◄ BACK NEXT ►

RA
See repeat to address.

RACE
See receive-any control element.

RACF
See Resource Access Control Facility.

RACF database
A collection of interrelated or independent data items stored together without redundancy, to serve the Resource Access Control Facility (RACF).

RACF-protected
Pertaining to a resource that has either a discrete profile or an applicable generic profile. A data set that is RACF-protected by a discrete profile must also be RACF-indicated.

RACF report writer
A RACF function that produces reports on system use and resource use from information found in the RACF SMF records.

RACF segment
The portion of a RACF profile that contains basic information needed to define a user, group, or resource to RACF. Also called base segment.

RACHECK request
In RACF, the issuing of the RACHECK macro or the RACROUTE macro with REQUEST=AUTH specified. The primary function of a RACHECK request is to check a user's authorization to a RACF-protected resource or function. See also authorization checking, FRACHECK request, RACROUTE.

RACINIT request
In RACF, the issuing of the RACINIT macro or the RACROUTE macro with REQUEST=VERIFY or REQUEST=VERIFYX specified. A RACINIT request is used to verify the authority of a user to enter work into the system. See also RACROUTE.

rack
A free-standing structure or frame that can hold multiple servers and expansion units.

rack configuration list
A list of all of the equipment within the rack and the logic cards within the card enclosure.

rack stabilizer
A plate that holds the rack stable or steady when a device is pulled out for service.

RACL
See Random Automated Cartridge Loader.

RACROUTE
In RACF, a macro that provides a means of calling RACF to provide security functions. See also FRACHECK request, RACHECK request, RACINIT request.

RAD
See rapid application development.

radio button
A circle with text beside it that indicates a fixed set of choices from which only one can be selected. The circle is partially filled when a choice is selected.

radio frequency (RF)
An alternating current that generates an electromagnetic field when applied to an antenna. The generated electromagnetic field is suitable for wireless broadcasting and communications.

radix-tree index
In DB2 UDB for iSeries, an object that provides random access to rows in a database table. See also encoded-vector index.

RAI
See remote alarm indication.

RAIA
See receive-any input area.

RAID
See Redundant Array of Independent Disks.

RAID-5
The RAID method used to prevent data loss by distributing data and parity information across three or more disk units. Capacity equivalent to one disk unit is dedicated to parity information. With RAID-5 a parity set can withstand one disk unit failure.

rail
Hardware attached inside a rack to hold devices that are designated as installable in a rack. See also slide.

RAM
See random access memory.

random access
In COBOL, an access method in which the program-specified value of a key data item identifies the logical record that is obtained from, deleted from, or placed into a relative or indexed file.

random access memory (RAM)
Computer memory in which any storage location can be accessed directly.

Random Automated Cartridge Loader (RACL)
A cartridge loader that includes individual drives that can have their own facility to use an automated tape library.

random by key
A processing method for files in which the value in the key field identifies the records to be processed.

random by relative record number
A processing method for files in which relative record numbers identify the records to be processed.

randomization
The process of distributing schedule start times for different clients within a specified percentage of the schedule's startup window.

random number
A number obtained by chance. See also pseudorandom number.

random processing
A method of processing in which records can be read from, written to, or deleted from a file order requested by the program that is using them. See also consecutive processing, sequential processing.

range-clustered table (RCT)
A table whose data is tightly clustered across one or more columns in the table. Each record in the table has a predetermined offset from the logical start of the table, which allows rapid access to the data.

rank
An integer value that signifies the relevance of a given part to the results of a query. A higher rank signifies a closer match.

rapid application development (RAD)
An environment supported by the workbench in which a server project can be configured to repeatedly deploy a server configuration (that contains message flows and message sets) to the broker with a single toolbar button click.

rapid deployment tool
One of a set of tools to rapidly develop and deploy J2EE artifacts on the server and package the J2EE artifacts into the deployed EAR file. See also automatic application installation project.

Rapid Transport Protocol (RTP)
A connection-oriented, full-duplex transport protocol for carrying session traffic over High-Performance Routing (HPR) routes.

Rapid Transport Protocol connection (RTP connection)
A connection between two High-Performance Routing (HPR) nodes that may traverse one or more intermediate HPR nodes and links. The connection endpoints provide error recovery and adaptive rate-based flow control for the connection traffic, and nondisruptive switching of the underlying physical path in the case of route outage. The intermediate HPR nodes minimize their routing overhead using automatic network routing (ANR) protocols, which rely on header information to permit efficient source routing and prioritized transmission along the RTP connection.

RAR
(1) See route addition resistance.
(2) See resource adapter archive.

