IBM Terminology

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z #

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 X12

A protocol from the American National Standards Institute (ANSI) for electronic data interchange (EDI).

 X.121

A CCITT Recommendation that provides a method for the international numbering of X.25 packet-switching data networks.

 X.21

(1) See Recommendation X.21.

(2) See specification X.21.

 X.21bis

In data communications, an interim specification of the CCITT that defines the connection of data terminal equipment (DTE) to an X.21 (public data) network using V-series interchange circuits such as those defined by CCITT V.24 and CCITT V.35.

 X.25

A CCITT standard that defines an interface to packet switched communications services.

 X.25 NCP Packet Switching Interface (NPSI)

An IBM licensed program that allows SNA users to communicate over packet switching data networks that have interfaces complying with CCITT Recommendation X.25. It allows SNA programs to communicate with SNA or non-SNA equipment over such networks.

 X.25 protocol

The connection-mode network service that the CCITT specifies in Recommendation X.25.

 X.25 protocol ID

In OSI, a technique that OSI Communications Subsystem uses to pass an NSAP address when using the 1980 level of the X.25 protocol.

 X.25 subnetwork

In OSI, a subnetwork that conforms to the X.25 protocols.

 X.400

A CCITT Recommendation for international electronic mail (messages).

 X.500

The directory services standard of ITU, ISO, and IEC.

 X.509 certificate

A certificate that contains information that is defined by the X.509 standard.

 X.75

In data communications, a specification that defines ways of connecting two X.25 networks.

 XA

A bidirectional interface between one or more resource managers that provide access to shared resources and a transaction manager that monitors and resolves transactions. See also distributed transaction, XA transaction.

 Xalan processor

An XSLT processor that is part of the Apache project. See also XSL Transformation.

 XA transaction

(1) A global transaction that adheres to the X/Open standard for distributed transaction processing (DTP).

(2) In an XA-enabled environment, a unit of work involving one or more resource managers that is coordinated by a transaction manager. See also XA.

 X-axis

In printing, the axis perpendicular to the direction in which the paper moves through the printer. See also Y-axis.

 XBSA

An industry-standard API set for backup and restore utilities.

 XCF

See cross-system coupling facility.

 XCF couple data set

data set that is created through the cross-system coupling facility (XCF) couple data set (CDS) format utility and, depending on its designated type, is shared by some or all of the systems in a sysplex.

 XCF group

The set of related members defined to SCF by a multisystem application in which members of the group can communicate with (send data to and receive data from) other members of the same group. All MERVA systems working together in a sysplex must pertain to the same XCF group.

 XCF-local mode

The state of a system "..in which the cross-system coupling facility (XCF) provides limited services on one system and does not provide signaling services between MVS systems.

 XCF member

A specific function of a multisystem application that is defined to XCF and assigned to a group by the multisystem application. A member resides on one system in a sysplex and can use XCF services to communicate with other members of the same group.

 XCF PR/SM policy

In a multisystem sysplex on PR/SM, the actions that the cross-system coupling facility (XCF) takes when one MVS system in the sysplex fails. This policy provides high availability for multisystem applications in the sysplex.

 X Client

An application program that uses the X protocol to communicate windowing and graphics requests to an X Server.

 XDM

See XQuery and XPath data model.

 XDM instance

Data conforming to the XQuery and XPath data model (XDM). See also XML data, XQuery and XPath data model.

 XDO

See extended data object.

 XDoclet

An open, source code generation engine that uses special JavaDoc tags to parse Java source files and generate output such as XML descriptors or source code, based on templates.

 XDR

See External Data Representation.

 XDS

(1) See X/Open Directory Services.

(2) See XML data specifier.

 XES

See cross-system extended services.

 X-extent

A measurement along the X-axis.

 X extent

A separate extent, part of the system log. During backout in emergency restart, system log records are written to the X extent. The presence of an X extent is mandatory if CICS Transaction Server is using a local DL/I system; otherwise, it is optional. The X extent can be used for audit purposes.

