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A glossary of terms important to IBM mainframe machines
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P/370: Version of the PC capable of running 370 code and the z/VM CMS1 timesharing system. Sank without much trace. The concept was resurrected in the 7437 technical workstation, which went the way of its predecessor. Never one to give up, IBM optimistically launched the PC Server 500 System/390 in mid 1995.
P76: IBM color monitor announced September 1999.
P96: IBM color monitor announced January 2000.
PABX: Private Automatic Branch eXchange. An in-house (telephone) exchange, usually just for voice, but increasingly for data too. IBM PABX products included the 1750/3750, Com300, and 8750/97501, but these days, IBM is out of the market.
PacBase: Set of integrated CASE1 products from CGI Informatique. Has its own repository, which works in mainframe and LAN environments. Includes the PacDesign requirements analysis and system design tool; the PacBench and Pac/CS generation and maintenance tools; and the PacRevers reverse engineering tool. Supports a wide variety of vendor platforms, and can provide a common development tool that can be used to develop client/server, on-line, and batch applications in multivendor environments. See VisualAge PacBase.
Pacing: Generic and SNA-specific term for a communications technique in which receiving equipment controls the rate at which the sending station transmits to ensure that data is transmitted through a network at a rate (pace) not exceeding the capacity of the receiver to store or process the data. Adaptive pacing is a facility available with LU6.2 whereby the system automatically adjusts the rate of flow of data through the system according to the prevailing conditions.
Packet: The basic transmission unit in packet switching systems. Typically it contains data, together with control and routing information telling the network where the data is to be sent. A good analogy is the envelope plus contents in a conventional postal system.
Packet switching: Generic term for a way of transmitting data through a network. The data is wrapped up in a packet together with control and routing information telling the network where the data is to be sent. In a conventional circuit switched system, a continuous connection is made between sender and recipient; in packet switched systems, no such connection is needed – the connection need only exist for long enough and far enough for the packet to get to the next network node which stores the message, reads the address and forwards the message and address to the next node, and so on. Because of the way it works, traditional packet-switching is not very good for voice traffic. For years IBM was somewhat dismissive about packet switching, but later became fairly enthusiastic. See also Frame Relay, Cell relay, Fast packet.
PAD: Packet Assembler/Disassembler. Device on the edge of a packet switching network to convert between packetized and non-packet (e.g., start-stop or BSC) datastreams. In effect, the PAD collects single characters from the terminal and assembles them into packets. On delivery the remote PAD or user software reverses the process.
Page: An essential process within virtual storage technology. Fixed sized blocks (typically 4096 bytes) of memory are freed up by writing their contents to a paging device until any virtual address within that block is referenced. cf. swapping.
Paging device: Storage used to store virtual storage pages that cannot currently be accommodated in real memory. Typically DASD, especially now that DASD controllers have significant amounts of cache memory, but drums and fixed head disk have been used in the past to provide the performance required.
PAL: Phase Alternation Line. One of three incompatible analog television display and video tape recording standards. The other two are NTSC and SECAM. The UK and most of Western Europe uses PAL, North America and Japan NTSC and France SECAM.
Palm PC: Rumored (mid 1996) IBM PDA with Web browsing capabilities. Eventually materialized as the WorkPad (8602) in September 1997. Not to be confused with Palm, Inc., a big player in the PDA market.
PAN: Personal Area Network. Developed at IBM’s Almaden Research Center, PAN taps into the human body’s natural electrical conductivity to transmit electronic data. People equipped with PAN transmitters can exchange simple data such as business card information with a handshake. PAN has ramifications for corporate security. When users equipped with PAN devices walk away from their PCs, the machines could automatically log them off, then log them on again when they detect the user’s PAN signal: increasing levels of security without requiring extra steps by users. Yet to come out of the lab.
Panel: IBMspeak for screen layout.
Paradyne: Company bought by AT&T in 1989 which specialized in channel extenders. July 1991, Paradyne and IBM announced that they were to cooperate on developing channel extension technology to enable ESCON to work at T3 rates over LANs and WANs. In June 1996 AT&T sold Paradyne for around 75% of what it paid for the company seven years earlier.
Parallan: Manufacturer of high-end multiprocessor LAN servers. IBM set up a development agreement with Parallan in 1992, and sold the Parallan machines as superservers (PS/2 195/295). June 1994, the agreement lapsed.
Parallel processing: Generic term for systems which have many processors (CPUs) which do loads of things at once. IBM has lots of laboratory parallel processing systems (Arbre, Eden, Mach, PPCS, RP3), and some products (Parallel Query Server, Parallel Transaction Server, Power Visualization System, SP1, SP2, VAST-2). And the parallel sysplex began as a way to process as much work with CMOS by using several cheaper CMOS processors in parallel, rather than one expensive fast bi-polar processor. Today, bi-polar is dead and CMOS is fast enough, but parallel sysplex is a good idea that survived. Historically, Amdahl’s first PCMs, in the mid 1970s, were parallel, using a pipelining technique where up to 10 machine instructions were each in different stages of execution at any given moment in time. Gene Amdahl used this approach to give him speed without needing IBM’s R&D budget for the fastest, newest technology. See also HIPPI, HPCS, HPSS, LCAP, PPCS, Supercomputer, Virtual coupling.
Parallel Query Server: z/OS DB2 database query system (at one time known as the HPQS – High Performance Query System), consisting of multiple parallel System/390-based CMOS microprocessors (the same design as is used in the Parallel Transaction Server) and query software. Much pre-announced during 1993, and formally launched in April 1994 as the 9673. Mainly targeted at EIS2 and data mining type operations rather than production data processing. The PQS was not a great success and was withdrawn May 1998. See also PPCS.
Parallel sysplex: Architecture cum bundle of products announced April 1994 which allows parallel transaction processing in an ES/9000 sysplex. Provides resource sharing, workload balancing and continuous availability. Initially supported up to 32 z/OS systems, presenting them as a single systems image known as a cluster4. Major hardware pieces are the Coupling Facility, Sysplex Timer and links to them both. CICS and IMS TM are just two of the software products that needed changes. More recent software has been developed with parallel sysplex in mind, including IRD, Coupling Facility Structure Sizer Tool and the Web-based Parallel Sysplex Configuration Assistant that sets up the initial JCL, procedures and parameters for parallel sysplex. Most parallel sysplexes begin as a single system cluster, with all the parallel sysplex pieces in place. More recently, the architecture has been expanded into the Geographically Dispersed Parallel Sysplex (GDPS). See also CICSplex, ClusterProven.
