced August 2001. Allows multiple TSM2 servers and LAN-free clients to dynamically share multiple tape drives installed in a StorageTek library environment.

Education Allowance:  A discount offered by IBM to qualified educational institutes. For z/VM, for example, it amounts to 15%.

EDX:  Event Driven eXecutive. Operating system for the defunct Series/1 family of minicomputers.

EEP:  Early Experience Program. IBMspeak for beta test. See also beta, alpha2, alphaWorks.

EEPROM:  Electrically Erasable Programmable Read Only Memory. A storage device exploiting a technology similar to EPROM but with the ability to discharge the floating gate electrically. Usually bytes or words can be erased and reprogrammed individually during system operation.

EEROM:  Electrically Erasable Read-Only Memory. Generic term for a type of ROM which can be erased although not usually by the user of the device in which the EEROM is installed.

EF:  Extended Function.

EFM:  See Enterprise Firewall Manager.

EFP:  See Extended Facilities Product.

EFT:  Electronic Funds Transfer. Generic name for systems which transfer cash around between accounts at the speed of light, thereby preventing people using delays in cheque clearance to keep themselves solvent.

EGA:  Extended Graphics Adapter. Successor to the CGA as the IBM PC graphics standard. Capable of a maximum resolution of 640x350 pixels in 16 simultaneous colors from a total of 64 possible colors. Itself succeeded by the VGA standard.

EHLLAPI:  Emulator (sometimes Extended) High Level Language Application Program Interface. Still used (and supported) for 3270 terminal emulation on Windows workstations.

EIA:  Electronic Industries Alliance (originally Association). An organization of electronics manufacturers, of which IBM is a member, that develops industry standards.

EIB:  Enterprise Information Base. IBM term for a type of Management Information Base (MIB) which contains planning and long term control information. cf. CIB.

EIDE:  Enhanced IDE.

EIF:  See Tivoli Event Integration Facility.

EIO:  Early Installation Offering.

EIP:  IBM Enterprise Information Portal. Multiplatform client software intended to provide access to structured and unstructured data across an entire organization.

EIS1:  Enterprise Information System. See Enterprise.

EIS2:  Executive Information System (also known as ESS – Executive Support System). End-user systems for really important people. EISs are most widely used to provide Briefing Book summaries of key statistics in the business, so that senior managers can understand where the business is at, and so make sensible decisions. EISs are often confused with DSSs (Decision Support Systems, see DSS1), the key difference being that DSSs are designed mainly to enable their users to program the system themselves to support modeling and prediction, whereas EISs are programmed by professional DPers to create customized information displays for bigwigs. EISs also use a wide variety of input sources – the corporate database, public databases, line managers’ data, etc. Executive Decisions/VM was IBM’s first serious attempt at an EIS. See also DIS2.

EISA:  Extended Industry Standard Architecture. Open standard for I/O buses for industry-standard computers, developed by nine PC vendors, excluding IBM. Comprises an extension of the AT-compatible 16-bit bus to 32 bits, and was designed to stop IBM’s MCA from becoming the industry-standard 32-bit interface (although IBM’s failure to show any real benefits from MCA seems to have done that fairly successfully anyway). EISA has 32-bit address and data bus extensions for memory beyond 16MB, and 32-bit direct memory access. See also Busmaster, MCDA, ISA.

EJB:  Enterprise JavaBeans. A server-side, transaction-oriented extension to the JavaBeans component model specification published by Sun. EJB are JavaBeans, but have no user interface and are designed to run within a special EJB container. In principle, any properly coded EJB should run within any fully compliant EJB container.

ELA:  Enterprise License Agreement. An IBM customer contract.

ELAN:  Emulated LAN.

ELC:  Extended License Charge. An IBM pricing option based on the capacity of a machine as stated in MSUs. For example, it is available for z/VM, but not z/OS.

Electronic commerce:  Conducting business electronically. The term has come to encompass a considerable number of technologies, processes and strategies ranging from traditional EDI to Web-based transactions. Now more commonly known as e-commerce, cf. e-business. IBM has committed considerable resources to electronic commerce initiatives. See Energy Network Exchange, Insure-commerce, PetroConnect.

Electronic Customer Support:  See ECS.

Electronic purses:  Devices which exploit smart card technology to store cash electronically on a microchip, to produce a pre-payment card which can then be used to buy a range of goods and services. This theoretically allows the safe transfer of currency to another electronic purse. In the UK, the Mondex electronic purse trial started mid 1995.

