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A glossary of terms important to IBM mainframe machines
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LAN: Local Area Network. A generic term for the transport mechanism for a local (e.g., site or building) network. The thing that makes current LANs special is their intimacy with the connected machines; effectively the LAN acts as an extension to the internal bus of the attached system, and allows a single system to be built from physically dispersed components.
LANACS: LAN Asynchronous Connection Server. Provides LAN access for ASCII terminals to IBM and ASCII hosts. Supports TRN, PC Network, IEEE 802.3, Ethernet, 3270 emulation, TCP/IP. Withdrawn January 1997.
LANAO/MVS: NetView software, announced December 1991, which provides some degree of automation for managing multiple distributed TRNs. Works by intercepting messages from LAN Network Manager and displaying important ones on a central operator’s console. In effect it’s a LAN version of ANO/MVS. Withdrawn June 1995.
LAN Distance: OS/2 and Windows remote access software. Enables an OS/2 or Windows workstation to dial in to resources on a remote LAN. Includes security through encryption and user ID verification. Can also be used to support portable computers as local office workstations. Replaced by OS/2 Warp Server and OS/2 Warp Connect April 1996.
LANDP: LAN Distributed Platform. Software that runs on Windows NT/2000/XP, OS/2 and PC-DOS, but uses a common API to provide access to a broad range of platforms, including CICS, IMS TM, DB2 and MQSeries. Evolved from the IBM Financial Branch System Services (FBSS) products.
LAN Emulation: Software provided with ATM2 adapters and some switches that enable ATM to be used with existing Network Operating Systems (e.g., NetWare) and applications that were developed for use with traditional LANs as opposed to ATM. Also, an ATM service of OSA-Express 155 that enables the reuse of the communications applications that were written to support Ethernet or Token Ring.
LAN File Services: IBM software used to store and share workstation-format files on z/OS and z/VM systems. Announced June 1993. The z/VM version replaced Workstation LAN File Services/VM and was withdrawn March 2000. cf. LANRES.
LAN Gateway: A function in the AnyNet product family that enables workstations residing in separate LANs to communicate across SNA or IP1 WANs. The AnyNet LAN Gateway supports both IPX and NetBIOS protocols across WANs.
LanguageAccess: End-user natural language interface for DB2. Works by translating a user request into SQL, which is passed to QMF, which digs up the data, and shows the answer to the eager querier. Written in Prolog, and integrated with QMF and AS1. Runs on OS/2 and interfaces to z/OS and z/VM. Withdrawn January 1993.
Language Environment: Arguably the most valuable long term result of SAA, LE provides a common runtime environment for major programming languages, especially on z/OS and z/VM where it is no longer a separate product, but has been absorbed into the operating system itself. The common library of runtime services includes message handling, condition handling, storage management routines and time/date functions. Previously, at least on the mainframe, multi-programming language applications were very tricky, if not impossible. IBM LE for VSE has its own program number, but is a VSE/ESA Base Program. On the iSeries 400, LE also became part of the operating system as ILE.
LANHOP/6000: LAN Home Office Program. Software, announced August 1993, which allows a remote workstation user to dial in to a pSeries gateway, which will in turn communicate with the user’s workstation on a LAN, thereby preventing him or her from ever getting away from work. Supports OS/2, DOS, and AIX remote workstations, and there’s z/VM and z/OS access too. Withdrawn January 1996, though the then-IBM Global Information Network offered the equivalent through Dial Services for TCP/IP.
LAN Management Utilities: AIX and OS/2 product for system management of PC LAN and Novell environments from a NetView management AIX or OS/2 workstation. Provides central monitoring and problem resolution for systems running IPX, IP1, and NetBIOS protocols. Both versions withdrawn mid-1997.
LAN Manager1: IBM PC program for collecting problem, status, and diagnostic information from a Token Ring or PC network – a LAN equivalent of NetView. The OS/2 version was re-named LAN Network Manager September 1990.