 X field

The primary data field in a chart. In a line chart, typically the X field appears along the horizontal axis. For example, an X field can represent cost data for the elements that appear along the horizontal axis of the chart.

 XHTML

See Extensible Hypertext Markup Language.

 XID

(1) See transaction identifier.

(2) See exchange station ID.

(3) See exchange identification.

(4) See X/Open identifier.

 XLT

See transaction list table.

 XMI

See XML Metadata Interchange.

 XML

See Extensible Markup Language.

 XML attribute

A name-value pair within a tagged XML element that modifies certain features of the element.

 XML catalog

A catalog that contains rules specifying how an XML processor should resolve references to entities. Use of a catalog eliminates the need to change URIs within XML documents as resources are moved during development.

 XML collection

A collection of relational tables from which XML documents can be composed or into which XML documents can be decomposed.

 XML column

(1) In XML Extender, a column of a table that has a user-defined data type of XMLVARCHAR, XMLCLOB, or XMLFILE.

(2) A column of a table that stores XML values and is defined using the SQL built-in data type XML.

 XML data

(1) Data of type XML, including serialized XML or XDM instances. See also serialized XML, XDM instance.

(2) A collection of hierarchical nodes, based on XML instance documents, that can be stored in an XML column or can be returned from an XML column by an SQL or XQuery statement.

 XML data specifier (XDS)

A string specifying the name, location, and validation schema for a file containing stored XML data. The import, export, and load utilities use an XDS to identify XML-formatted content that must be stored separately from the main data file.

 XML data type

A data type for XML values.

 XML data type column

A column of a table that stores XML values and is defined using the data type XML.

 XML digital signature

A specification that defines the XML syntax and the processing rules to sign and verify the digital signatures for the digital content.

 XML document

A well-formed XML artifact that conforms to the XML specification and contains markup tags along with the content, with exactly one root element.

 XML document definition

A reference to either an XML DTD document definition or an XML schema document definition.

 XML domain

The message domain that includes all messages that conform to the W3C XML standard. The XMLNS domain is an extension of the XML domain and contains messages that conform to the same standard and that can exploit the namespaces feature of the XML specification. Messages in this domain are processed by the XML parser. See also BLOB domain, IDoc domain, JMS domain, MRM domain.

 XML element

A logical structure in XML that is delimited by a start tag and an end tag.

 XML encoding declaration

The attribute of an XML or TEXT declaration named encoding and its value, which specifies the name of the encoding scheme of XML data.

 XML encryption

A specification that defines how to encrypt the content of an XML element.

 XML index

See index over XML data.

 XML lock

A column-level lock for XML data. The operation of XML locks is similar to the operation of LOB locks.

 XML mapping template

This template processes inbound XML messages and translate them to WebSphere Commerce command parameters. The mapping template file defines how to map the elements of an incoming XML message into the target command parameters.

 XML message mapper

A mechanism that converts the incoming XML message into a Java object that the target command expects. A message mapper can be registered with the instance_name.xml configuration file and is uniquely by a message mapper ID. The XML message mapper uses the mappings defined in the mapping template file to convert the XML message into the corresponding Java command parameter.

 XML Metadata Interchange (XMI)

A model-driven XML integration framework for defining, interchanging, manipulating, and integrating XML data and objects. XMI-based standards are in use for integrating tools, repositories, applications and data warehouses.

 XML namespace

A collection of names, identified by an Universal Resource Identifier (URI) reference, used in XML documents as element types and attribute names. An XML namespace allows a user to include multiple XML vocabularies in a single XML document without ambiguity of names.

 XML node

The smallest unit of valid, complete structure in a document. For example, a node can represent an element, an attribute, or a text string.

 XML node ID index

An implicitly created index, on an XML table that provides efficient access to XML documents and navigation among multiple XML data rows in the same document.

 XML parser

A program that reads XML documents and provides an application with access to their content and structure.

 XML parsing

The process of converting a character string or binary string into an XML value. This is the inverse of serializing.

