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A glossary of terms important to IBM mainframe machines

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UACC:  Universal Access Authority. The RACF default access authority to a resource when a user or group has not been given explicit access authority to that resource. UACC is overridden by the OPERATIONS and RESTRICTED user attributes. See also OPERATIONS attribute, RESTRICTED attribute.

UADS:  User Attribute DataSet. TSO/E’s access control file: a PDS1 with a member for each user.

UCS:  Universal Character Set.

UDB:  Universal DataBase. See DB2 Universal Database.

UDDI:  Universal Description, Discovery and Integration. An emerging standard originally from IBM, Microsoft, and e-business heavyweight Ariba to create a shared business registry on the Web to expedite and streamline B2B e-business processes. Supported by WebSphere Application Server. See also WS-Inspection.

UDF1:  User Defined Function. DB2 feature that allows new SQL functions to be defined.

UDF2:  Universal Disk Format. A file system format used on DVD and CD, including packet writing on CD-R and CD-RW.

UDFS:  User Defined File System. OS/400 file system similar to the Windows hierarchical file system. Created and managed by users.

UDP:  User Datagram Protocol. An Internet protocol that provides unreliable, connectionless datagram service. Its only advantage over TCP is lower overhead.

UDT:  User Defined Data Type. DB2 feature that allows new DB2 data types to be defined, based on existing ones.

UFC:  Universal Feature Card. UFCs let customers tailor certain IBM switches and other network hardware by changing the UFC only, not the entire switch.

UGC:  Utility Graphics Consultants – a Colorado-based company specializing in GIS. IBM bought a stake in UGC in November 1990.

UI:  User Interface.

UIA:  User Interface Architecture. IBM term for a set of standards aimed at providing a consistent syntactic and semantic environment for user interaction – screens, keyboards etc. Effectively superseded by SAA’s CUA1, which was much the same thing.

UID:  z/OS Unix System Services user identification.

UII:  Unix International Inc. Group of vendors set up in 1988 to promote Unix. Supported by AT&T in opposition to the OSF. Acted as a user group made up entirely of vendors. It became somewhat redundant when X/Open won the Unix standard, and by the end of 1993 it had lost all enthusiasm for life and committed corporate hara-kiri. See also NewOrg.

UIT:  Union Internationale des Télécommunications. Formerly a UN agency concerned with telecommunications, of which the CCITT was a part. Reorganized and renamed ITU.

UltiMail:  IBM e-mail client products for OS/2 announced mid 1994. Work with the AnyMail e-mail servers. Replaced by IBM WorkGroup May 1995.

Ultimedia:  This, according to IBM’s October 1991 press release, is the new brand that will identify all of IBM’s multimedia products and services... and express IBM’s dedication to deliver uncompromising multimedia technology, customer solutions, and creator support. It’s a mixture of software and hardware gizmos, including PCs, OS/2 software, etc. Very little of it remains today.

UltraStar:  Family of high-performance, high-capacity (2GB and 4GB in first models) 95mm disk HDAs available from 1995 on. Highly reliable – IBM claims 1,000,000 hours MTBF. Used in the 7133 and RAMAC2 2 and 3, and sold into the OEM market. See also TravelStar.

Ultrix:  DEC’s version of Unix. Renamed Tru64 UNIX.

UML:  Unified Modeling Language, the industry standard notation for object-oriented analysis and design. An OMG specification.

Unbundling:  The practice of selling hardware and/or software in separate packages, so that users only pay for what they want. IBM unbundled its software and hardware as a result of anti-trust pressure in the US (see Consent decree). But seems to be reversing the trend in recent years.

Uncataloged:  z/OS datasets that are not listed in the Master catalog or any of the user catalogs listed in the Master catalog. But is listed in a VTOC. Since there is a VTOC for each disk volume, there can be multiple uncataloged datasets with the same name, which is why the VOLSER of the volume must be specified. Uncataloged datasets cannot exist on SMS1-managed disk volumes.

Unformatted System Services:  SNA terminology for a system services control point facility that translates a character-coded request, such as a logon or logoff request, into a field-formatted request for processing by formatted system services; and that translates field-formatted replies and responses into character-coded requests for processing by a logical unit (LU).