Element:  In z/OS, a base function that can be dropped and replaced by a non-IBM product, but all z/OS integrated testing results and performance claims are voided with such replacement.

ELIAS:  Entry-Level Interactive Applications System. Early application generator from IBM. Obsolete.

ELS:  Entry Level System.

EmailConnect:  E-mail service on the defunct IBM Information Network. See IN.

Embedded Security Subsystem:  An IBM security chip and client security software for NetVista, PC 300PL and IntelliStation systems.

EMC:  ElectroMagnetic Compatibility. A problem which causes some electrical devices to interfere with others. This, of course, is terribly anti-social and inconsiderate. IBM was very proud of the fact that you don’t get EMC problems with the MicroChannel architecture (it droned on at great length about the fact in its publicity), because the connectors are properly grounded. Isn’t it great to know that even the largest corporations have a heart?

EMCS:  Enterprise Management Control Series. Set of IBM mainframe programs for project control based on critical path method. Withdrawn June 1990.

EMCS AFMT:  EMCS Advanced Function Management Tools. Part of EMCS. Withdrawn June 1990.

EMEA:  The IBM sales region which covers Europe, the Middle East, and Africa.

EMI:  ElectroMagnetic Interference. aka RFI.

EMIF:  ESCON Multiple Image Facility. June 1992 facility which enables sharing of ESCON channels among PR/SM logical partitions, allowing users to use fewer channels to support the same I/O load. Originally available on 9021s only, but extended to 9121s in February 1993. Now a standard hardware function of eserverzSeries 900.

EMO:  Extended Maintenance Option. Advanced payment, fixed term maintenance agreement introduced in June 1988 for PS/2s. Expanded to other hardware, but finally withdrawn February 1999.

EMS:  Expanded Memory Specification. See LIM EMS.

Emulation Program:  See EP.

ENA:  Extended Network Addressing. Feature of SNA (VTAM and NCP) enabling the construction of extremely large (up to 8 million LUs and 255 subareas) networks. The network address is split into an 8 bit subarea, identifying processors and communications controllers, and a 15 bit element, identifying network resources. One of two ways of building very large SNA networks, the other being SNI.

Encapsulation:  In object-oriented programming, a technique in which data is packaged, usually to hide the inherent details of an object.

Encina:  ENterprise Communication In a New Age. Multi-platform OLTP from IBM subsidiary Transarc, typically sold as a toolkit. Encina formed the basis of the obsolete CICS/6000 and CICS/Unix products. Supports DCE. IBM supports Encina in product lines such as WebSphere and VisualAge.

Encina for AIX:  Replaced by the now obsolete Transaction Server for AIX1 January 1997.

Encina Toolkit Executive:  An element of z/OS. See Encina.

Encode:  To convert data into a stream of bits so that it can be transmitted over a serial line.

ENCP:  End-Node Control Point.

Encrypt:  See encryption.

Encryption:  An attempt to translate data (plain text) into a form where the only practical way to reconstruct it is by knowing a specific algorithm (fixed) and a key (can vary).

Energy Network Exchange:  IBM initiative to introduce secure, electronic commerce and information clearing houses across the Internet for electric utilities. Announced November 1996 and nothing has been heard about it since. See Insure-commerce, PetroConnect.

eNetwork:  An April 1997 branding of IBM products that is now obsolete. The host integration products were renamed with the SecureWay brand July 1999.

eNetwork Communications Suite for Windows:  A suite of software produced by IBM’s Network Software Division which combines IBM’s Terminal Emulation Software, LotusNotes mail client, FTP1 software’s TCP/IP stack and client applications, and the Netscape browser. Introduced April 1997. Withdrawn April 1999.

eNetwork Emulator:  IBM’s September 1997 rename of the ARTour Emulator. As with eNetwork Web Express, data from a gateway on the corporate network is compressed for transmission across the wireless network, then decompressed and displayed on the eNetwork Emulator or a browser. Bandwidth consumption is reduced through data caching. Withdrawn December 2001.

eNetwork Firewall:  Renamed SecureWay Firewall.

eNetwork Mobile Equalizer:  Client/server software that extends LotusNotes, MQSeries messaging and Tivoli software distribution to mobile Windows workstations that are disconnected for long periods of time and only have access to low speed (dial-up) access for short periods of time. Announced April 1998. Withdrawn December 1998.