Parallel Transaction Server: New System/390 architecture pre-announced (in a rather half-hearted way) October 1993, and formally announced in April 1994 as the 9672. Comprises multiple CMOS System/390 microprocessors and OS/2 systems connected (within a single box) via fiber-optic links, sharing a common DASD subsystem, and presenting a single system image. Frequently accessed data is held in a shared cache with locking mechanisms to mediate access. Dynamic workload re-balancing occurs when processors are brought on- or off-line (whether intentionally or because of failure). It’s able to provide continuous support for CICS, IMS TM, and IMS DB (DB2 is promised). Extra microprocessors can be added incrementally to give a 40-fold growth capability. Renamed Parallel Enterprise Server in September 1994 and replaced in October 2000 by the eserver zSeries 900. See also CICSplex, Coupling, Parallel Query Server, parallel sysplex.
Parallel Visual Explorer: IBM Parallel Visual Explorer for AIX1. Software (announced December 1994) for the parallel RS/6000s which detects patterns and relationships in large databases with many variables. Users manipulate polygonal lines representing relationships. IBM proudly claimed at the launch that it is understood to have no known competition. Withdrawn March 1998.
Parity bit: A binary digit check bit appended to a group of binary digits to make the sum of all the digits, including the appended binary digit, even or odd, depending on whether Even or Odd Parity is being used.
Parmlib: Parameter Library. A dataset in z/OS containing parameter settings. The most important is SYS1.PARMLIB which contains parameter settings for z/OS and many key subsystems.
Parse: The analysis of the operands entered with a command in addition to the creation of a parameter list for the command processor. It can also refer to the initial processing of source code by a compiler, when it divides up each program statement into its component parts, also known as tokens. Hence, the term tokenization.
Parthenon: IBMspeak for the graphic showing the structure of SAA, without which any IBM presentation between 1987 and 1992 was incomplete. Frankly it bore a much closer resemblance to the altogether more pagan Stonehenge, except that it wasn’t as well designed, and didn’t last as long.
Partition2: In DB2, a dataset which makes up part or all of a tablespace or indexspace. Until March 1993, partitions were highly interdependent – if you wanted to do maintenance work on one partition, all the other partitions of the tablespace were locked out. The March 1993 announcements changed this, enabling people to work on lots of partitions at the same time, which improved availability and paved the way for parallel searching of different partitions within a tablespace.
PAS1: Primary Address Space. The address space which contains the executable code (and may also contain data). First used in ESA environments where multiple 2GB address spaces, the maximum size accessible in 31-bit addressing (see AMODE), are being used in a single program. Access registers are used to indicate which address space is being referred to.
PassTicket: A dynamically generated, random, one-time-use, password substitute, used in RACF, that a workstation or other client can use to sign on to the host rather than sending a RACF password across the network.
Password: A string of characters, intended to be kept secret, that a user enters with his user ID to confirm his/her identity.
Patch: A code modification, to correct a reported problem, that is sent to software product users after the release of a product.
PAV: Parallel Access Volumes.
pax: AIX archiving utility.
Payment Gateway: Member of the IBM Payment family which implements the SET protocol. Payment Gateway provides an intelligent router function for SET transactions and transactions received over the SSL communications link. It is used as a place to tailor messages as they are being routed so that the receiving transaction system does not require changes. There are z/OS and AIX1 versions.
PC: Personal Computer. IBM’s family of microcomputers. The announcement of the PS/2 in April 1987 appeared at the time to have relegated the PC to obsolescence. The name re-emerged in October 1994 when IBM rationalized its PC nomenclature. See also PC Server.
PC/3270: Personal Communications/3270. Not be confused with the 3270 PC, PC/3270 is a PC-DOS, Windows, and OS/2 Communications Manager program (first announced May 1989 with the OfficeVision products). Provides multiple 3270 sessions, emulator HLLAPI, ability to connect to multiple mainframes as a 3270 terminal or workstation printer, and to act as a generic LAN gateway. Includes support for IPX/SPX, TCP/IP, and remote async connection. Replaces the IBM 3270 Emulator Program. 32-bit implementations announced February 1995. After a long string of replacements and renamings, its current replacement is IBM Host Access Client Package for Multiplatform.
PC/AT: Model of the PC, announced in September 1984 which used the Intel 80286 processor. The bus on the PC/AT was the most advanced of the buses on the original PCs, and is the basis of the ISA and EISA standards. Obsolete.
PC/XT: Obsolete PC.
PC-DOS: Operating system for the IBM PC. A specific (IBM proprietary) implementation of MS-DOS. Essentially it is MS-DOS’s BDOS with an IBM extended BIOS. To all intents and purposes, MS- and PC-DOS were identical, until late 1992 when IBM bundled data compression and memory management features into Version 5.0, making the two DOSs different. PC DOS 2000 is still available, although support ended January 2001. It is PC-DOS Version 7 with Year 2000 support. See also DR-DOS.
PCDU: Power and Coolant Distribution Unit.
PCF: Primary Control Field.
PCI: Peripheral Component Interconnect. Extremely popular PC bus standard originally promoted by Intel and soon supported by IBM, even though it meant dropping its beloved MCA. So far, the only defections have been video cards, which have switched to AGP. PCI is certainly not restricted to PCs. Witness the PCICC in the eserver zSeries 900.
PC LAN Program: IBM PC LAN server system (PCLP) based on Microsoft’s first network product, MS-Net (1983). Never a great success – it was memory hungry, slow, difficult to administer, etc. In a greatly enhanced form, PCLP became OS/2 LAN Manager2.
PCM: Plug Compatible Manufacturer. A manufacturer who makes hardware that can just plug into an IBM configuration. PCMs make mainframe processors, DASD, tapes, printers, terminals, FEPs, PCs and just about all other equipment that you might find in an IBM network. Typically the PCMs sell on price/performance. Some sell technical innovation too (e.g., smaller form-factor DASD, operating system add-ons, etc), but the need to maintain compatibility severely constrains them in this area. PCMs have included Amdahl, Andor, Commercial Data Servers, Comparex, Fujitsu, HDS, Hitachi, Memorex Telex, Storage Technology Corp, Nixdorf, and Elbit. IBM uses the term SCV synonymously with PCM. See also VM/MPI for an interesting twist to the PCM tale.