RAS
See Reusable Asset Specification.

raster pattern
A series of picture elements (pels) arranged in scan lines to form an image. The toned or untoned status of each pel creates an image. A digitized raster pattern is an array of bits. The on or off status of each bit determines the toned or untoned status of each pel.

rating bean
A logging bean used to log explicit user preferences of resources. The rating bean is used to log ratings to the lps_user_rating LikeMinds database table as well as the Feedback schema. Typically, a user specifies a rating of a particular item. The rating bean logs the rating, user, and item information to the appropriate database tables.

Rational Administrator
A Rational tool that enables integrations between Rational products. Use Rational Administrator to configure Rational projects, which store software testing and development information.

Rational ClearCase
A configuration management system designed to help software development teams manage the files and directories used to create software. ClearCase can be used to manage the development and build process, to enforce site-specific development policies, and to support parallel development.

Rational ClearQuest
A software development tool that is used to track defects and requests for changes and new features.

rational number
A real number that is the quotient of an integer divided by an integer other than zero.

Rational Rose
A visual modeling tool for designing and visualizing object-oriented and component-based applications.

Rational TestManager
A Rational tool designed to help software development and testing professionals track software testing information through all phases of the software development, test, and revision cycles.

Rational Unified Process (RUP)
Rational's online knowledge base of proven software-development principles. The RUP captures many of the best practices in modern software development in a form that can be tailored to a wide range of projects and organizations. The RUP includes Tool Mentors, which provide descriptions on how Rational Software tools can be used to support particular steps and activities.

Rational XDE
Rational XDE Professional, an eXtended Development Environment that has been designed for developers and is fully integrated into the IBM WebSphere Workbench, IBM WebSphere Studio Application Developer, and Microsoft Visual Studio .NET. Its capabilities include pattern engine support, Unified Modeling Language (UML) visualization and documentation support, code templates, and automatic or on-demand synchronization of code and models. XDE Professional includes Rational XDE Modeler, which allows users to communicate designs and patterns in UML. Using XDE Modeler, team members can create semantically rich models for architecture, business needs, design, reusable assets, and management-level communication, which can then be used to generate working code. Developers can round-trip engineer changes, and architects can see whether architectural changes are required. Rational RequisitePro is integrated with XDE through Integrated Use Case Management.

raw metrics
Measures of person, document, and repository activity, such as the number of documents a person has authored in a category, the number of links to a document, and so on. Raw metrics are also known as usage statistics.

RBA
See relative byte address.

RBR
See rollback required.

RBS
See robbed-bit signaling.

RC
A REXX special variable set to the return code from any executed host command or subcommand. It is also set to the return code when the conditions ERROR, FAILURE, and SYNTAX are trapped.

RC5
An encryption technology for use in wireless clients and servers.

RCB
See record control byte.

RCD
See read cache device.

RC message
Recovered message; that is, an IP message that was copied from the control queue of an inoperable or closed ASP via the recover command.

RCMS
See remote change management server.

RCP
See rich client platform.

RCS
See remote console.

RCT
(1) See range-clustered table.
(2) See resource control table.

RDB
See relational database.

RDB directory
The directory where remote databases in the network are registered. Information in a directory tells the system which communications parameters to use to connect to a remote database. The RDB directory also contains the name of the local database.

RDBMS
See relational database management system.

RDBMS catalog
In the Information Catalog Center, a collection of tables that contains descriptions of SQL objects, such as tables, views, and indexes, maintained by an RDBMS. See also system catalog.

RDBMS Interface Module (RIM)
The module in the distributed object database that contains information about the installation of the relational database management system (RDBMS).

RDBNAM
See relational database name.

RDM
See resource definition macro.

RDN
See relative distinguished name.

RDO
See resource definition online.

RDSA
See read-only dynamic storage area.

RDT
See resource definition table.

RE
See remote extension.

read access list
In Notes, a list that restricts a form so that only specified users can read documents created from the form. Use the reader's field to control access on a document-by-document basis.

readahead prefetching
A method of prefetching pages by looking ahead in a scan, which results in asynchronous retrieval of pages even though those pages are not located sequentially on disk. See also list prefetch, sequential prefetch.

read authority
(1) An authority subset that allows the user to read entries in an object. The system-recognized identifier is *R. *R authority combines object operational authority and read authority.
(2) A data authority that allows the user to look at the contents of an entry in an object.

read cache device (RCD)
A volatile solid-state disk that is optimized for use as memory for the extended adaptive cache.

reader
(1) In RJE, a program that reads jobs from a database file or interactive display station and sends them to the host system.
(2) In Lotus Workflow, a person or group with reader access to documents in a job. Readers can have access to the documents in the binder for a single activity or for all activities in a job, depending on the process definition.
(3) An internal program that reads jobs from an input device or a database file and places them on a job queue.

reader access
An access level with which users can only read documents.

read/execute authority
An object authority that allows the user to read entries in an object, run a program, and search a library or directory. Read/execute authority combines object operational authority, read authority, and execute authority. The system-recognized identifier is *RX.

read-from-invited-program-devices operation
An input operation that waits for input from any one of the invited program devices for a user-specified time. See also read-from-one-program-device operation.