 XML Path Language (XPath)

A language that is designed to uniquely identify or address parts of source XML data, for use with XML-related technologies, such as XSLT, XQuery, and XML parsers. XPath is a World Wide Web Consortium standard.

 XML pattern

A slash-separated list of element names that describes a path through an XML document and through specific node characteristics. The pattern selects elements that match the specifications. XML patterns are specified to create indexes on XML columns in a database.

 XML publication

In event publishing, an object that identifies what changes are published from a source table to a user application. The Q Capture program publishes changes from a source table and puts those changes on a send queue in XML format. See also Q subscription, replication source.

 XML publishing function

A function that returns XML values from SQL values.

 XML schema

(1) A mechanism for describing and constraining the content of XML files by indicating which elements are allowed and in which combinations. XML schemas are an alternative to document type definitions (DTDs) and can be used to extend functionality in the areas of data typing, inheritance, and presentation.

(2) A means for defining the structure, content, and semantics of XML documents as defined by a World Wide Web Consortium (W3C) recommendation.

 XML Schema Definition (XSD)

An instance of an XML schema written in XML Schema definition language. An XML Schema Definition ifile has the extension .xsd. The prefix "xsd" is also typically used in the XML elements of the XSD file to indicate the XML Schema namespace.

 XML Schema Definition Language (XSD, XSDL)

A language for describing XML files that contain XML schema.

 XML schema document

An XML document with <schema> as the root element that defines the components in one namespace of an XML schema. An XML schema with components in more than one namespace consists of multiple XML schema documents.

 XML Schema Infoset Model (XSD)

A library that provides an API for manipulating the components of an XML Schema, as described by the W3C XML Schema specifications.

 XML schema repository (XSR)

A repository that allows the DB2 database system to manage dependencies on externally referenced XML artifacts in XML instance documents within a database. Supported XSR objects include XML schemas, document type definitions (DTDs), and other external entities. When registered with the XSR, these objects have a unique identifier and can be used to validate XML instance documents. See also XSR object.

 XML serialization function

A function that returns a serialized XML string from an XML value.

 XML shredder

A function that parses an XML document, extracting rows of data from an XML table.

 XML statistics

The statistics that are collected on XML data that is stored in an XML column. The information includes path distribution statistics, which show the frequency of all distinct root-to-node paths. The information also contains path-value distribution statistics, which show the frequency of XML value strings that are truncated to fixed-length prefixes to conserve space.

 XML subtype indicator

An indicator that specifies that a base LOB data type is used to hold XML data.

 XML table

An auxiliary table that is implicitly created when an XML column is added to a base table. This table stores the XML data, and the column in the base table points to it.

 XML table space

A table space that is implicitly created when an XML column is added to a base table. The table space stores the XML table. If the base table is partitioned, one partitioned table space exists for each XML column of data.

 XML token

A security token that is in an XML format, such as a Security Assertion Markup Language (SAML) token.

 XML value

See XDM instance.

 XML Wire Format

The physical representation of a message in the MRM domain that can be parsed as XML.

 Xname resource classes

The general resource classes that CICS uses based on X name system initialization parameters. For example, if XTRAN=YES is specified, TCICSTRN and GCICSTRN are used.

 XOM

See X/Open Object Management.

 X/Open

An industrial consortium that produces specifications and test suites to resolve incompatibilities among different computer systems and software components.

 X/Open Directory Services (XDS)

An application program interface (API) that Distributed Computing Environment (DCE) uses to access its directory service components.

 X/Open identifier (XID)

A work ID that is a possible identifier for a distributed transaction used in the X/Open model.

 X/Open Object Management (XOM)

An interface for creating, deleting, and accessing objects. Because XOM is object-oriented, each object belongs to a particular class, and classes can be derived from other classes, inheriting the characteristics of the original class. The representation of the object is transparent to the programmer; the object can be manipulated only through the XOM interface.