LAN Manager2: OS/2 LAN software from Microsoft developed in conjunction with 3Com. Provides client/server support for distributed applications across a network. Facilities include file and printer sharing, security, and network administration. Originally, LAN Manager was very intimately bound into OS/2 and used all the clever bits of OS/2 (particularly the inter-process communication) to produce a high-performance, full-featured LAN operating system. However, when Microsoft reduced its involvement with OS/2, LAN Manager became a discrete set of services capable of running with any operating system. It’s not a bad workgroup solution, but not that good as an enterprise solution, where IBM’s LAN Server (which started life as LAN Manager) is a better bet. Obsolete, its functionality now being part of Windows Server operating systems.
LAN NetView: Suite of OS/2 LAN network management software announced October 1993. Provided remote support of OS/2 LAN software using the CID standards, performance management, problem determination using both CMIP1 and SNMP, asset management and inventory control, and links to the mainframe by translating OSI alerts into SNA alerts. September 1994, LAN NetView became NetView for OS/2, then Tivoli NetView in July 1997.
LAN Network Manager: AIX and OS/2 LAN management tool. It’s a September 1990 re-naming of IBM’s LAN Manager1. LAN Network Manager collects information about the physical layer of a LAN – cabling, access units, hubs, bridges, and network adapters, etc. The software can also collect SNMP information from software (LAN Network Manager Agents) in bridges to other connected LANs. Features include CUA1 interface, two-way NetView communications, LAN Station Manager support, and a database of the LAN and its workstations. LAN Network Manager Entry is a stripped down version without a local operator interface – it just relays information from a remote LAN to a central operator. The AIX1 version became part of SystemView then was replaced by Nways Campus Manager-LAN for AIX in September 1996. The OS/2 version was withdrawn September 2000.
LAN Network Manager Agent: Software in a TRN bridge which collects information about a LAN and relays it back to a LAN Network Manager station. Note that not all bridges can act as agents, although the IBM bridges can. Obsolete.
LANRES: LAN Resource Extension and Services. z/OS, z/VM and OS/400 software that allows a mainframe or iSeries 400 to act as a host server for NetWare servers – i.e., NetWare clients can access host-attached printers and disk volumes. It also allows NetWare LANs to be administered from a mainframe. Announced as an RPQ for z/VM in May 1991 (a program product from September 1991), as an z/OS product in September 1991, and on the iSeries 4000 late 1993. A significant product for DP managers, since it offers some prospect of DP proving to all the users of those LAN-based systems that there’s still a role for the professional data center. cf. LAN File Services. Obsolete.
LAN Server: When announced in November 1987, a network server providing LAN services for DOS, Windows, and OS/2 under OS/2. Non-dedicated – i.e., other tasks may run in the same LAN Server machine. Facilities include print and file services, centralized network administration, access to and management of shared resources, and multiple servers. It was originally based on Microsoft’s LAN Manager2 (which IBM licensed for use in OS/2 EE) with IBM bells and whistles to suit it for the enterprise environment. Version 3.0 (October 1992) was a full 32-bit implementation with a few extra functions, and in September 1994 Entry and Advanced versions were announced. Replaced by OS/2 Warp Server December 1996. Over the years, LAN Server has been announced for many other platforms. An OS/400 version. An AIX version was replaced by AIX Connections in November 1996. A z/OS version was announced in March 1995, enabling the mainframe to act as a server for OS/2 LAN Servers. And then there was LAN Server for Macintosh, which was OS/2 software which allows Macintosh users to send files to Postscript printers on an OS/2 network, and PC users to access printers on an AppleTalk network; withdrawn August 2000. LAN Server Ultimedia was OS/2 software that allowed a number of users to simultaneously access full motion video and sound from a single LAN server; announced November 1993, withdrawn December 1997.
LAN Station Manager: PC-DOS and OS/2 program which collects information about a workstation (adapter, office number, etc) and transmits it to LAN Network Manager. Uses the ISO CMIP (see CMIP1). Announced September 1990, withdrawn July 1997.