read-from-one-program-device operation
An input operation that will not complete until the specified device has responded with input. See also read-from-invited-program-devices operation.

read integrity
An attribute of a read request, which ensures the integrity of the data passed to a program that issues a read-only request. CICS recognizes two forms of read integrity: consistent and repeatable. See also dirty read, repeatable, consistent.

read intent
The type of access intent that subsystems use to read data from a database.

read-only
Pertaining to data that can be read but cannot be modified.

read-only access
An access level that permits a user or an application to read a document or record but not to update it.

read-only dynamic storage area (RDSA)
The key-0 storage area for all reentrant programs and tables below the 16MB boundary.

read-only memory (ROM)
Memory in which stored data cannot be changed by the user except under special conditions.

read-only mode
A document state that allows a Notes user to read but not modify a document. To modify a document, a user must have Editor access (or higher) to the database or be the document's author.

read operation
An input operation that obtains data from a file or device and passes it to a program.

read stability (RS)
(1) An isolation level that locks only the rows that an application retrieves within a transaction. Read stability ensures that any qualifying row that is read during a transaction is not changed by other application processes until the transaction is completed, and that any row changed by another application process is not read until the change is committed by that process. Read stability allows more concurrency than repeatable read, and less than cursor stability. See also cursor stability, repeatable read, uncommitted read.
(2) In DB2 UDB for iSeries, an isolation level that does not completely isolate an application process from all other application processes that are running concurrently. At the read stability level, an application that issues the same query more than once might read additional rows (phantom rows) that were inserted and committed by an application process that is running concurrently. See also repeatable read.

read token
The authorization key embedded in a READ PERMISSION DB DATALINK column value, returned as a simple column value or by using the scalar functions DLURLCOMPLETE or DLURLPATH. A read token is required for reading a file referenced in a READ PERMISSION DB DATALINK column.

read/write authority
An object authority that allows the user to add, change, delete, and read entries in an object. Read/write authority combines object operational authority, read authority, add authority, update authority, and delete authority. The system-recognized identifier is *RW.

read/write/execute authority
An object authority that allows the user to add, change, delete, and read execute entries in an object, run a program, and search a library or directory. Read/write/execute authority combines object operational authority, read authority, add authority, update authority, delete authority, and execute authority. The system-recognized identifier is *RWX.

read/write head
The data sensing and recording unit of the diskette drive or tape drive.

ready
Pertaining to a status where all the loaded and mounted image catalog entries are available for use by the active virtual optical device. Any image catalog entry with a status of unloaded is not available for use by the virtual optical device. The image catalog can be made ready by using the LODIMGCLG (Load Image Catalog) command with OPTION(*LOAD).

Ready for IBM Tivoli software
Pertaining to a product that has passed rigorous product certification testing to ensure that the product delivers seamless integration with Tivoli technology management solutions and provides true end-to-end technology management functionality. A product that has passed this certification testing carries the Ready for IBM Tivoli software logo.

ready queue
A MERVA queue used by SWIFT Link to collect SWIFT messages that are ready for sending to the SWIFT network.

ready to send
A hardware handshake or signal that is sent by a device to indicate that it is ready to send data.

realization
A relationship that exists between two model elements when one of them must realize, or implement, the behavior specified by the other.

realize
In the Web diagram editor, to associate a node with an actual resource by creating that resource or by editing the node's path so that it points to an existing resource. See also unrealized.

realizes relationship
(1) A list of the abstract objects realized by the physical expression. For example, the modeled classes (abstracts) realized by a component (physical expression).
(2) The physical expression of an abstract object.

realm
(1) A grouping of customers that organizes customer information and, in some cases, controls access to that information. Customers can be grouped by region, by company, by a division within a company, or by some other logical grouping.
(2) A collection of resource managers that honor a common set of user credentials and authorizations.
(3) In the Kerberos protocol, the set of principals for which a specific key distribution center (KDC) is the authenticating authority.

realm name
The machine name of a user registry.

realm trust
The Kerberos protocol either searches the configuration file to determine realm trust or by default looks for trust relationships within the realm hierarchy. Using Trusted realms in network authentication service allows you to bypass this process and creates a shortcut for authentication. Realm trust can be used in networks where realms are in different domains. For example, if a company has one realm at NY.myco.com and another at LA.myco.com, then you can establish trust between these two realms. If two realms trust each other their associated KDCs must share a key. Before creating a shortcut, you must set up the KDCs to trust each other.

real object
An object that represents an actual resource.

real resource
(1) In VTAM, a resource identified by its real name and its real network identifier.
(2) In the NetView Graphic Monitor Facility, an individual network resource represented by a real object.

real storage
The main storage in a virtual storage system. Physically, real storage and main storage are identical. Conceptually, however, real storage represents only part of the range of addresses available to the user of a virtual storage system.

real-time
Pertaining to the processing of data by a computer in connection with another process outside the computer according to time requirements imposed by the outside process. (I)(A)

real time
The processing of information that returns a result so rapidly that the interaction appears to be instantaneous.

real-time analysis (RTA)
In CICSPlex SM, a function that provides the automatic notification of requested error conditions and all aspects of a resource's status. The notifications appear in console messages, or generic NetView for OS/390 alerts, or both.

real-time gross settlement system (RTGS)
A payment system that settles, in real time, individual payments across central bank accounts. Payments must be secured by funds at the time the payment is made.

real-time replication
See synchronous replication. See also asynchronous replication.