eNetwork Web Express:  IBM’s September 1997 rename of the ARTour Web Express. It consists of an Windows NT 4.0 Server or AIX1 gateway on the corporate network and mobile client OS/2 or Windows software. Data is compressed for transmission across the wireless network, then decompressed and displayed on the terminal emulator or browser. Bandwidth consumption is reduced through data caching. Support ended December 2001.

eNetwork Wireless:  IBM’s September 1997 rename of the ARTour product line. Three major products include eNetwork Web Express, eNetwork Emulator and the eNetwork Wireless Gateway.

eNetwork Wireless Gateway:  Both the eNetwork Web Express and the eNetwork Emulator rely on the AIX-based eNetwork Wireless Gateway server. Replaced by SecureWay Wireless Gateway for AIX July 2001.

Enhanced X-Windows Toolkit:  A collection of basic tools for developing X-Windows application environments in AIX.

ENOVIA:  e-business Product Lifecycle Management (PLM) for manufacturing companies. Developed by Dassault Systemes, also responsible for CATIA. Runs on Windows and AIX, HP-UX, Sun Solaris and SGI IRIX. Where a database is required, DB2 and ORACLE are both supported.

ENQ:  See Enqueue.

Enqueue:  The z/OS expression (often abbreviated to ENQ) for requesting resource serialization. ENQ can be used to put a user-named entry in the system resource queue in order to prevent another program using a serially usable resource. See also DEQ.

Enterprise:  IBMspeak for an organization. Suddenly we didn’t work for companies or firms any more – we worked for Enterprises; and we don’t do DP, EDP, or MIS any more – we worked in Enterprise Information Systems. Yet another leap forward for computing, courtesy of the jolly blue giant.

Enterprise Alliance:  Obsolete IBM service in which IBM went into an organization, looked at its systems, and then tied them all together to present a nice tidy, coherent system image to all the users. Initial Enterprise Alliance projects were directed at integrating discrete PS/2 systems.

Enterprise bid:  Another name for revenue bid.

Enterprise Extender:  IBMspeak for routing HPR over IP1.

Enterprise Firewall Manager:  An element of the SecureWay Firewall that facilitates the configuration and management of multiple firewalls from a central location.

Enterprise Information Portal:  See EIP.

Enterprise Integrator:  Lotus Enterprise Integrator. Server-based data distribution software that exchanges data between Domino and a large number of host and relational applications, including DB2, Oracle, Sybase, ODBC, EDA/SQL and ERP1 applications. Formerly NotesPump.

Enterprise JavaBeans:  See EJB.

Enterprise Performance Data Manager/MVS:  DB2 SystemView software, announced June 1993. Collects system management and performance data (from DB2, DFP, DFSMS, EREP, JES2/3, MVS, NetView, RACF, RMF, and VM) in a DB2 database, and generates tabular or graphical reports. Includes an OS/2 reporting component, and is able to support connected AS/400s and RS/6000s. Went through several renamings before becoming Tivoli Decision Support for z/OS.

Enterprise Solution Builder:  Lotus development and runtime service for integrating non-Domino applications with Domino applications.

Enterprise Storage Server:  A second-generation SeascapeRAID 5 disk storage system that concurrently supports zSeries 900, iSeries 400, pSeries, NUMA-Q, Sun, Data General, DEC, HP, Compaq, NetWare, and Windows servers via FICON, Fiber Channel, UltraSCSI and ESCON connections. Up to 13.9TB capacity. Announced July 1999.

Entity:  A user, group or resource defined to RACF.

Entity-relationship:  Generic term for a formal technique for modeling business processes and data. An entity is anything describable by data, and entities have relationships to other entities. The entity-relationship technique is particularly suited to describing data for use in relational databases, and was supported by IBM in Repository Manager/MVS before the latter started pushing up the daisies.

Entry/36:  The 5363. The last of the System/36 product line – well that’s what IBM said at the time, but see Advanced 36. Withdrawn October 1992.

Entry Point:  A product that links to a Focal Point using SNA protocols, and is able to be controlled by a Focal Point in a NetView environment. NCP, 3174controllers, and 3708 network conversion units are all Entry Points. You can think of the Entry Points as being subservient nodes in a network management system.

Entry Support License:  Software pricing for very low-end processors. Currently available for z/VM, but not z/OS.

ENVR object:  A transportable format for ACEE data that allows the ACEE to be recreated without referencing the RACF database.