PCMCIA: Personal Computer Memory Card International Association. Industry-standard interface (not just for memory, but for modems, network interfaces, etc) for laptop and notebook computers, including the popular IBM ThinkPad. PCMCIA cards sell at a large premium compared to their desktop, typically PCI, equivalent.
PCM lag: The length of time it takes the mainframe PCM suppliers to implement new IBM features on their machines. On average it’s about a year – more for difficult features, but rarely more than 18 months.
PC Network: Defunct low cost local area network (LAN) for PCs which used a single CSMA/CD channel over standard broadband CATV cable. The technology was not IBM-originated but based on Sytek products. Obsoleted by the TRN. Its protocols live on in the SMB standard.
PCO: PCO, Inc. Formerly a company belonging to Corning Glass, which owned lots of high tech patents in the opto-electronic field. IBM bought 25% of PCO in January 1989 with the aim of building a new IBM LAN based on the FDDI standard.
PCradio: Ruggedized, A4-size, lightweight PC-DOS PC with options for communicating over cellular networks. Announced August 1991 on a special bid basis, and became a product-line product mid 1992. It didn’t seem to strike a chord in the marketplace, it was withdrawn August 1993, and by April 1994 all rights had been sold to the Aspen Marine Group in Florida.
PC RT: A common misnomer for the RT PC (6150) which IBM chose to name in a way quite inconsistent with the way it named its other PCs. Maybe that’s why so few people bought it. Finally withdrawn May 1991.
PC Server 500 System/390: PC – aka P/390 – announced mid 1995 which, with the aid of an extra card, can run a full System/390 system. March 1996, the thing acquired a raft of 390 features, including support for ECKD, 3390, triple density 3380, 9345, and 3350/3330; enhanced SDLC1 and bisync communications for z/VM and VSE/ESA; 3172 SDLC1 Gateway for z/OS; multiple SCSI tape; performance enhancements relating to the execution of decimal instructions; support of I/O assist in z/VM; and some shortened I/O ESA path lengths. Withdrawn with effect from August 1996 with a promise of a replacement sold through business partners. Still software supported with z/VM listing it in its October 2000 announcement. See also R/390, P/370, NUMA-Q.
PC Support: Package of software on PCs (OS/2, PC-DOS, and Windows) and mid-range machines, enabling PCs to communicate with a System/3x or AS/400. A well-regarded package in terms of facilities and functionality. Includes support for APPN, NetWare, AFPDS, and IPDS. Replaced by Client Access/400 mid 1995.
PCTE: Portable Common Tools Environment. An ECMA standard (interface specifications) for CASE1 environments. Popular when it first came out in both Unix and AIX1 products, and ECMA has continued to make improvements to it over the years.
PDA: Personal Digital Assistant. Generic term for hand-held devices that range from electronic organizers to a PC stand-in, some also serving as cell phones. Matured around the turn of the century, after spending the 1990s as an even more expensive, and even less useful, electronic version of the grotesquely overpriced and functionally challenged personal organizers without which no yuppie (or IBM salesman) was complete in the 1980s. Vendors include Palm, IBM, Kyocera, Handspring, Sony, Compaq, Casio, HP and Xircom. IBM’s major offering is the Palm-compatible WorkPad family (8602), though the ThinkPad 240 (2609) proved small enough to replace the WorkPad z50 (2608). See also Simon.
PDL: Page Description Language. Generic name for languages used to describe page layout. Roughly, the process is that the word processor or other software produces a stream of PDL, which it sends to a smart printer, which then processes the PDL statements to create the specific commands to drive the print engine. IBM uses PostScript and IPDS as PDLs.
PDM: Programming Development Manager. List-driven application development environment for the iSeries 400. Other application development tools are called from PDM which maintains libraries and navigates through other application development components (SEU, SDA, DFU). It appears to be a re-birth of the System/36 POP1 (Programmer and Operator Productivity) PRPQ2 tool, which IBM never liked very much. Now part of ADTS.
PDN: Public Data Network.
PDO: Product Delivery Offering.
PDS1: Partitioned DataSet. A z/OS dataset1 that is really datasets within a dataset. Each PDS is made up of zero or more members. Each member has all the characteristics of a standard sequential dataset, though all members share the same attributes: those that were defined for the PDS when it was allocated. Each member has a one to eight character name that follows the same rules as a level of a standard z/OS dataset name (DSN). Each PDS has a directory of its members, which can also (optionally) contain other information, known as Statistics, which are maintained by software such as the ISPF/PDF editor. Last modification date is an example of a Statistic maintained for each member. Members can be added, deleted or replaced at will, but space is not automatically recovered. The result of repeated changes to a single member can result in a very large PDS or even failure if the PDS cannot expand any more. Individual members can be treated as sequential datasets, but the BPAM access method is available for direct processing of the PDS and its directory. See also PDSE.
PDS3: Personal Printer DataStream.
PDS4: Personal Dictation System.
PDSE: Partitioned DataSet Extended. Despite being introduced October 3, 1989, in an attempt to address the limitations of the PDS1, the vast majority of the world’s PDS are still PDS, not PDSE. PDSE recovers space whenever a member is deleted or replaced/updated, but it cannot contain load modules and must be located on an DFSMS-managed volume. 11 years later, Tivoli Data Exchange seems curiously out of touch by supporting PDSE and not PDS.
PE: Parallel Environment products.
Peer-to-peer: A form of distributed system in which all participating nodes can function as both client and server. Loosely, refers to systems like SETIathome, in which PCs act as servers and a large Unix machine is the client.
Pegasus1: Symmetric multiprocessing (SMP) version of the RS/6000 announced October 1994. Pegasus was a joint development with Bull. Obsolete.
Penalty Box: A non-job into which an IBMer has been maneuvered. Similar in nature to the Parking Lot in that there is the possibility to move out after good behavior. See also Cemetery, Cooling house, ROJ.
PenDOS: Extension to PC-DOS which let users access programs and operating system functions using a pen instead of a mouse or keyboard. Included handwriting recognition, soft keyboard data entry, and mouse emulation. Announced May 1994. Withdrawn December 1997, but support ended in June 1995. See also Pen for OS/2.
Pen for OS/2: Extension to OS/2 Version 2.1 which let users access programs and operating system functions using a pen instead of a mouse or keyboard. Included handwriting recognition and soft keyboard data entry. Announced May 1994. Withdrawn December 1997, but support ended in June 1995. See also PenDOS.