Real Time Streaming Protocol (RTSP)
A protocol for streamed multimedia data over IP networks. Generally, RTSP offers services similar to a video store with delivery services, a VCR, or cable television. "VCR style" control functionality includes pause, fast forward, reverse, and absolute positioning.

Real-Time Transport Protocol (RTP)
A protocol that provides end-to-end network transport functions suitable for applications transmitting real-time data, such as audio, video or simulation data, over multicast or unicast network services.

reason code
A return code that describes the reason for the failure or partial success of a Message Queue Interface (MQI) call.

reassembly
In OSI, a function performed by an (N)-entity to map multiple (N)-protocol-data-units into one (N)-service-data-unit. Reassembly is the opposite of segmenting. See also segmenting.

reassign
To mark a disk sector as damaged. The marked disk sector points to another sector location where the data from the damaged sector is moved.

reassignment
The act of assigning a Lotus Workflow activity to a different person from the one who claimed the activity. Depending on the process definition, job owners and activity owners can reassign activities.

reattach
In cross-site mirroring, to reassociate the mirror copy with its production copy after user operations on the mirror copy are complete. When the mirror copy is reattached, it is automatically synchronized to match the production copy again. All data on the mirror copy prior to when it is reattached to the production copy is cleared.

reattachment event
An event whose firing has caused an activity to be activated.

reattachment queue
A list of the reattachment events that have caused a particular activity to be activated. Each activity has a reattachment queue associated with it. The queue may be empty. Events remain on the reattachment queue until they are retrieved by the activity, or until a syncpoint occurs.

rebalance
To restripe and redistribute data across the available hard disks after a disk or disks have been removed from a file system.

rebase
A ClearCase operation that makes a development work area current with the set of versions represented by a more recent baseline in another stream, usually the project's integration stream or a feature-specific development stream.

rebind
(1) To request renewal of a lease from a server on a particular network.
(2) To create a package for an application program that was previously bound. For example, if an index is added for a table that is accessed by a program, the package must be rebound for it to take advantage of the new index. See also automatic rebind.

rebuild maintenance
A method of maintaining keyed access paths for database files. This method updates the access path only while the file is open, not when the file is closed; the access path is rebuilt when the file is opened. See also delayed maintenance, immediate maintenance.

recall
To access files that have been migrated from workstations to server storage.

recapture
In update-anywhere replication, to capture changes at a replica table and forward these changes to the master table or to other replica tables.

receive-any control element (RACE)
Type of control field held in the CICS receive-any pool set aside for VTAM receive-any operations. The number of RACEs maintained depends on the RAPOOL and MXT system initialization parameters and on the number of active tasks. See the CICS Transaction Server System Definition Guide or the CICS/VSE System Definition and Operations Guide for more information.

receive-any input area (RAIA)
Type of input area held in the CICS receive-any pool set aside for VTAM receive-any operations. The number of RACEs maintained depends on the RAPOOL and MXT system initialization parameters and on the number of active tasks. See the CICS Transaction Server System Definition Guide or the CICS/VSE System Definition and Operations Guide for more information.

receive exit
A type of channel exit program that is called just after the message channel agent (MCA) has regained control following a communications receive and has received a unit of data from a communications connection. See also send exit.

receive mode
A time during which the BSC adapter looks for synchronization characters, and stores the data characters in main storage.

receive not ready (RNR)
In communications, a data link command or response that indicates a temporary condition of being unable to accept incoming frames.

receive queue
In Q replication, a WebSphere MQ message queue that is used by a Q Apply program to receive transactions that are captured by a Q Capture program.

receiver
(1) In hardware, a functional unit that converts small electronic signals to signals that control a device.
(2) A defined role in WebSphere Commerce that receives inventory at the fulfillment center, tracks expected inventory records and ad hoc receipts for ordered products, and receives returned products as a result of customer returns. See also logistics manager.

receiver bean
In extended messaging, a message-driven bean or a session bean. A message-driven bean is invoked when a message arrives at a JMS destination for which a listener is active. A session bean polls a JMS destination until a message arrives, gets the parsed message as an object, and can use methods to retrieve the message data.

receiver chain
The journal receivers presently or previously attached to the same journal. Each journal receiver, except the first one, has a previous receiver that was attached before the current receiver. Each journal receiver, except the currently attached receiver, has a next receiver.