 X/Open XA

The X/Open Distributed Transaction Processing XA interface. A proposed standard for distributed transaction communication. The standard specifies a bidirectional interface between resource managers that provide access to shared resources within transactions, and between a transaction service that monitors and resolves transactions.

 XP

See extreme programming.

 XPACK

A digital trunk processor implemented using DSP technology on the DTXA without the need for external hardware. One XPACK is directly equivalent to one SPACK. One DTXA provides up to four XPACKs on a PCI card. See also VPACK, SPACK.

 XPath

See XML Path Language.

 XPath expression

An expression that searches through an XML document and extracts information from the nodes (any part of the document, such as an element or attribute) in that document.

 XPI

(1) See exit programming interface.

(2) See user exit programming interface.

 XPLINK

See Extra Performance Linkage.

 Xp,Yp coordinate system

The logical-page coordinate system that describes the size, position, and orientation of a logical page.

 XQuery and XPath data model (XDM)

The abstract logical structure that defines all permissible values in the XSLT 2.0, XQuery 1.0, and XPath 2.0 languages. The XDM is described in terms of sequences of atomic values and nodes. See also sequence, atomic value, node, XDM instance.

 XQuery constructor

See constructor.

 XQuery expression

An expression that operates on instances of the XQuery and XPath data model (XDM) and returns instances of the data model.

 XQuery language

An XML query language for interpreting, retrieving, and modifying data as defined by the XQuery and XPath data model, such as XML documents. XQuery Version 1.0 is an extension of XPath Version 2.0.

 XRC

See extended remote copy.

 XRF

See extended recovery facility.

 XRF-capable IMS subsystem

An IMS subsystem defined so that it can work with an alternate subsystem.

 XRF-capable terminal

In CICS Transaction Server, a remote SNA VTAM terminal connected through a boundary network node IBM 3745/3725/3720 Communication Controller with an NCP that supports XRF. In an XRF configuration, this is a class 1 terminal and has a backup session to the alternate CICS system.

 XRF complex

The CPCs and the licensed programs in the active and the alternate that provide XRF for IMS users.

 XRF takeover

See takeover.

 XRST

See extended restart.

 XSD

(1) See XML Schema Definition Language.

(2) See XML Schema Definition.

(3) See XML Schema Infoset Model.

 XSDL

See XML Schema Definition Language.

 xSeries

The product name of an IBM eServer product that emphasizes industry-standard server scalability and self-managing server technologies. It is the successor to the Netfinity family of servers.

 X Server

A program that interprets the X protocol and controls one or more screens, a pointing device, a keyboard, and various resources associated with the X Window System, such as graphics contexts, pixmaps, and color tables.

 XSL

See Extensible Stylesheet Language.

 XSL style sheet

Code that describes how an XML document should be rendered (displayed or printed).

 XSLT

(1) See XSL Transformation.

(2) See Extensible Stylesheet Language Transformation.

 XSLT function

Function that is defined by the XSL Transform (XSLT) specification for the manipulation of numbers, strings, Boolean values, and node-sets.

 XSL Transformation (XSLT)

A standard that uses XSL style sheets to transform XML documents into other XML documents, fragments, or HTML documents. See also Xalan processor.

 XSM

See cross-site mirroring.

 XSR

See XML schema repository.

 XSR object

An XML artifact that is registered in the XML schema repository (XSR) and is used to validate XML instance documents. Supported XSR objects include XML schemas, document type definitions (DTDs), and other externally referenced entities. See also XML schema repository.

 Xt intrinsics

In the Enhanced X-Windows Toolkit, a set of management mechanisms that provides for constructing and interfacing between composite widgets, their children, and other clients. Also, intrinsics provide the ability to organize a collection of widgets into an application.

 X Window System

A software system, developed by the Massachusetts Institute of Technology, that enables the user of a display to concurrently use multiple application programs through different windows of the display. The application programs can execute on different computers.

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 Y-axis

In printing, an axis parallel with the direction in which the paper moves through the printer. See also X-axis.

 yellow alarm

See remote alarm indication.