Penguin: IBMspeak for the old-fashioned field support engineer who always used to wear a dark suit and white shirt, and to carry such a heavy toolkit that he waddled.
Pennant: Company formed during IBM’s massive December 1991 re-organization to handle the high-end printer market – hardware and software. Like other subsidiary companies, Lou Gerstner brought Pennant back into IBM shortly after his arrival. See also Lexmark.
PenPoint: System from Go Corp which provided a pen-based operating environment. IBM licensed the PenPoint technology in 1990, which it favored over Microsoft’s rival Pen Windows environment.
Pentium: Intel’s successor chip to the 486. Until release, it had been referred to as the 586, and the Pent in the name reflects that fact. Pent is from the Greek for Five and is used in words like pentagon in English. Pentium chips started dribbling out onto the market in May 1993, followed by bulk shipments in the second half of 1993. IBM gave up its right to manufacture Pentiums in February 1994, pinning all its hopes on the PowerPC, although it provided a wide range of Pentium-based commercial and SoHo machines using the thing. Replaced by the Pentium II and Pentium Pro.
Pentium 4: The Intel replacement for the Pentium III, and a retirement of Roman numerals in the product name. Introduced in 2000 with 1.3-1.8GHz processors and a system bus that is three times faster: 400MHz compared to 133MHz for the fastest Pentium III. Uses 0.18 micron circuit lines with 42 million transistors on the chip.
Pentium II: Intel’s successor to the original Pentium. Introduced in 1997, it incorporated MMX technology and dual bus architecture, with one bus linked to the L2 cache and the other dedicated to the main memory. This allowed the processor to access data simultaneously or in parallel rather than in a single sequential manner. The Pentium II is actually a version of the earlier Pentium Pro, with support added for 16-bit applications; the Pentium Pro was designed for Windows NT, which only supports 32-bit applications. All this required 7.5 million transistors on the chip. Replaced by the Pentium III.
Pentium III: Intel processor using 0.25 micron technology. The replacement for the Pentium II also had a low end version called the Celeron. Introduced in 1999 with 9.5 million transistors and 70 new machine instructions. Dropping the Roman numerals, the Pentium 4 replaced the III in 2001, most notably with a system bus that was three times faster. At the same time, 133MHz memory, the fastest system bus speed offered on Pentium III, suddenly dropped dramatically in price.
Pentium Pro: An Intel 32-bit processor designed for Windows NT (NT cannot run 16-bit applications). Introduced in late 1995, the chip contained 5.5 million transistors. See also Pentium, Pentium II, Pentium III.
PEP: Partitioned Emulation Program. Software resident in the FEP supporting co-existence of EP and NCP operations in a single processor, thereby enabling a communication controller to operate some lines in network control mode, while simultaneously operating others in emulation mode. Useful in a mixed host environment where SNA and non-SNA access methods are in use at the same time.
Performance Reporter: IBM Performance Reporter for MVS, TME 10 Performance Reporter for OS/390, and Tivoli Performance Reporter for OS/390. All names at one time or another for what is now Tivoli Decision Support for z/OS.
PERL: Practical Extraction and Reporting Language. A general purpose Unix scripting language which is popular for writing CGI programs. Its speed and flexibility make it well suited for form processing and on-the-fly page creation.
Persistence: Emulation of an end-to-end connection over IP1, as in an SNA session, to ensure client/server integrity and security in Web-to-host access scenarios (in particular, browser-to-host schemes) given that HTTP per se is a connectionless protocol.
Persistent verification: A VTAM sign-on/sign-off capability between two LUs that transmits a password only once, during sign-on, rather than on each attach. Particularly useful in CICS cooperative processing applications.
Personal Application System: PS/2 version of the mainframe AS1 system announced October 1988, and also known as Personal Application System/2, PAS, AS/2, SAA Personal Application System/2, Personal AS, Personal AS for Windows, or IBM Personal Application System/DOS for Windows. Bearing in mind mainframe AS’s capacity for bringing 3090s to their knees, Personal AS had to be approached with caution. Withdrawn May 1998.
Personal Communications: A family of IBM software that emulates 3270 and 5250 terminals, and that runs on several operating systems, such as OS/2, PC-DOS, and Windows. Replaced by Host Access Client Package September 2000. See PC/3270.
Personal Dictation System: Speech recognition software (November 1993) for OS/2 – the flower of two decades’ continuous research funding by IBM. Claimed to have a 95%-98% accuracy rate at over 70 words per minute. Appears to be based on the RS/6000 Speech Server Series. Withdrawn November 1994.
Personal Services: Obsolete family of IBM software products on the PC, System/3x, and mainframe (including DPPX/370) providing e-mail and diary (calendar in some cases). All Personal Services products were obsoleted by, or subsumed within, OfficeVision.
Personal System/2: IBM’s PS/2 family (85xx) of personal computers announced April 1987. The name PS/2 disappeared in October 1994, in what IBM called a rationalization of its PC product branding.
Personal Typing System: A pair of hardware/software combinations that essentially turned a PS/2 model 30 with a correcting printer into a typewriter. Surely even IBM couldn’t sell it! Announced September 1989. See also 6900.
Person to Person: Person to Person/2, later renamed Person to Person for OS/2 and Windows. Multimedia groupware software for the PS/2 (announced October 1991) which enables users connected across a LAN to see exactly the same screens – WYSIWIS (What You See Is What I See), in the words of the IBM announcement. Withdrawn November 1996.
PetroConnect: IBM initiative to introduce secure, electronic commerce and information clearing houses across the Internet for the petroleum industry. Announced November 1996 and shut down soon after. See also Energy Network Exchange, Insure-commerce.
PFA: Predictive Failure Analysis. A feature of many of the eserver xSeries.
PF key: Program Function key. One of those irritating keys on the keyboard of your favorite workstation whose function varies according to the software you’re using – on System A, PF1 means Save, while on System B, PF1 means Quit. Help came in the shape of SAA’s CUA1 which banished such things forever. Then came PCs and now the confusion is between the use of the F keys in your favorite PC software and what the corresponding PF key means in a host environment. But, if you want to be truly confused, check out DEC VAXs. They have both F keys and PF keys, each with a different meaning.
PGA: A rarely used screen standard for IBM PCs.
Phoenix: IBM code name for a 128-node RS/6000.