Envy/400:  Object-oriented, Smalltalk-based language for the AS/400 developed by Object Technology International Inc and sold by IBM. Announced mid 1993. Similar to and replaced by VisualAge in March 1995, which, in turn, was later renamed to VisualAge Smalltalk.

EOCF:  Extended Operations Console Facility 2 (EOCF/2). OS/2 software which enables an OS/2 workstation to act as a central or remote TPF console. Also provides console automation. Announced October 1991.

EOL:  End of Life. The EOL date is the IBM term for the effective date of withdrawal from marketing. cf EoS. See also withdrawn.

EOS1:  Embedded Operating System. A low-end version of the Microkernel designed for handheld computing devices.

EoS2:  End of Service. Date when IBM stops support for a product. cf EOL, withdrawn.

EP:  Emulation Program. Pre-SNA IBM control program resident in a channel attached IBM communication controller (FEP), such as the 3745, that enables it to support physical management of the network. Emulates the functions of either a 2701 data adapter unit, a 2702 transmission control or a 2703 transmission control. Beginning with Release 14, announced September 1998, it was no longer necessary to order and install two separate releases of EP when two separate environments were being run: PEP (with NCP) and stand-alone (without NCP).

EPDM/MVS:  See Enterprise Performance Data Manager/MVS.

EPI:  See CICS External Presentation Interface.

EPIC:  Explicitly Parallel Instruction Computing. Intel architecture used in Itanium.

Epistle:  Expert system for spelling, grammar, and style checking. IBM research project. Obsolete.

EPM:  Enhanced editor for Presentation Manager. An editor in OS/2 used for creating and editing text files.

EPROM:  Electrically Programmable Read Only Memory. A type of storage device in which the data is determined by electrical charge stored in an isolated (floating) MOS transistor gate. The gate can be discharged by applying ultraviolet light to the chip’s surface, erasing the memory contents and allowing the chip to be reprogrammed.

EPS1:  Electronic Payments System.

EPS2:  Encapsulated PostScript. Allegedly portable file format based on Adobe’s PostScript page description language.

E-R:  See Entity-Relationship.

EREP:  Environmental Reporting, Editing, and Printing. Seemingly as old as the mainframe itself, EREP is a free report generator for hardware and some software errors. IBM mainframe hardware service personnel rely upon it. Runs on z/OS, z/VM and VSE/ESA. An element of z/OS, but separately licensed for z/VM.

ERP1:  Enterprise Resource Planning.

ERP2:  Error Recovery Procedure.

Error log:  A dataset or file that contains a record of machine checks on device errors, which are stored for later analysis.

Error record template:  A template in AIX that describes the type of error, its class, description, probable causes, recommended actions for an error log entry.

ES/64000:  Defunct name for the parallel mainframes promised by IBM in October 1993 which eventually became the 9672 and 9673. See Parallel Transaction Server, Parallel Query Server.

ES/9000:  IBM’s family of processors announced September 1990. Featured high-density packaging, bipolar and CMOS, and one and four megabit chips. At launch there were three physical forms of the ES/9000: air-cooled and rack-mounted àla 9370 (the 9221), air-cooled and frame-mounted àla 4380 (the 9121), and water-cooled àla 3090 (the 9021). February 1993 announcements included 18 new models, including an 8-way processor, Asynchronous Data Mover Facility, increased channels, data compression, and 18 new models, bringing the total range up to 46 models. It also saw the emergence of an almost rational model naming system where the last two digits of the model number suffix indicate the number of processors and sides – e.g., a 9021-942 is a four processor, two sided model. Mid 1995 new and more powerful models were announced. Gradually withdrawn in favor of the System/390 all CMOS machines (9672) that were themselves replaced by eserverzSeries 900 October 2000. See also Summit, Foothill, 9021, 9121, 9221.

ES1:  See Expanded Storage.

ES2:  Enterprise Systems.

ESA:  Enterprise System Architecture. See MVS/ESA.

ESA/XC:  ESA eXtended Configuration. z/VM feature which allows CMS applications to create dataspaces, and share them between virtual machines. Announced September 1990.

ESAF:  External Subsystem Attach Facility. Part of IMS TM. Other products can use it to attach to IMS TM, then IMS TM application programs can access resources owned by the attached products. The most common use of ESAF is to allow DB2 to attach so that IMS TM applications can have access to DB2 data.

eSAR:  electronic Solution Assurance Review. Web-based tool which generates IBM product implementation recommendations based on customer input. Designed to speed implementations while mitigating risk.