receiver chain break
A logical break in a receiver chain.

receiver channel
In message queuing, a channel that responds to a sender channel, takes messages from a communication link, and puts them on a local queue.

receiver directory
Summary information about the journal receivers that are or were attached to the specified journal and are still known to the system.

receive ready (RR)
In communications, a data link command or response that indicates that a station is ready to receive protocol data units. Receive ready also acknowledges receipt of protocol data units.

receive timeout
In data communications, a condition that occurs when no data is received in a given period of time.

receiving cross-domain key
In Cryptographic Support, a cross-domain key used to decrypt a data-encrypting key that was encrypted by another location.

recency, frequency, monetary (RFM)
A technique used to determine which customers are the best ones by examining how recently a customer has purchased (recency), how often they purchase (frequency), and how much the customer spends (monetary).

receptacle
A hollowed electrical fitting that contains the live parts of a circuit.

RECFMS
See record formatted maintenance statistics.

recipient address
A string of data that represents the address associated with the recipient of the message. The contents and format of the string are not defined by the mail server framework. The address type associated with the recipient address is assumed to define the contents of the recipient address field.

recipient history tree
A structure that represents the changes to the recipient list, so that a recipient can be traced back to the recipient entry in the original recipient list passed using the Create Mail Message application program interface (API).

Recognition Engine server
In WebSphere Voice Server, the software that carries out the speech recognition and forwards the results to the client. This consists of one 'Tsm router' and at least one 'tsmp' and one 'engine'.

recognition profile
In the 3270 Terminal Services tool, a list of the identifiers that uniquely identify the state of a screen, that is, the set of conditions that apply to the screen at the time the screen was imported from the host. Each screen state needs to be uniquely defined in its own recognition profile.

recognition table
In the 3270 terminal services development tool, the table that appears in the screen editor and provides a screen definition view and a recognition profile view of the screen that was imported.

recombining
In OSI, a function performed by an entity that is the reverse of splitting.

Recommendation X.21 (X.21)
A document, CCITT Recommendation X.21, that outlines standards for a general-purpose interface between data terminal equipment (DTE) and data circuit-terminating equipment (DCE) for synchronous operations on a public data network.

Recommendation X.21 bis
A document, CCITT Recommendation X.21 bis, that outlines standards for the interface between data terminal equipment (DTE) and V-series data circuit-terminating equipment (DCE) for synchronous operations on a public data network.

Recommendation X.31
A document, CCITT Recommendation X.31, that outlines standards for the X.25 protocol over integrated services digital networks (ISDNs).

RECON data sets
See recovery control data sets.

record
(1) The storage representation of a single row of a table or other data.
(2) A group of related data, words, or fields treated as a unit, such as one name, address, and telephone number.
(3) In COBOL, the most inclusive data item. The level-number for a record is 01. A record can be either an elementary item or a group item.

record address file
In RPG, an input file that indicates which records are to be read from another file and the order in which the records are to be read.

record area
In COBOL, a storage area in which a record described in a record description entry in the File Section is processed.

record control byte (RCB)
In multileaving telecommunications access method (MTAM), a control character used to identify each record type within a transmission block.

record description entry
In COBOL, the total set of data description entries associated with a particular record.

recorded session
In LearningSpace - Virtual Classroom, a session, recorded by an instructor, that a participant can then watch. Only those who attend a session may play back a recorded session. A recorded session appears in a separate window that includes controls for playing, pausing, and stopping the session.

recorded telephone conference call
In Sametime, a telephone conference call that was scheduled as part of a Sametime meeting and recorded. After the meeting has finished, users can dial the access number to listen to the recorded call.

record format
A named part of a file that identifies records of a specified record format description.

record format definition
In IDDU, information that describes the arrangement or layout of fields in a record. A record format definition resides in a data dictionary.

record format description
A description of the characteristics of the fields (for example, type and length) and the arrangement of the fields in a record created by the user.
record formatted maintenance statistics (RECFMS)
A statistical record built by an SNA controller and usually solicited by the host.

record ID code
See record identification code.

record identification code (record ID code)
Characters placed in a record to identify the record format.

record identifier (RID)
A 3-byte page number followed by a 1-byte slot number that is used internally by DB2 to uniquely identify a record in a table. The RID contains enough information to address the page in which the record is stored. See also row identifier.

record identifier pool (RID pool)
In DB2 Universal Database for z/OS and OS/390, an area of main storage above the 16-MB line that is reserved for sorting record identifiers during list prefetch processing.

record identifying indicator
An indicator that identifies the record just read.

recording
The information from performance snapshots that can be viewed at a later time.

recording activity monitor
An object created by the Activity Monitor to record monitor data for database activities. The recorded data can be viewed at a later time.