 Y-extent

A measurement along the Y-axis.

 Y field

A secondary data field in a chart. In a line chart, typically the Y fields appear along the vertical axis. For example, an Y field can represent resources whose costs are represented along the vertical axis of the chart.

 yielding loop

A loop characterized by returning control at some point to a CICS routine that can suspend the looping task. However, the looping task will eventually be resumed and so the loop will continue.

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 z/Architecture

An IBM architecture for mainframe computers and peripherals. The zSeries family of servers uses the z/Architecture. It is the successor to the S/390 and 9672 family of servers. See also Enterprise Systems Architecture/390.

 ZCS

See zero code suppression.

 zero code suppression (ZCS)

A coding method used with alternate mark inversion to prevent sending eight successive zeros. If eight successive zeros occur, the second-least significant bit (bit 7, with the bits labeled 1 through 8 from the most significant to the least significant) is changed from a 0 to a 1. AMI with ZCS does not support clear channel operation.

 zero suppression

The substitution of blanks for leading zeros in a number. For example, 00057 becomes 57 with zero suppression.

 zFS

See z/OS file system.

 zone

A collection of fibre-channel device ports that are permitted to communicate with each other using the fabric. Types of device ports for zone purposes are node ports (N_ports) or node loop ports (NL_ports). Any two N_ports or NL_ports that are not members of at least one common zone are not permitted to communicate using the fabric. See also zoning.

 zone alias

An alias for a set of port numbers or worldwide names (WWNs). Zone aliases can be used to simplify the entry of port numbers and WWNs. For example, "host" could be used as an alias for a WWN of 110:00:00:60:69:00:00:8a.

 zone configuration

The set of groups of fabric ports (F_ports) that define the zones for a given fabric. See also defined zone configuration, enabled zone configuration.

 zoned decimal format

A format for representing numbers in which the digit is contained in bits 4 through 7 and the sign is contained in bits 0 through 3 of the least significant byte; bits 0 through 3 of all other bytes contain 1's (hex F). For example, in zoned decimal format, the decimal value of +123 is represented as 1111 0001 1111 0010 1111 0011. See also packed decimal format.

 zone transfer

The act of a secondary name server obtaining domain information from a master name server.

 zone width

The number of positions to the left of the right margin in which to end words.

 zoning

In fibre-channel environments, the grouping of multiple ports to form a virtual, private, storage network. Ports that are members of a zone can communicate with each other, but are isolated from ports in other zones. See also zone.

 zoom

To progressively increase or decrease the size of a part of an image on a display or window.

 Z-order

In VisualAge RPG, the order in which controls are placed on other controls. This order determines the relationship between controls.

 z/OS

An IBM mainframe operating system that uses 64-bit real storage. See also Base Control Program.

 z/OS DCE

See z/OS Distributed Computing Environment.

 z/OS Distributed Computing Environment (z/OS DCE)

A set of technologies that are provided by the Open Software Foundation to implement distributed computing.

 z/OS.e

An IBM operating system for the IBM eServer product line that provides selected z/OS functions on some servers.

 z/OS file system (zFS)

A type of file system that resides in a Virtual Storage Access Method (VSAM) linear data set (LDS).

 z/OS Network File System

A base element of z/OS that allows remote access to z/OS host-processor data from workstations, personal computers, or any other system on a Transmission Control Protocol/Internet Protocol (TCP/IP) network that is using client software for the Network File System (NFS) protocol.

 zSeries

IBM enterprise servers based on z/Architecture.

 zSeries storage

Storage arrays and logical volumes (LVOLs) that are defined in the ESS as connected to zSeries servers. See also count-key-data storage.

 z/VM

A System z9 and zSeries operating system that acts as virtualization software. z/VM can virtualize all system resources, including processors, memory, storage devices, and communication devices. z/VM supports the concurrent operation of hundreds of operating system instances.

 z/VM virtual server

In z/VM, a guest virtual machine that a user can log on to.

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