ESB:  Media name for a rumored new IBM operating system to replace MVS/ESA, supporting 64-bit addressing, expanded storage shared between processors, high-speed fiber optic LAN linking processors in a sysplex, single level storage, etc. z/OS meets some of those criteria. See also Saturn.

ESCC:  ESCON Connection Converter. See ESCON Converter.

ESCD:  ESCON Control Director. See ESCON Director.

ESCE:  Expert System Consultation Environment. See ESE.

ESCE/PC:  Expert System Consultation Environment. See ESE.

ESCM:  See ESCON Manager.

ESCMS:  ESCON Monitor System. Dial-up system which enables users to control and monitor the power supply of devices on an ESCON network – enables you to turn remote equipment on and off from a central site. ESCMS can detect power loss as well as unauthorized intrusion, water leaks, smoke, fire and all sorts of hazards; and it can telephone up the fire brigade or police too!! If you’ve really got things organized, you can turn your computers on with ESCMS, and then control them using TSCF. Announced September 1990. Replaced by SystemView SiteManager Services February 1992.

ESCON:  Enterprise System Connectivity. The high-speed fiber optic channel architecture (using a serial, packet-switched protocol) first available on ES/9000 and 3090-Js and many peripherals. The original ESCON used LEDs and worked at 10MBps over 3km stretches (up to 9km total distance with repeaters). September 1991 IBM announced a laser version (ESCON XDF) capable of working at greater distances. The ESCON architecture also allows multiple controllers to be connected to one ESCON channel, and enables I/O devices to be connected and disconnected with the main system running. The standard fiber optic trunk cable can contain 72 pairs of fibers, giving 72 channel links. June 1992 IBM announced sharing of ESCON channels across PR/SM partitions (EMIF). Replaced by FICON May 1998, though still available. The last version of ESCON runs at 17MBps simplex. See also Paradyne.

ESCON Converter:  Device (also known as ESCON Connection Converter – ESCC) which enables ESCON fiber optic channels to work with traditional devices (ESCC model 1 – the 9034), and ESCON devices to work with traditional channels (ESCC model 2 – the 9035). In effect it’s a protocol converter between the channels using the bus and tag parallel architecture and channels using the serial ESCON architecture. Obsolete.

ESCON Director:  The 9032/9033 device (also known as the ESCON Control Director or ESCD) to which all ESCON channels and control units can be attached and which provides the dynamic switching and reconfiguration – it’s a router or smart switch. ESCON Directors can be attached to one another as well as to channels and control units. Console sharing across ESCON Directors was announced September 1991, and redundancy, concurrent LIC upgrade, dynamic port addition, and extended distance console support in October 1994. ESCON Director support is an element of z/OS. See also 9032, 9033.


ESCON Manager:  SystemView facility (also known as ESCM) under z/OS and z/VM enabling host management of fiber optic connections using ESCON Directors. ESCM monitors and controls local and remote ESCON Director connections. Replaced by System Automation August 1997.

ESCON Monitor System:  See ESCMS.

ESCON XDF:  ESCON eXtended Distance Feature. The laser-driven version of ESCON (announced September 1991) which can work at up to 60km (with repeaters).

ESCS:  ESCON Supervisor.

ESD1:  Electronic Service/Support Delivery. IBM system for electronic delivery of z/OS and z/VM fixes.

ESD2:  Electronic Software Distribution. Once a generic term, now an IBM term referring to a Lotus initiative begun as a pilot project in October 1996, where software products are distributed via the Internet to its channel partners. See also ESD3.

ESD3:  Electronic Software Delivery. Some IBM chargeable software can be downloaded from a Lotus Web site. Both business partners and individual customers can use ESD.

ESDE:  Expert System Development Environment. See ESE.

ESDS:  Entry Sequenced DataSet. VSAM sequential dataset in which the data is held in the order in which it was originally entered (i.e., new records are placed on the end of the dataset). Can be used as a replacement for BSAM and QSAM in z/OS. But most commonly used as a replacement for sequential datasets in VSE/ESA. See also Linear dataset.