record key
(1) In COBOL, a key field whose contents identify a record within an indexed file.
(2) In RPG, all the key fields defined for the record type.

record layout
In AFP Utilities, a part of the printout format definition that defines how each field of a database file record is formatted and printed by the print format utility.

record length
The sum of a length of all the columns in a table, which is the length of the data as it is physically stored in the database. Records can be fixed or variable in length, depending on how the columns are defined. If all columns are fixed-length columns, the record is a fixed-length record. If one or more columns are varying-length columns, the record is a varying-length column.

record-level specifications
Data description specifications coded on the same line as a record format name or on lines immediately following a record format name (until the first field is specified).

record-level subscriber (RLS)
An attribute of a user record that specifies which endpoints are subscribed to the user record.

record name
In COBOL, a user-defined word that names a record described in a record description entry in the Data Division of a COBOL program.

record number
In COBOL, the ordinal number of a record in the file whose organization is sequential.

record relocation vector table (RRV table)
A table that maps a note's note ID to the position of the note in the database. Each Notes database contains an RRV table.

record selection
The process of selecting particular records from a file and including the information from the records, for example, in a report.

record separator
In BSC, a control character used to indicate the end of one record and the beginning of another.

record type
The classification of records in a file. Records of the same type have the same fields in the same order. For program-described files, these records have record identification codes; for externally described files, the records have the same record format name.

recoverability
(1) The degree or extent to which the system can be restored to an operational condition after a system failure.
(2) The ability of a system to continue processing without loss of data when an unplanned interruption occurs.

recoverable in-doubt structure (RIS)
In DBCTL, an area constructed for each unit of recovery when a failure occurs. Each RIS is written to the IMS log. RIS contents include the recovery token, the changed data records, and the identity of the data block that cannot be accessed because of unresolved in-doubts.

recoverable log
A database log in which all log records are retained so that, in the event of a failure, lost data can be recovered during forward recovery. See also circular log.

recoverable resource
A resource that can be modified only in accordance with sync point protocols

recoverable service element (RSE)
A set of DBCTL subsystem identifiers of equivalent DBCTL subsystems, their associated job names, and the specific APPLIDs of the CICS systems that will use them. RSEs are defined by CICS resource definition macros and are held in the recoverable service table (RST). See also equivalent, recoverable service table.

recoverable service table (RST)
CICS control table used for IMS/ESA DBCTL support. The RST consists of recoverable service elements (RSEs), which define the DBCTL subsystems to which each CICS system can connect. See also equivalent, recoverable service element.

recovery
(1) The process of rebuilding databases after a system failure.
(2) The process of rebuilding a database or table space that has become unusable because of hardware or software failure, or both. The process includes by restoring a backup image and may include rolling database logs forward in time.
(3) The restoration of resources following an error.
(4) In Backup Recovery and Media Services, the process of locating and restoring data in the event of partial or total data destruction. The recovery service automatically locates the correct media to be restored based on user-defined media management and recovery requirements.
(5) The process of returning the system to a state from which operation can be resumed.

recovery control data sets (RECON data sets)
Dual recovery control data sets in which Data Base Recovery Control automatically records information about logging activity and events that might affect the recovery of databases. Both data sets contain identical information, and so are usually referred to as one - the RECON. DBRC selects the correct data sets to be used by a recovery utility.

recovery domain
A subset of nodes in a cluster that are grouped together for a common purpose, such as rebuilding databases after a system failure. A domain represents those nodes of the cluster where cluster resource exists.

recovery library
The library containing information related to recovery of database operations from system failures. Named QRECOVERY.

recovery log
(1) See database log.
(2) In WebSphere MQ for z/OS, data sets containing information needed to recover messages, queues, and the WebSphere MQ subsystem. WebSphere MQ for z/OS writes each record to a data set called the active log. When the active log is full, its contents are off-loaded to a DASD or tape data set called the archive log.

recovery log data set (RLDS)
A log data set that contains only the log records that are required for database recovery.

recovery manager
CICS resource recovery mechanism that provides a CICS resource manager, for example file control, with more flexibility than the DWE two-phase commit support for syncpoint and backout processing.

recovery pending (RECP)
The state of the database or table space when it is restored from a backup. While the database or table space is in this state, its data cannot be accessed.

recovery point
In the CICS backup-while-open facility, the latest point, on the CICS forward recovery log series for this data set, from which forward recovery can start and restore any image copy taken at that point to a consistent state. The recovery point is held as a time that can be converted to a position on the forward recovery log.

recovery policy
In Backup Recovery and Media Services, a policy that defines the default controls and values to be used in recovery operations.

recovery routine
A routine that is entered when an error occurs during the performance of an associated operation. It isolates the error, assesses the extent of the error, and attempts to correct the error and resume operation.

recovery termination manager (RTM)
A program that handles all normal and abnormal termination of tasks by passing control to a recovery routine associated with the terminating function.

recovery token
(1) A 16-byte unique identifier that is created by CICS (and passed to DBCTL) for each LUW. Its lifetime is the same as the LUW. The first 8 bytes are the CICS APPLID (in an XRF environment, this is the generic APPLID) and the second 8 bytes are a unit of recovery ID. (CICS creates a unit of recovery ID for every LUW.) DBCTL validates the recovery token to protect against duplication of units of recovery. The DBCTL operator can display the recovery token and it is also displayed in a number of CICS and IMS messages. See also pseudorecovery token.
(2) In DB2 Universal Database for z/OS and OS/390, an identifier for an element that is used in recovery (for example, NID or URID).