PhoneMail: Ancient speech distribution system, originated by Rolm. When it bought Rolm, IBM liberalized PhoneMail (previously it had been available only with Rolm PABXs) and created links to PROFS and to VTMS. Despite the sale of Rolm years before, IBM did not withdraw PhoneMail until December 1997.
Physical security: Protection of equipment, real estate, hard copy records and other physical assets from theft, damage or intrusion.
PICK: Hardware-independent minicomputer operating system for commercial work. Was implemented on 9370 hardware (but not by IBM). Also available, with IBM’s blessing, on the RS/6000 (and previously on the RT PC).
Picosecond: 1/1,000,000,000,000 of a second. A time span during which even IBM would not be able to put up prices.
PID: Program IDentification.
PIM: Personal Information Management. Personal productivity software such as Sidekick or IBM’s Current. Not really a separate type of product, just another bit of marketbabble used by vendors to pretend that their product is a different kind of beast from all the other similar products on the market.
PIN: Personal Identification Number, normally numeric and usually four digits, such as the password required when using a magnetic striped card in a banking machine.
PING: Packet INternet Groper. A test of reachability in TCP/IP networks. A PING is a program used to test the ability to reach destinations by sending the destinations in question an echo request and waiting for a reply.
Pink: An Apple operating system (a follow-on to the Macintosh) which Apple was working on when it set up the Taligent joint venture with IBM. It’s probably not unreasonable to assume that the original Pink became part of TalOS.
PIP: Phased Investment Promotion. IBM sales scheme introduced late 1990 in which you pay a large chunk (typically 60%) of the price of a new box when it’s delivered, and then the rest 18 months or so later. It’s mainly being used to cushion the blow when a user is forced to make a larger upgrade than he really wants because of the big steps in some upgrade paths. Obsolete.
Pipe: Memory-sharing mechanism within OS/2. Data held within a pipe (an area of real memory) can be read as a file by many applications. Also used generically to refer to any communications channel. See also Named Pipes.
PIRP: Post-Installation Return Period.
PL/AS: IBM PL/I-like system programming language sometimes used in lieu of Assembler for IBM internal development of z/VM code and within other IBM mainframe system software products. Replacement for PL/S. The PL/AS compiler generates Assembler code, not final object code. Not available to Joe Public. Replaced by PL/X.
PL/I: Programming Language/One. Also written with an Arabic one: PL/1. Developed along with IBM's System/360, PL/I was intended to fill many of the same roles then served by COBOL, FORTRAN, and ALGOL, as well as much of the system control provided by Assembler. IBM currently offers VisualAge PL/I for z/OS, VisualAge PL/I Enterprise for OS/2 and Windows, IBM PL/I for z/OS, z/VM and VSE/ESA, IBM PL/I Set for AIX and IBM PL/I Personal for OS/2 and Windows. See also AS/400 PL/I, OS PL/I.
Plan: The basic information extracted with the bind processor from SQL statements embedded in the user’s application, and used to determine the access strategy to a relational database. The plan is stored in the database and linked with its corresponding program. Plan is also known as application plan or access plan.
Planar: IBMspeak for the main circuit board of a device – what everybody else in the electronics business calls the motherboard.
PlantWorks: Application development software to enable production engineers to create customized application programs to monitor and control production environments. Joint development by IBM and Measurex. Withdrawn June 2000.
PLC: Primary License Charge.
PLITEST: PL/I test tool that was an optional feature of the obsolete OS PL/I compiler and library. Initially replaced by INSPECT, but now replaced by the Debug Tool in the Full-Function Feature of the IBM PL/I for z/OS and z/VM compiler.
Plug-in: A program that, when installed, adds function to another program. The term was popularized by Web browsers, for which hundreds of plug-ins are available for free on the Internet, usually automatically installed after prompting the user. For example, a plug-in is required to run Windows Media from within Netscape.
Plug N Go: An all-time low in IBMspeak. Plug‘N’Go is a bundled version of the low end AS/400 introduced August 1991 in the USA, but not until January 1992 in the UK, presumably to allow Chaucer, Shakespeare, Austen, n other lovers of the English language to stop turning in their graves. By May 1993 there were 50 Plug‘N’Go solutions available, but rapidly withdrawn or renamed soon after. Not to be confused with portable PCs, which are Lug‘N’Go.
PMA: Preferred Machine Assist. A hardware (see firmware) feature that improves the performance of VSE/ESA and z/OS when running under z/VM. Enables a guest VSE/ESA or z/OS operating system to execute almost all its own privileged instructions rather than have them executed via z/VM. Superseded by PR/SM.
PMF: Print Management Facility. z/OS TSO and z/VM CMS1 interactive print utility for creating page, form, and font definitions, particularly for 3800/3900 printers. Withdrawn December 1997 for z/VM, but still available for z/OS.
PMO/2: Presentation Manager Office/2. OS/2 EE software (announced October 1991) which integrated a number of OfficeVision functions – mail, host connection, host file handling, and address book – in a WIMPS environment. Required Presentation Manager Office Support software in the z/OS or z/VM host. Support ended March 1994.
PMPS: Problem Management Productivity Services. Based on each customer’s needs, IBM would customize an OS/2 LAN-based help desk system for service call processing. Announced October 1991 and then quietly disappeared.
PNA: Programmable Network Access. IBM software, with optional toolkit, used with OS/2 to enhance communications between SNA and non-SNA systems. Makes use of the MicroChannel, and is a quite well thought-out product which IBM’s System Integration Division would customize for you. Support ended April 1993, but not withdrawn until December 1997.
PNCP: Peripheral Node Control Point. A distributed control node (similar in function to the SSCP) in an SNA Type 2.1 network. A PNCP can have a session with another PNCP without intervention from an SSCP.
PNS: Publication Notification System. A method, from IBM’s web site, to create a profile of interests, then be notified by e-mail when a publication of interest has been published or revised. Part of the IBM Publications Center.
POF: Programmed Operator Facility. Obsolete 8100/DPPX program product providing reactions to system-generated and timer-driven messages. Events (e.g., error conditions, exceptions, etc) can be handled centrally on the mainframe.
Point: Usually used in the context of Point tools, which are tools supporting just one single point within a complex process, rather than forming part of an integrated solution. Most commonly used by IBM in a derogatory way to refer to tools which support just one part of the software development life-cycle, as opposed to AD/Cycle which would have supported the whole life-cycle if it had worked.
Pointing device: IBMspeak for a mouse, light-pen, or any such thing that can be used to point at things on a screen.