ESE:  Expert System Environment. Expert system shell for z/VM and z/OS, announced by IBM in 1985. Less powerful than KnowledgeTool, but more suitable for use by non-professional programmers. ESCE, ESDE and ESCE/PC were associated products, the latter allowing completed ESE applications to run on a PC. The z/OS and z/VM components were withdrawn February 1996, with the PC component withdrawn in a sweep of non-Y2K-tested software in March 1998.

e-security:  Security for electronic commerce on the Internet.

eserver:  A complete replacement of IBM’s hardware server platforms with four new series: zSeries 900, iSeries 400, pSeries and xSeries. Announced October 3, 2000. The e actually has a circle around it, like the a does in the @ symbol.

ESF1:  Extended Superframe Format. Technique for reduction of error rates on T1 lines.

ESF2:  External Source Format. A data format (originally part of AD/Cycle) used to pass data between tools and CSP1 generators. Functions as a universal target language for anyone wanting to write applications for supported platforms. Also used in HighPoint.

ESL1:  See Entry Support License.

ESL2:  Under its original name, Easel, ESL was an OS/2 and DOS screen scraping product designed to convert dumb terminal applications into CUA1-compliant front-ends for the PS/2. In 1989, it was the IBM-recommended tool for developing graphical CUA interfaces. In 1991, IBM announced distributed CICS applications development and CSP1 support, and pulled back support for Easel. ESL now belongs to EslSyndetic, and is "a visual development tool for building workstation applications that can interact with mainframes, servers and databases using a wide variety of protocols."

ESM:  See Tivoli Event Services Manager.

ESMS:  Enterprise System Managed Storage. The stage beyond SMS in which MVS acts as a super-server providing data across a network to all and sundry. Initiated by IBM when it announced the Sun NFS in September 1990, but not spoken of much since.

ESO Hiperspace:  Expanded Storage Only Hiperspace.

Esoteric unit name:  In z/OS, a single installation-specific name that can apply to multiple, usually similar, logical or physical I/O devices. Can be used in JCL DD statements or specified to DFSMShsm to refer to any of a group of devices, reducing contention for a single device.

ESP1:  Early Support Program. The process of giving new products a final run-through on selected users’ facilities. So-called because you need powers of extra sensory perception (another type of ESP) to find out what the software’s meant to do. See also EEP, QIP.

ESP2:  Extreme Support Personalized. Originally, Extreme Support through Personalization. An IBM service offering for iSeries 400 customers. It involves a customized blend of support over the Internet, voice, and on-site support, along with support integrated into the iSeries 400 itself.

ESQL:  Embedded SQL. SQL statements coded explicitly in an application program.

ESS1:  Executive Support System. See EIS2.

ESS2:  See Enterprise Storage Server.

ESSA:  Extended System Service Amendment. Withdrawn in favor of SSA1 in mid 1990.

ESS eSAR:  Enterprise Storage Server electronic Solution Assurance Review. See eSar.

ESSL:  Engineering and Scientific Subroutine Library. ESSL Vector and Scalar/370 was introduced to exploit the vector facility of the 3090 and some ES/9000 mainframes, but not available for eserverzSeries 900. Withdrawn March 2001. ESSL for AIX and Parallel ESSL for AIX are still available.

ESSL/6000:  Version of ESSL for the RS/6000. Announced in January 1990. Replaced by ESSL for AIX.

ESS SAPR:  Enterprise Storage Server Solution Assurance Product Review.

Establishment controller:  What used to be called a Cluster controller.

ESTAE:  Extended Specify Task Abnormal Exit. An z/OS Assembler macro instruction that provides recovery capability and gives functionality to the user-specified exit routine for processing, diagnosing an abend, or specifying a retry address.

ESTOR:  See Expanded Storage.

ET-1:  Industry standard benchmark for OLTP systems. Also known as the Debit-Credit transaction. Sometimes ET-1 is used to refer to a trimmed down version of Debit-Credit.

EtherChannel:  The Cisco System Network Bandwidth Aggregation and Load Balancing technology, called EtherChannel, builds upon standard and 802.3 Fast Ethernet to provide the functionality to aggregate a bandwidth of multiple Ethernet interfaces.

EtherJet:  Family of IBM Ethernet adapters first announced November 1995.

Ethernet:  A baseband LAN technology, originally created by Xerox, DEC, and Intel. Ethernet is the base for the IEEE802.3 LAN standard (although it doesn’t actually conform fully), and, until the advent of the TRN, was by far the most popular high-speed LAN product in the market. IBM now provides a high level of support for Ethernet. See also Gigabit Ethernet, Isochronous Ethernet.

eTill:  An electronic equivalent of a cash register that accepts payment for the goods and services selected for purchase in the IBM Payment Suite. The eTill is used in conjunction with a payment gateway and a payment management system, to complete the financial transactions.