Laptop: Generic term for the first generation of portable computers that were small enough to use on your lap without cutting off the blood supply to your toes.
Large Program Support: Replaced by Very Large Program Support.
Latency: A measure of response time. On a disk drive, how long it takes for the first bit of requested data to rotate under the head. In a network, the minimum elapsed time for a message to be transmitted, consisting of the aggregate delay contributed by the communications links and devices along the way. For a computer, the time period between the issuing of a command and the beginning of the requested action. At McDonalds, how long it takes your hamburger to arrive after you order it.
LCAP: Loosely Coupled Array Processors. An IBM parallel processing research system in the late 1980s which linked 3090-400s and -600s into a single system.
LCD: Liquid Crystal Display. Technology used in calculators and, more recently, laptop computers. Originally monochrome only, but TFT provides a color technology used in laptops, replacing CRTs in desktop monitors and perhaps televisions in the future.
LDAP: Lightweight Directory Access Protocol. An Internet directory management standard that provides a consistent way to manage user access to network resources, such as information, applications, and systems.
Learning Services: The part of IBM that lets them lay claim to being world’s largest computer training company.
Leased line: Generic term for a wide area communications line that is always available to the user – i.e., it is not shared, and it is not interruptible. Such lines are usually rented from a PTT – hence the name. See Switched line.
LED: Light-Emitting Diode.
Legacy system: An old system, running on incompatible hardware, and probably unsupportable because the code is unstructured and the guy who wrote it left to become a Buddhist priest some years ago. Legacy systems are the bane of the DP manager’s life. IBM sometimes uses the term in a slightly different way, to mean part of an open system that belongs neither to the SAA camp nor to Unix (and which is thus thoroughly undesirable). See also New World system.
LEN node: Low Entry Networking Node. A type 2.1 node which doesn’t have the APPN extensions to the LEN architecture. A LEN node can take part in an APPN network but only as an origin or destination node, not as a network node.
Lexmark: The Lexington, Kentucky company (an IBM alliance company) into which IBM put its keyboard, typewriter, and low-end printer business in 1990. IBM retained 10% of the equity in Lexmark, which did a lot better after it left IBM than it was doing when it was part of IBM (it doubled profits in the first two years of independence). It still supplied lots of machines and consumables to IBM, both under its own name and as an OEM supplier, until the expiry in March 1996 of a non-competition agreement. IBM then got into the business in a big way, including a paper line in stores everywhere. See also Network Printer, Pennant.
LI: License Information.
libpcap: Packet Capture Library. A high-level user interface to the Berkeley Packet Filter (BPF). Plus an API with the BPF for reading unprocessed network traffic and writing customized applications that monitor and/or capture the network traffic.
Library Readers: BookManager software included on the IBM manual CD-ROMs that allows the reading of the manuals.
LIC1: Licensed Internal Code. IBMspeak for microcode. When you buy an eserver zSeries 900 or iSeries 400, you buy a license to use the microcode supplied with the machine. If you mess about with the microcode IBM can, and sometimes does, descend on you with lawsuits (see AMI2). See also SLIC.
License Manager: IBM License Manager. z/OS tool used by IBM to implement WLC. It also allows vendors to enable their products for licensed software management by customers. ILM is based on Version 2 of the X-Open Software License Manager (XSLM) standard from The Open Group, which defines a software license use management system. See also ILM Management Tool.
LIFO: Last In, First Out. A queuing technique where the most recent addition to the queue is processed first. Also known as a push-down stack. cf. FIFO.
Linda: A groundbreaking mid 1980s research system developed by David Gelernter and others at Yale University.
Line of Business: The things a company does to earn its living – e.g., banking, manufacturing, etc. Also used to refer to an organizational unit within a decentralized corporate structure. Within IBM, a Line of Business is a group of product divisions.