RECP
See recovery pending.

recursion
A programming technique in which a program or routine calls itself to perform successive steps in an operation, with each step using the output of the preceding step.

recursion cycle
The cycle that occurs when a fullselect within a common table expression includes the name of the common table expression in a FROM clause.

recursion level
The position of a program in a call stack. The first occurrence of a program in a job has a recursion level of 1, the second occurrence of the same program has a recursion level of 2, and so on.

recursive
Pertaining to a program or routine that calls itself after each run until it is interrupted.

recursive common table expression
A common table expression that refers to itself in a FROM clause from the fullselect. Recursive common table expressions are used to write recursive queries.

recursive mutex
A read/write lock that is acquired again by the owning thread.

recursive procedure
An active procedure that can be called from within itself or from within another active procedure.

recursive program
A program that can call itself, or be called by another program, and repeat indefinitely until a specified condition is met.

recursive query
A fullselect that uses a recursive common table expression.

redirection URL
A URL used in a URL command to indicate the page that should be sent to the customer upon completion of the command.

rediscovery
A type of discovery in which a program finds resources that were moved and updates the record of their location, including the location of resources that were deleted. For example, resources that were previously discovered, but are no longer found, are deleted.

redo
In DB2 Universal Database for z/OS and OS/390, a state of a unit of recovery that indicates that changes are to be reapplied to the DASD media to ensure data integrity.

REDO
The DEDB process in the second phase of a two-phase commit process if the chosen action is COMMIT. For DEDBs, if phase two action is COMMIT, the changes are written to the database using REDO, because the DEDB changes have only been made in main storage. If the action is BACKOUT, no changes are required to the database because the updates are still in main storage. The process applied is called UNDO. REDO is also used to refer to the action required for committed DEDBs during emergency restart of IMS, DL/I, or SQL/DS.

reduce
To free up enough space such that you can delete a volume from the database or recovery log. See also extend.

reduced instruction set computer (RISC)
A computer that uses a small, simplified set of frequently used instructions for rapid processing. See also complex instruction set computer.

Redundant Array of Independent Disks (RAID)
A collection of two or more disk physical drives that present to the host an image of one or more logical disk drives. In the event of a single physical device failure, the data can be read or regenerated from the other disk drives in the array due to data redundancy.

reentrable
Pertaining to a module that is designed for concurrent execution by multiple tasks. If a reenterable module modifies its own data areas or other shared resources in any way, it must use appropriate serialization methods to prevent interference between using tasks. See also quasi-reentrant.

reentrance
A situation where a thread of control attempts to enter a bean instance again.

reentrant
The attribute of a program or routine that allows the same copy of the program or routine to be used concurrently by two or more tasks.

refactor
To transform a program, for example by renaming a package or method, while preserving its behavior.

reference
(1) Logical names defined in the application deployment descriptor that are used to locate external resources for enterprise applications. At deployment, the references are bound to the physical location of the resource in the target operational environment.
(2) Single direction, one-to-one association between a root or child component and another root component. Contrast with link. See also link.
(3) In VisualAge RPG, information from a physical source file that may be extracted at build time. Any changes made to the original source must be recompiled to reflect the changes at run time.

reference code
A group of characters that identifies the machine status or a specific error condition.

reference code translation table
An object that contains reference code and field-replaceable-unit (FRU) code records. These records are used to report hardware errors and do problem analysis and resolution. The system-recognized identifier for the object type is *RCT.

referenced window record
In DDS, a record containing the WINDOW keyword that identifies the name of a window definition record.

reference format
A format that provides a standard method for describing COBOL source programs.

reference frame
See information frame.

reference line
In Business Graphics Utility, a straight line parallel to either the vertical or horizontal axis relative to which data values are plotted on a chart. Sometimes called a translated axis line.

reference message
A message that refers to a piece of data that is to be transmitted. The reference message is handled by message exit programs, which attach and detach the data from the message so allowing the data to be transmitted without having to be stored on any queues.

reference model
(1) A model that contains model information from one referenced component. Reference models are kept as separate models and are included by reference into code projects.
(2) In the context of Tivoli software, the model configuration for a system, or set of systems, that is used to maintain consistent configurations in a distributed environment.