Point to point: A data transmission between two locations which does not use an intermediate terminal or computer.
Policy: A set of rules, often with enforcement methods, intended to implement an organization’s decisions in a given area, such as security policy.
Polling: Generic name for a method for controlling devices (e.g., networked workstations or terminals), in which a computer calls (polls) each device in turn to see whether it wants to communicate. Contrast polling with techniques such as CSMA/CD, in which the device tells the computer when it is ready to send rather than waiting to be asked. Note that most network management software works by polling connected terminals.
POMS: Process Operations Management System. Project to build a distributed CIM1 system for OS/2 EE in which IBM participated with some customers and a company called Incode. POMS provided a way of tying together AS/400s, mainframes, and non-IBM machines for CIM applications. October 1990, IBM acquired exclusive marketing rights to POMS, and in July 1991, bought a share in Incode. IBM quit marketing POMS in October 1996, but it is still available from Incode, which changed its name to POMS, then was acquired by Honeywell in 1999, and now operates as Honeywell POMS.
Pooling: Technique for managing DASD (also known as volume or storage pooling). Pooling consists of categorizing data by factors such as performance, recovery, and application requirements, and allocating data to pools of DASD volumes according to that classification. Data types for pooling might be database, interactive temporary data, large and multi-volume datasets, and system data. Pooling is normally, and preferably, associated with a data naming convention. DFSMS formalizes this concept, refines the degree of resolution to dataset rather than volume level, and automates the process.
POP2: Principles of Operation. The name of the manual that defined the 360 and subsequently the 370 architecture. POP defines the interface to which all PCM vendors must work. Most notably, for Assembler programmers, it contains detailed descriptions of each machine instruction at their disposal. IBM has published POP manuals for some of their non-mainframe systems, as well.
Port: Generic noun and/or verb. As a noun, it means a point at which data can enter or leave a data network or individual device; as a verb it means to convert a piece of software written for one environment so that it runs in another.
Portable: General term for a computer system that can be practically carried by one person.
Portal: An entry point (implemented as a Home page) for accessing Web-based information in an organized manner, typically in a hierarchical menu-like set of hypertext links. America Online (AOL), Yahoo and the Open Directory Project (dmoz) are examples of Internet portals. Search engines are not.
POSIX: Portable Operating System Interface Standard. Operating system interface standard from the IEEE designed as a procurement reference standard for ensuring source-level application code portability. Part of the basis of the OSF and X/Open standards. Essentially a definition of what is Unix and what is not. AIX1 became POSIX-conformant as from Version 3, according to IBM, and POSIX conformance has been announced for OS/400, eserver pSeries, z/OS (Unix System Services), and z/VM (OpenExtension Shell and Utilities).
POST: Power-On Self Test.
PostScript: Language/protocol cum page description language (see PDL) developed by Adobe Systems for driving high-resolution page printers. A de facto standard which IBM uses in many of its products. IBM’s nearest home-grown equivalent is AFP/IPDS. Infoprint Server Transforms have replaced the PostScript interpreter previously available for z/OS which also output PostScript documents to AFP printers, but was clumsy and needed user intervention. See also LexRes.
POWER1: Priority Output Writers, Execution processors, and input Readers. VSE/ESA spooler released in 1968 and still going strong.
POWER3: Performance Optimization With Enhanced RISC. The IBM-invented architecture and chip introduced in the RS/6000 processor and carried forth into the eserver pSeries. Despite the exceptionally silly acronym, it’s all clever stuff with three independent functional units enabling it to perform 4-5 instructions per machine cycle.
POWERbench: AIX1 application development workstation environment available in C/C++, COBOL, and FORTRAN incarnations. The C/C++ version was withdrawn in July 1994; the others followed in January 1997. Replacement products were XL FORTRAN for AIX, C Set++ for AIX and COBOL Set for AIX.
PowerOpen: PowerOpen Association. Yet another consortium (vintage March 1993) which included IBM, Apple, Motorola, and others, and which was sworn to promote and uphold an application binary interface (ABI) based on AIX1, for machines using the PowerPC. By September 1993 there were over 50 ISVs signed up, including Microsoft. Disbanded in the late 1990s.
POWERparallel: An architecture for creating parallel processing systems built around the PowerPC family of chips. IBM promoted the architecture under the self-explanatory and poetically recherché slogan Palm tops to teraflops. First implemented in SP1, later in SP2. Obsolete.
PowerPC: A processor developed jointly by Apple, Motorola, and IBM. It has a micro-kernel based on MACH on which various operating systems – OS/2, Macintosh, and Windows – are superimposed. Apple uses it in the Macintosh, and it was used as the basis of the PowerOpen standard. The first ones were derivatives of the RS/6000 Rios chips. The first boxes built around the PowerPC were RS/6000 technical workstations and servers, announced in September 1993, with AS/400s using the thing in mid 1995. Motorola still regularly announces new version of the processor. There are even versions of the chip for embedded applications. See also PReP.
Power Platform: IBM’s pretentious name for its 25MHz 80486-based PS/2, first released June 1989 and long a forgotten piece of history, though you might still find one on eBay.
POWERquery: Set of scalable and flexible building blocks of IBM software, hardware, and consulting services for building query systems for the RS/6000 SP2 machine. Announced December 1994. Withdrawn July 1996.
POWER Visualization System: IBM’s first serious attempt at a commercial massively-parallel processor system – announced July 1991 as the 7245, for the US only, and January 1992 for the rest of the world. Uses an RS/6000 front end and up to 30 Intel 80860 processors to create a server for generating and manipulating complex images. Mainly designed to process and display supercomputer data. Withdrawn November 1995.
PP: Parallel Print.
PPCS: Parallel Processing Computer Server. IBM prototype system using up to 32 System/370 microprocessors (originally 9370s, later 9221s) all linked via an IBM channel to an IBM mainframe which keeps the whole thing going. The PPCS research was a contributor to what eventually became the Parallel Query Server.
PPDS: Personal Printer DataStream.
PPFA: Page Printer Formatting Aid. Batch printer utility for creating form and page definitions for the 3800/3900. Originally z/OS, z/VM, VSE/ESA software products and a part of PSF for AIX1. More recently, a feature of Infoprint Manager for Windows NT/2000/XP/2002.
PPP2: Point to Point Protocol. A common method of connecting a single computer to the Internet, replacing SLIP. Provides router-to-router and host-to-network connections over synchronous and asynchronous circuits.