ETM:  Enterprise Transaction Management. IBMspeak for big operational on-line systems.

ETO:  Extended Terminal Option. A separately priced feature of IMS TM that enables workstations to be added or deleted from a live computer system. Does for IMS TM what RDO does for CICS. Announced September 1990.

ETP:  See Early Test Program.

ETR1:  External Throughput Rate. Performance measure in which throughput is specified as transactions/jobs per second of elapsed time. Favored as a benchmark by Amdahl as against ITR which is favored by IBM.

ETR2:  External Time Reference. The fiber optic interface from zSeries 900 processors to Sysplex Timers. A standard feature, having previously been optional on System/390 processors.

ETSI:  European Telecommunications Standards Institute. A standards body created by CEPT in 1988. Headquartered in southern France, ETSI has nearly 800 members from more than 50 countries, many not in Europe.

euro:  The monetary unit of the European Monetary Union (EMU), originally introduced alongside national currencies on the first of January 1999 by Austria, Belgium, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, and Spain. euro notes and coins (hard currency) were put into circulation January 1, 2002, with all national currencies withdrawn by February 28, 2002. The accommodation of the euro by the IT industry has resulted in changes to both hardware and software.

EuroReady:  IBM considers their products to be EuroReady if the product, when used in accordance with its associated documentation, is capable of correctly processing monetary data in the euro denomination and of respecting the euro currency formatting conventions (including the euro sign). See also euro, EuroSign Support.

EuroSign Support:  Support for the special character used as the euro symbol. z/OS has EuroSign support. See also EuroReady.

EUSS:  IBM End User Solution Services. Software products and services for the travel and transportation industry.

Everyplace:  An IBM brand name for software products that support embedded and mobile clients. Announced April 2000. See also MQSeries EveryPlace, Everyplace Wireless Gateway for Multiplatforms.

Everyplace Wireless Gateway for Multiplatforms:  A Unix platform (AIX1 or Sun Solaris) intended to extend existing applications to mobile workers over wireless networks. Supports both WAP and non-WAP clients running on Windows CE, Palm OS, Windows 9x/Me/NT/2000 and QNX/Neutrino. Announced June 2001 to replace the SecureWay Wireless Gateway for AIX (withdrawn December 2001).

Exabyte:  1024 petabytes, 2 to the sixtieth, or 1,152,921,504,606,846,976 bytes.

Exchange Server:  Client/server messaging product from Microsoft, launched after a prolonged beta-testing in April 1996. Originally described as a Notes Killer, turned out to be Microsoft Mail in new clothing. Runs only on Windows NT/200x Server. Despite those facts, it was caught in the late 1990s rush by organizations to standardize on a Microsoft Office and Windows NT 4.0 desktop. Exchange Server seemed the logical choice as a backend to Office’s Outlook. After all, it was made by the same company.

EXCI:  External CICS Interface.

EXCP:  EXecute Channel Program. Usually refers to a z/OS, z/VM or VSE/ESA Assembler macro call to initiate an I/O (more accurately it requests the execution of a channel program on a specific device). The number of EXCPs performed gives the count of the actual number of read/write operations. It can also refer to the type of I/O being performed, as seen, for example, in output from a sort/merge program.

EXDC:  EXternal Data Controller. Within the mainframe extended architecture (on 308x and later processors), the EXDC is a device which carries out I/Os requested by the CPU. The EXDC is the channel of a 3090 machine. Obsolete term.


EXEC/EXEC2:  VM procedural languages, now stabilized by IBM. Programs written in EXEC/EXEC2 are known colloquially as EXECs. IBM has been trying for years to persuade users to migrate from EXEC to REXX.


ExecJet:  See 4072.

ExecJet II:  See 4076.

Executive Decisions/VM:  EIS tool for very senior executives which provides an easy-to-use interface to various MIS tools and services (e-mail, calendar, address book, etc). Uses both z/VM and OS/2 to provide workstation access to mainframe data. Also a version for z/OS announced December 1989. Both withdrawn June 1992.

Exit:  A piece of code that, if executed, stops a program running, typically handing control back to the operating system for exception handling. Exits are much loved by systems programmers who can often be seen on cold winter’s nights huddled around the nostalgic glow of an eserverzSeries 900, yarning and joshing about great exits they worked on in the good old days when mainframes ruled the earth.