UNI:  User-to-Network Interface. The interface between an ATM2 user and the ATM network.

Unicode:  A character set coding scheme, just as ASCII and EBCDIC are, but with the ability to represent all written human languages. The character code is 16 bits wide which yields up to 65,536 characters (compared to EBCDIC’s 256). The Unicode committee was set up in 1989, and included IBM, Apple, and Microsoft among its number.

Uninterruptible power supply:  A buffer between utility power, or other power source, and a system that requires a consistent power source that is both uninterrupted, of a predefined quality, and without surges.

Uniplex:  Integrated office computing suite for Unix. Developed by the UK Uniplex company, and sold by IBM as an AIX1 product. Withdrawn by IBM December 1994, but still available through Uniplex.

Unit of work:  The statements executed between one commit point and the next – usually a group of SQL statements which would need to be rolled back as a group if any single statement in the group could not be executed. It’s the basic recovery unit. See also Remote Unit Of Work.

Unitree:  AIX storage management product – a sort of AIX1 equivalent of DFSMShsm. Manages a storage hierarchy, and provides automatic file migration. Announced October 1992. Withdrawn August 1995.

Universal Access Authority:  See UACC.

Universal Connection:  Reports inventories of software and hardware on your machine to IBM to help them personalize electronic support based on your system data. Announced in 2000 for OS/400.

Universal Disk Format:  See UDF2.

Unix:  A misspelling of UNICS (UNiplexed Information and Computing Service). A hardware-independent operating system originally for minicomputers and now PCs, too. Once described as a catch-all term for many operating systems that share some features and a common parentage. Unix was developed by AT&T and owned by USL, which passed from AT&T to Novell at the end of 1992. Widely promulgated as a standard operating system, but still has not been as widely accepted as Unix buffs keep expecting it to. After all, it was designed to provide a program development environment. Unix keeps coming in waves: to replace mainframes, as a Web server and to replace Windows on the workstation. Each wave begins with a concept, its shortcomings revealed as it is implemented, and competitive technologies having time to catch up as the shortcomings are addressed. IBM had at various times offered eight different versions of Unix, but showed little real enthusiasm for the subject, until September 1991 when it suddenly became an ingredient in the flavor of the year – openness. And IBM AIX1 was born. The IBM-supported OSF has developed an independent version of Unix. October 1993, control of Unix fell into the hands of X/Open who trademarked only the capitalized version UNIX. Currently it is Linux that is receiving the vast majority of Unix attention, both in the marketplace and by IBM. See also POSIX.

Unix International Inc:  See UII.

Unix System Services:  A full function Unix implementation under z/OS that complies with the POSIX standard. Implemented as an operating environment that you switch to within z/OS, much as you started up Windows 3.x in PC-DOS. Originally introduced as OpenEdition.

UnixWare:  A version of the Unix operating system. Caldera bought Santa Cruz Operation (SCO) who acquired UnixWare from Novell who renamed the original Unix they acquired from AT&T.

UNMA:  Unified Network Management Architecture. AT&T’s blueprint for end-to-end control of voice/data networks at the physical level. On the surface UNMA looks like it’s competitive with IBM’s NetView, but the reality is that UNMA controls the physical network on which the SNA network resides, whereas NetView controls the SNA network itself.

UP:  Uniprocessor.

UPC:  Universal/Uniform Product Code. The bar code technology behind those appalling little stripes that are used to conceal the price of things until you get to the check-out when you discover that the thing you’ve chosen costs far more than it’s worth, at which point you’re too embarrassed and pressured to put the item back on the shelves so you end up buying things which you never would have bought if they’d been properly labeled on the shelf in the first place. A massive retrograde step for the consumer, but a great leap forward for retailers and vendors of UPC technology. IBM supports UPC in its POS1 systems, and – would you believe – even has an architecture for the whole ghastly farrago (see BCOCA).