PR/SM: Processor Resource/Systems Manager. Logical partitioning hardware technology that makes a single system, even if it has only one processor, look like multiple systems, each of which is a Logical PARtition (LPAR). For example, test and production z/OS systems, each with their own copy of the operating systems. Or Linux, VSE/ESA, z/VM and z/OS, each in their own LPAR. Only for eserver zSeries 900, starting with the 3090; iSeries 400 also supports LPARs, though not with PR/SM. Systems running under PR/SM are said to be running in Logical Partitioning Mode (LPM). Functionally PR/SM has a similar effect to VM/MHPG but with none of the z/VM overhead. Similar facilities are provided on PCM processors by Amdahl’s MDF (Multiple Domain Feature), and HDS’s LPF (Logical Partitioning Facility). The implementations are different – MDF is a time-sliced system, and PR/SM and LPF are event-driven.
PrDM: IBM SAA AD/Cycle Professional Documentation Manager/MVS & VM. Mainframe software which supports documentation creation and management. Works in conjunction with DCF and Bookmaster. Announced June 1992. Withdrawn August 1994.
Precompiler: A program which converts application-oriented statements (e.g., 4GL, CICS Command-Level, DB2) into statements of a high-level language (e.g., COBOL). The processed output is compiled in the usual manner. A COBOL program using DB2 for a CICS environment would have run the output from the DB2 precompiler through the CICS precompiler, then compiling that output with the COBOL compiler.
Precompiler Services: A z/OS DB2 API that can be called from the COBOL compiler to run the DB2 precompiler, eliminating the normal precompile job step. It also allows use of language capabilities that had been restricted by the precompiler, such as nested COBOL programs.
PRESCRIBE: A data stream used in Kyocera PRESCRIBE printers. Many IBM Infoprint printers have a feature (an optional card) that converts PRESCRIBE to PCL, allowing them to print it. Announced September 2001.
PRF: Pseudo-Random Function.
Printing Systems Manager: IBM print management software for distributed environments based on MIT’s Palladium print management reference model. Allows network administrators to manage global networks of distributed printers from a single workstation. PSM for AIX1 was announced June 1995. Replaced by InfoPrint Manager for AIX December 1998.
Private area: Area within z/OS which contains the user’s own data/programs.
PRM: Protected-Resource Manager.
Problem: In IBMspeak, there are no problems, only opportunities. Particularly intractable opportunities are challenges.
Problem Management Bridge: Problem Management Bridge/MVS. OS/2 software that runs unattended and automatically transfers problem data from Info/Man to any other problem management system. Extracts data from Info/Man running on z/OS and converts it to whatever format the other problem management system needs. Announced June 1992 and withdrawn May 1996.
Problem State: A term used in performance measurement to indicate when the machine is performing end-user work. The opposite is Supervisor State, when the machine is spending time generally managing itself.
Procedural security: Security methods relying solely on human action.
ProcessMaster: Front-end z/OS and z/VM software for IBM publishing software. Withdrawn March 1997.
Processor Availability Facility: Feature introduced on the 9021 and 9121 multiprocessors which provides transparent application recovery, by allowing an executing program to be moved from a failing processor to one which is still working. Announced April 1991.
Processor storage: The combination of central and expanded storage. Also known as real storage or, informally, as memory, to differentiate from other types of storage, like disk, tape, optical.
Prodigy: Joint networking venture between IBM and the Sears retail organization. Provides access to e-mail, news services, stockbroking (in January 1993 Prodigy claimed to be the USA’s largest on-line stockbroker), weather forecasts, consumer databases, etc from PCs. By the beginning of 1996, Prodigy had slumped to number three in the proprietary network market, and was sold for around $750M less than IBM and Sears had spent on it.
ProductManager: IBM CIM1 software, announced October 1989 for the z/OS TSO environment. Manages product and process information from the first glimmering in the inventor’s mind all the way to manufacturing. Member of the CIM Advantage family. Over the years AIX and non-IBM platform versions were announced, and in June 1996, the z/OS version was withdrawn. Since then ProductManager has been renamed ENOVIAPM (ENOVIA ProductManager) and currently runs on AIX1, HP-UX, Sun Solaris and SGI OS.
Professional Work Manager: Obscure PC/mainframe system mainly directed at program developers. Withdrawn October 1990.
PROFS: PRofessional OFfice System. z/VM office system aimed at the professional, technical, managerial user. Provided text management, diary, messaging, etc. Most parts of PROFS were highly regarded by users. The end of PROFS was presaged by the announcement of OfficeVision/VM, and it was finally withdrawn from marketing in June 1991.
Program: Computer program.
Program Management Binder: z/OS DFSMS component that replaced the Linkage Editor, as a way to make compiled object code into an executable program. Includes an API so that it can be called by programs wanting its services. See also Program Management Loader.
PROLOG: PROgramming in LOGic. Language mainly used for developing artificial intelligence and expert systems. Available from IBM on z/OS, z/VM, OS/2 and, in Europe, AIX, but by February 1996 it had all been withdrawn. There are, however, many non-IBM compilers available as both supported products and freeware, especially in the Unix environment.
Proof of Entitlement: An IBM-issued legal document given to a customer for a specific piece of software. It provides evidence of your authorization to use this Program and of your eligibility for warranty services, future upgrade program prices (if announced), and potential special or promotional opportunities.
Proprietary: Proprietary is used to refer to architectures and standards owned by a hardware or software vendor (usually IBM). The word’s usually used in opposition to open, with quasi-moralistic overtones – proprietary is bad, open is good. The theory goes that proprietary systems (z/OS, SNA, SAA, etc) lock the user in, and remove freedom and choice. This is, of course, utter codswallop; z/OS or SNA users have as much, if not more, choice of hardware and software than users of allegedly open Unix boxes. An z/OS user who gets fed up with IBM has far less trouble moving his work to an Amdahl box than an HP Unix user would have moving to another vendor’s Unix implementation.
Protected mode: A mode of Intel processors, beginning with the 286, which provides hardware memory protection. Important for multitasking systems, and, historically, for breaching the 640KB barrier in PC-DOS.
Proteon: Router vendor which set up a cooperative deal with IBM early 1994 to develop low-end routers.
Protocol: A set of standards for the format and control of data being communicated within a system. Typically across a network, the definition of the communications between two pieces of hardware or software: format of each transmission, allowable responses and perhaps even timing.