Linkage Editor: Program which converts an object code module into an executable load module. It may also include external subprograms, and perform various operations on load modules. In z/OS, the Linkage Editor has been replaced by the Program Management Binder.
Link test: A test used in SNA to test the operation of links. Three types of test can be carried out, differing in the resources deployed, but all are based on one link station returning unchanged the data received from another link station.
Linkway: Application development language on the PC that allows you to develop applications using text, pictures, sound, video. Withdrawn October 1997.
LINPAK: A benchmark for scientific systems. Developed by the Argonne National Laboratory in the USA. Widely quoted by IBM (cf. RAMP-C). LINPAK measures the speed with which a system solves sets of linear equations.
Linux: A Unix variant that seems to run on everything from workstations, where Microsoft haters insist it will replace Windows, to mainframes, where IBM has spent bags of money making it run well. Linux runs on all four eserver families. It can be run native or in an LPAR on the zSeries 900. xSeries offers an option for preinstalled Linux distributions. The iSeries 400 supports the native Linux kernel in an OS/400 partition. And pSeries supports native PowerPC Linux distributions. There are 12 Linux Porting Centers worldwide that provide IBM technical assistance to ISVs and applications developers that are moving to Linux.
Lion food: IBMspeak for middle management – after a not very funny joke about a lion which hid near an IBM office and got away with eating an IBM manager every day for a year, because nobody noticed what it was doing.
LISP: Development language and application environment for artificial intelligence and expert systems. Available on z/VM, z/OS, PC, and AIX. Key IBM implementation was Common LISP which used PCs connected to an z/OS mainframe to provide a full LISP environment. Long gone, except for an RT PC version of LISP discovered in the Year 2000 efforts, and promptly withdrawn December 1997. See also Golden and LUCID.
LL2: Link Level 2.
LLAPI: Low-Level Language Application Programming Interface. PC Macro Assembler interface. Allows user written programs to simulate a terminal operator. Note that the term is also used generically, and that everybody’s LLAPI is different from everybody else’s.
LLC: Logical Link Control. An IEEE standard for LANs and WANs, implemented and enhanced by IBM and other vendors, which defines how command packets (protocol data units) are created and interpreted for supporting logical link functions. Provides a common access control standard and governs the assembly of data packets between workstations, regardless of how the packets are transmitted across the LAN (i.e., it doesn’t determine how the transmission medium is shared).
LoadLeveler: An AIX1 workload management system for serial and parallel batch jobs. Several methods of scheduling jobs, including the availability of a specified resource. Uses PSSP Security Services within DCE2.
Load module: A program in a form that can be loaded into memory for immediate execution.
Location transparency: Generic term most widely used with reference to distributed database. In a system which has location transparency, the user cannot tell which of any connected systems he is communicating with. For example, the response time, user request, etc, would be the same for remote access as for local access.
Logical Partitioning: Way of dividing up a processor’s capacity under PR/SM into LPARs (Logical PARtitions). Available on eserver zSeries 900 and iSeries 400. New with the zSeries 900 was the ability of products and programs running in an LPAR to query a unique identifier and the capacity for the LPAR, giving the LPAR the properties of a virtual server. This gives ISVs the option of licensing their software to an LPAR, and thus an additional method of implementing sub-CEC pricing.
Logical String Assist: Firmware first added to the ES/9000 (9021 and some 9121s) to improve performance of C and other high-level language applications which perform extensive string manipulation operations.
Logical Volume Manager: The set of AIX operating system commands, library subroutines and other tools used to map data between a logical view of storage space and the actual physical disks. The logical volume device driver (LVDD) is a pseudo-device driver that manages and processes all I/O.
Logos Machine Translation: Software to assist translation between languages, such as English to Italian, from Logos Corporation. Marketed by IBM.
Lone Star: The IBM codename for its first copper-based microprocessor, released in September 1998.
Loop adapter: A component of the 43xx processor family that enables a variety of SNA and non-SNA devices to be attached. A few subsequent but unrelated devices with the same name have been available over the years.