Upgrade:  A change to a new version/release of a product. In IBM terms, a CPU upgrade (as opposed to a new machine) is a change to a configuration that preserves the serial number of the original machine. For a processor change to be an upgrade rather than a new CPU, some portion of the value of the old machine has to be retained. This principal first became enshrined in the ES/9000 range, where the machine was designed with a basic range of infrastructure support – power supplies, cooling, etc – which are preserved between upgrades of memory, processors etc. See also Fork lift upgrade.

Upload:  To transfer files from a workstation to a host. For example, graphics or media files for a Web page from workstation to Web server. cf. Download.

Upper CASE:  See CASE1.

UPS:  See Uninterruptible Power Supply.

URL:  Uniform Resource Locator. The addressing method used for Web pages. Typically takes the form

Usage pricing:  The principle of charging for software on the basis of the amount of work done – e.g., the number of transactions, amount of batch data processed, etc. Also known as Measured Usage Pricing. The intention is to establish a closer price to value relationship. Several ISVs do this, and April 1994, IBM introduced it. See also Customer value pricing, Model group, MSU, SU, User-based pricing.

USB:  Universal Serial Bus. Hot-pluggable ports that first appeared on laptops, then desktop PCs, that allow easy connection and disconnection without a screwdriver or having to open the machine case.

User ASP:  Grouping some iSeries 400 disk drives together and assigning the group an Auxiliary Storage Pool (ASP).

User attribute:  Special RACF privileges assigned to a user.

User Attribute DataSet:  See UADS.

User-based pricing:  The principle of charging for software based on the number of users (e.g., connected workstations). Available on a number of office systems products. See also Model group, Usage pricing. Also known as PUP (per user pricing).

User catalog:  In z/OS, an ICF catalog created to reduce the number of entries in the Master Catalog, thereby improving performance. See also ICF2.

User certificate:  A digital certificate associated with a RACF user ID that authenticates the user’s identity.

User dataset:  Any dataset1 named with a RACF user ID as a high level qualifier, though an installation can choose another qualifier level.

User Defined File System:  See UDFS.

User ID:  RACF’s identification for a person using computer resources, usually no more than seven characters in length (a TSO restriction), beginning with a letter or #, $ or @.

User ID association:  A relationship between two user IDs defined by the RACLINK command.

User identification:  See user ID.

User identification and verification:  Securely associating a user with a process, e.g., identification during logon or batch job initiation by looking up the user ID; verification by checking the password.

User name:  The 1-20 character name that RACF stores for each user ID, typically including the surname of the user.

User profile:  Where RACF stores information specific to a single user ID.

User Profile Management:  No, it’s not a threat of physical assault to people who don’t buy IBM products. As a generic term, refers to the use of software to change attributes associated with user IDs, as well as add and delete user IDs. Also a feature of OS/2 which permits access to OS/2 and LAN functions through a single user ID and password.

USI:  Unix Software International. Prior to its sale to Novell, the AT&T subsidiary that owned Unix System V.

USL:  Unix Systems Laboratories. The company set up by AT&T to look after Unix. About 22% of USL was sold to other vendors (not including IBM) in May 1991, and by mid 1993 AT&T had relinquished control by selling 75% of USL to Novell.

US Memories:  Company conceived mid 1989 by a number of vendors, including IBM, DEC, Intel, and HP, to manufacture dynamic memories (DRAM) using IBM technology. The company was an attempt to make sure that the Japanese wouldn’t be able to corner the market in DRAMs again in the way they did in the mid 1980s, when they were perceived as causing a great deal of damage to the US computer industry. Unfortunately the company was stillborn in January 1990.

USS1:  See Unix System Services.

USS2:  See Unformatted System Services.

UTOKEN:  The RACF user security token.

UTP:  Unshielded Twisted Pair. Type of cable very similar to that used by standard internal telephone systems. Recommended by IBM for 4Mbps TRN and, with a few caveats, for 16Mbps. More recently, used for 100Mbps Fast Ethernet and FDDI. UTP is about one tenth to one fifth the cost of fiber, and one quarter the cost of shielded twisted pair (STP).

UVM:  Universal Virtual Machine. Proposed IBM product which will allow developers to use languages other than Java to build platform independent applications. First announced June 1997 but not mentioned since in anything but IBM trademark lists.