Protocol boundary: SNAspeak for the point in a network at which a message protocol changes as it passes from one network layer to the next. The boundary protocol insulates one area of a network from another, so that neither needs to know the details of the physical devices in the other. The NCP in an IBM FEP acts as a hardware protocol boundary, and APIs, such as the LU6.2 API, define the software protocol boundary. See also Bridge, Gateway.
Protocol converter: A device for converting data from one protocol (communications standard) to another. At one time protocol converters were widely used in the IBM world to make very cheap async terminals appear to IBM kit as more expensive 3270- or 5250-type terminals.
Proxy server: A server that receives and fulfils requests intended for another server.
PRPQ1: Programming Request for Price Quotation. IBM terminology for a customer request for a price quotation on alterations or additions to the functional capabilities of system control programming or licensed programs.
PRPQ2: Product Request Price Quotation. Product from IBM which is not on the price list – you have to go cap in hand to your IBM sales office to ask them to quote you a price. The PRPQ is a mechanism for controlling the spread of products which IBM is unenthusiastic about selling or supporting.
PS/1: Low-end PC family launched June 1990, initially as a home model. With the hiving off of PCs into the IBM PC Company in September 1992, PS/1 became the name of IBM’s cheaper PC models for home or business. In October 1994 the name disappeared altogether to be replaced by Aptiva. See also ValuePoint, Ambra.
PS/3701: See Personal Services/370.
PSAF: Print Services Access Facility. z/OS and z/VM software that provides menu-driven selection of formatting and printing options to print line-mode data and page-mode data on the 3800 and subsequent families of page printers. The z/VM version was withdrawn December 1997.
pSeries: The eserver pSeries replaced the RS/6000 October 3, 2000. It is IBM’s AIX1 platform covering the range from simple workstations to host systems, including 64-bit hardware for processor-intensive applications in areas such as engineering. NUMA-Q, acquired from the merger with Stratus, has also been absorbed into the pSeries line.
Pseudo-conversational: The term is typically used in CICS, to describe the strongly recommended approach: a type of transaction program which simulates a continuous dialog, but which in reality releases its resources at the end of each terminal interaction.
PSF: Print Services Facility. On the mainframe, z/OS, z/VM and VSE/ESA versions provide the printing system that communicates between the spool subsystem and printers to provide access to AFP formatting and output capabilities. PSF/400 provides similar capabilities in the OS/400 environment. Versions for AIX1 and OS/2 have been replaced by Infoprint Manager, although OS/2 users would have to convert to Windows to use it.
PSnS: Personally Safe‘n’Sound. PC utility that stores files on a variety of backup devices either stand-alone or on a network. Withdrawn December 1997.
PSS1: Packet SwitchStream (aka Packet Switched Service). Formerly, a UK public data network run by British Telecom (BT).
PSS2: Programmable Store System.
PSSP: Parallel System Support Programs for AIX1. Software for installation, operation, management and administration of the pSeries, attached servers and PSSP cluster configurations from a single point of control.
PSTN: Public Switched Telephone Network.
PSW: Program Status Word. A hardware register (double word) in the mainframe much loved by systems programmers. The PSW contains the address of the next instruction to be executed and, when an application or system software error occurs, why it happened and other status information.
PTF: Program Temporary Fix. An official IBM temporary patch to a program. Most are less temporary than IBM and its users would wish. PTFs are distributed on PUTs. Sometimes the term APAR is used instead of PTF. See also PUT2.
PTM: Packet Transfer Mode. Mechanism for high-speed communications based on variable-length packets (as demonstrated by Frame Relay) rather than fixed-length cells (the ATM2 method). Each approach raises its own performance and compatibility issues. IBM’s high-speed networking strategy involves a mixture of ATM and PTM: the idea is that Frame Relay will be used extensively within IBM networks, and ATM interfaces will be provided to the outside world. See also TNN.
PTOCA: Presentation Text Object Content Architecture. Architecture defining the presentation characteristics of text data, including location of characters, line direction, formatting etc. PTOCA is a superset of the text format standards of IPDS.
PtP: Peer to Peer.
PTT: Poste, Télégraphe, et Téléphone. Generic name for national bodies responsible for telecommunications within a country, e.g., British Telecom, Deutsche Bundespost, Nippon Telephone, and Telegraph Public Corporation.
ptx: Operating System for Intel-based NUMA systems, including models of the IBM eserver xSeries that replaced the NUMA-Q acquired from the merger with Stratus. Can run Linux, ptx, z/OS, z/VM and VSE/ESA applications simultaneously.
PU1: Physical Unit type within SNA (also known as Node Type or NT). The software in an SNA node controlling the node’s communications hardware. In general, the higher the number of the PU, the greater the intelligence in the PU. For practical purposes, PU1s are dumb controllers or terminals, PU2s are intelligent cluster controllers or terminals, PU4s are communications controllers, and PU5s are mainframes. Synonymous with node type within SNA. The type 2.1 node allows local user ports to communicate without going through a host node’s SSCP services. The type 2.1 node + LU6.2 bought democracy to autocratic, host-dominated SNA.
PU2: Processor Unit.
Publication Ordering System: IBM’s customer-accessible application for buying manuals and other documentation.
PU Concentrator: Type of SNA-LAN Gateway that aggregates the LUs in multiple SNA nodes (e.g., PCs) into a single virtual node, with up to 254 LUs, so that a mainframe does not have to support as many DSPUs. PU Concentrator capability is available with OS/2, NetWare for SAA, etc.
PU Passthrough: Technique for allowing a TRN terminal to talk across an SNA network to a host VTAM despite the incompatibility of the SNA and TRN protocols. Basically it’s a protocol converter. Implemented in IBM FEPs, cluster controllers (3174), and integrated communications adapters (ICA) on small mainframes.
Purple wire: IBMspeak for wire installed by IBM field engineers to circumvent problems discovered during testing or debugging. These purple wires are, however, often yellow. See also blue wire, red wire, yellow wire.
PWM: Professional Work Manager. Embryonic CASE1 environment which used EZ-VU and HLLAPI to provide an infrastructure for the creation of a programmer’s workbench on a PC or PS/2. WASE was a tailored version of PWM. Withdrawn October 1990.
PWSCF: VM Personal Workstation Communication Facility. PRPQ2 software announced in 1990 which uses APPC to enable PWSs to talk to z/VM CMS1, and thus provides transparent access to host z/VM resources from workstations.