Lotus: A very independent part of IBM. Originally a PC software company made rich and famous by 1-2-3, which took over from where the first spreadsheet, VisiCalc, left off. IBM set up a strategic software alliance with Lotus in June 1991, which allowed IBM to market the cc:Mail electronic mail system and Lotus Notes groupware product for interactive file and data sharing across a LAN. June 1995 IBM bought out Lotus in a transaction which started as a contested takeover, and then became uncontested when IBM offered so much money (a premium of around 100% on the quoted share price), that the shareholders couldn’t resist. IBM’s aim, according to observers, was to get its hot, sticky hands on Notes and cc:Mail (which it had been distributing for four years), and the Notes customer base. Wisely, Lotus corporate culture was retained and the company flourishes inside IBM. Note: within this glossary, Lotus products and services are, like IBM’s, listed without Lotus in front of them.
Lotus Web Content Management Solution: A combination of products, business consulting and Lotus Professional Services designed to deliver a customized Web content management solution. Announced October 2001.
LOVEM: Line Of Visibility Enterprise Modeling. An IBM trademark and methodology to define and document the activities in a business process, particularly for workflow solutions. The obsolete Business Process Modeler was built on LOVEM.
LPA: Link Pack Area. The z/OS area used for resident programs, e.g., those programs which are most frequently used and (usually for performance reasons) should not be loaded by each application program from libraries stored on disk.
LPDA1: Link Problem Determination Application. Application software within NCP that gathers information from IBM modems and other DTEs about the common carrier transmissions – noise, carrier drop-outs, etc. A version of LPDA is also available on the iSeries 400 where it supports the use of the iSeries 400 as the middle tier of a three-tier system.
LPDA-2: The second version of the Link Problem Determination Aid (LPDA2) command set. In addition to the functionality of LPDA-1; LPDA-2 also supports the following commands: DCE2 configuration, dial and set transmit speed.
LPT: Line PrinTer. Used in the LPT: logical device name on PC-DOS and Windows operating systems for the default printer.
LRA: Local Registration Authority.
LRU: Least Recently Used. Generic (non-IBM) term referring to the selection of items from a group based on when they were last accessed. Typically used in archiving and virtual storage management. For example, when you run out of real memory, it makes sense to page out the blocks of memory that were least recently used.
LSA: Local Security Authority.
LSPR: Large Systems Performance Reference. An IBM methodology for comparing the performance of IBM and compatible mainframes. The apparently deliberate leakage of the LSPR in mid 1991 caused something of a storm in a teacup (it was leaked in England). February 1993, IBM decided to publish the whole lot. It doesn’t seem to have hurt, since IBM is still using LSPR to rate their mainframes.
LTERM: Logical TERMinal. IMS TM terminology.
LTLW: LAN-to-LAN Wide area network program. OS/2 software for connecting LANs. Supports NetBIOS, TCP/IP, and IPX. Also runs within the 8250. An entry level version was announced January 1993. Withdrawn August 1998.
LU: Logical Unit. The user’s port into an SNA network. LU1 is a high performance print stream, LU2 is a 3270 datastream, LU3 is a 3270 print datastream. LU6 is a Logical Unit to allow host-to-host data exchange. LU7 is the 5250 datastream. LU6.2 is the most exciting LU and gets an entry all of its very own in this glossary. See also BIND1, Independent LU.
LU6.2: Peer-to-peer datastream cum network operating system for program-to-program communication (see APPC), which allows machines to talk to one another without the involvement of the mainframe. LU6.2 also supports asynchronous (store-and-forward) networking. LU6.2 is IBM’s strategic device-independent, process-to-process protocol.
LUCB: Logical Unit Control Block.
LUCID: Obsolete LISP implementation under AIX.
Lunatic fringe: IBMspeak for customers who can always be relied upon to take the first release of new software.
LX: Long wavelength.