EXLST:  VSAM and VTAM terminology for EXit LiST.

Expanded memory:  PC memory conforming to the LIM EMS 4.0 spec. Gives access to more than 640K of memory on Intel processors before the 80386. Used in a number of Windows-based products. EMM386.EXE is an expanded memory emulator for 80386 and newer machines. Obsolete.

Expanded storage:  Option on the eserverzSeries 900, first introduced on the 3090, providing on-board cache memory on the processor side of the channel. Data is paged between main memory and expanded storage in 4096 byte pages synchronously with processor functions. Note that expanded storage is physically different from main memory; it uses a much less complex design (no storage protect keys, no execution circuitry, 4K addressing only) and is 4-6 times more reliable. There seems a distinct possibility that transfers to and from expanded storage may be done quite autonomously at some time in the future (perhaps through the ICE1). See also SSD1, SES.

Expedite:  The IBM Interchange Services for e-business Expedite family of software which translates data into standard EDI formats including ANSI/X12, UN/EDIFACT (including ODETTE), TDCC, and UCS. The first products were announced in April 1989 under the DataInterchange family name with the unusual capitalization expEDIte. DataInterchange became part of IBM EDI Services, which was renamed IBM Interchanges Services for e-business. The DataInterchange name got lost along the way, but popped up in WebSphere as the name for their EDI gateway. The currently available products are Expedite Base for PC-DOS, OS/2, Windows, SCO OpenServer, AIX and z/OS, Expedite/CICS for z/OS and VSE/ESA, Expedite Notification Manager for PC-DOS, Windows, iSeries 400 and z/OS, and Expedite for Windows.

Expert systems:  Computer systems in which the knowledge of experts can be incorporated into the system (hence they are also known (loosely) as knowledge-based systems). An expert system has two parts – a knowledge base, and an inference engine which works on the knowledge base. Such systems are particularly useful for dealing with highly complex tasks (e.g., network management, medical diagnosis) in which it is difficult to make the expertise of specialists sufficiently explicit to incorporate in a conventional computer program. IBM forays into expert systems have included CSF1, DEDALE, Epistle, ESCE/PC, ESE, Handy, KnowledgeTool, KEE, TQA, YES/MVS, TIRS, Integrated Reasoning Shell, GPSI, Neural Network Utility. Unfortunately, expert systems never really delivered on their promise, and their failure gave Artificial Intelligence (AI) a black eye in the business world. AI has been quietly used in many successful software products in the last few years, now that the processing power exists to actually make it work properly.

Export Language:  IBM’s expert system language used in TIRS.

Extended character:  A character other than a 7-bit ASCII character.

Extended Facilities Product:  z/OS and z/VM software, which IBM says is technically optional (not required for compatibility or operation), but is essential to unlock the total potential of the RAMAC Virtual Array Storage. Announced July 1996 and still available, even though the RAMAC Virtual Array Storage has been replaced by the 2105.

Extended License Charge:  See ELC.

Extended Memory:  Memory above the 1MB mark in an 80286/386 machine. Used in OS/2 and Windows/386 environments. Not much use in a DOS environment. Obsolete.

Extended storage:  An earlier term for what is now known as expanded storage.

Extensible Stylesheet Language:  See XSL.

Extent:  IBMspeak for a continuous space on a DASD volume occupied by a dataset or part of a dataset.

External Call Interface:  See CICS External Call Interface.

External Presentation Interface:  See CICS External Presentation Interface.

External Time Reference:  See ETR2.

Extranet:  A community of trading partners communicating via a controlled business network, using Internet communication protocols and Web browser technology.

Extreme Support Personalized:  See ESP2.

Extreme Support through Personalization:  See ESP2.

EZ-Prep:  Cross System Product/Application Generation. Feature of CSP1. PC software for customizing CSP programs to the PC environment. One licensed copy shipped with CSP/AD. Obsolete.

EZ-Run:  Cross System Product/Application Execution. Feature of CSP1. PC software providing a CSP run-time environment on the PC. One licensed copy shipped with CSP/AD. Obsolete. See also CSP/AE.

EZ Setup:  Software that walks you through OS/400 installation and customization. Part of iSeries Client Access Express. Shipped with all orders on the Setup and Operations CD-ROM.

EZ-VU:  PC product derived from mainframe ISPF, and used to provide a dialog development environment. Long obsolete.