reference modification
In COBOL, a method of establishing and referring to a data item by specifying a leftmost character position and length within a character string.

reference modifier
In COBOL, the leftmost character position and the length of a character string used to establish and refer to a data item.

reference modify
To establish and refer to a COBOL data item by specifying a leftmost character position and length within a character string.

reference phrase
The text that is highlighted and preceded by a single-character input field used to signify the existence of a hypertext link.

reference set
The amount of real storage required so that minimal (almost zero) virtual paging occurs. It is the total amount of real storage required to process the most frequently used sequence of instructions and data for a given set of transactions performing defined tasks, without causing any virtual storage paging operations.

reference store
An online store that contains fully functional code for selected features of an online store, for example, auctions. Reference stores are designed to be used by store developers as code samples of the highlighted features.

reference-valued business object
A business object that contains data values only for its key attributes. See also foreign key attribute, full-valued business object.

referential constraint
The requirement that the nonnull values of a designated foreign key are valid only if they also appear as values of the primary key of the parent table. The referential constraint is always defined from the perspective of the dependent file. See also relationship, unique constraint, informational constraint.

referential cycle
(1) A set of referential constraints such that each table in the set is a descendent of itself.
(2) See constraint cycle.

referential integrity
(1) The state of a database in which all values of all foreign keys are valid. Maintaining referential integrity requires the enforcement of a referential constraint on all operations that change the data in a table where the referential constraints are defined.
(2) In Extensible Markup Language (XML) tools, the condition that exists when all references to items in the XML schema editor or DTD editor are automatically cleaned up when the schema is detected or renamed.
(3) The condition that exists when all intended references from data in one column of a table to data in another column of the same or a different table are valid.

referential structure
In DB2 Universal Database for z/OS and OS/390, a set of tables and relationships that includes at least one table and, for every table in the set, all the relationships in which that table participates and all the tables to which it is related.

referral
(1) A record that shows number of times a third-party business or Web site has referred customers to the Web site. Referrals can be measured for recognition purposes through various techniques including clickstream analysis, clickthrough rates, affiliate marketing services, and surveys.
(2) A way for servers to refer clients to additional directory servers. With referrals you can: distribute namespace information among multiple servers, provide knowledge of where data resides within a set of interrelated servers, and route client requests to the appropriate server.
(3) In the Lightweight Directory Access Protocol (LDAP), a pointer from one LDAP directory server to another.

referral number
The phone number to which calls are routed, when call forwarding is active.

reflective marker
In hardware, reflective material placed on magnetic tape to indicate the beginning or ending of the recording area.

refresh pack
A cumulative collection of fixes that contains new functions. Full regression testing is performed on refresh packs. See also fix pack, interim fix, manufacturing refresh.

refund
In WebSphere Commerce Payments, the credit amount in the smallest denomination of the particular currency used to place the order.

region
(1) A contiguous area of virtual storage that have common characteristics and that can be shared between processes.
(2) A physical instance of a CICS server.
(3) In MVS, a variable-size subdivision of virtual storage that is allocated to a job step or system task. CICS Transaction Server runs in an MVS/ESA region, usually referred to as the CICS region.

region-remote
A term used in early releases of CICS to refer to a CICS system in another region of the same processor. It can be taken to refer to a system that is accessed through an IRC (MRO) link, rather than through an SNA LU6.1 or LU6.2 link.

register
(1) To insert authorization and authentication information into binding information.
(2) In SQL replication, to define a DB2 Universal Database table, view, or nickname as a replication source.
(3) In the hierarchical file system, to make an underlying file system and the specific functions it supports known to the application programming interface layer and accessible to user applications.
(4) A storage area having a specified storage capacity and usually reserved for a special purpose.

registered customer
(1) A customer who is registered with a store. To register, a customer provides personal information to the WebSphere Commerce system, such as an e-mail address.
(2) In WebSphere Commerce, a defined role that allows the reseller to shop in the marketplace. Resellers must first register in the marketplace and be approved by the Seller Administrator in order to attain the Registered Customer role.

registered enterprise-unique identifier
A name given to an entire network that makes the network unique among other networks, including IBM networks. New users are requested to register the network name with IBM if they plan to communicate with IBM networks (for PTF information, for example).

registered filter
A filter that allows more than one active filter for alerts and problem logs. When a filter is registered, the system can send notification of events to a data queue. Registered filters behave slightly different than filters exposed through the network attributes or system value commands.

registered name
In a Tivoli environment, the name by which a particular resource is registered with the name registry when it is created.

registered user
A portal user who has a user ID and password for logging in to the portal. Compare with anonymous user and authenticated user.

registration
(1) In X.25, the process used between a DTE and a DCE to establish an agreement on which optional user facilities will be in effect. For example, the DTE can request that the DCE agree to or stop a previous agreement for an optional user facility. Also, a DCE can indicate which optional user facilities are available or which optional user facilities are currently in effect. The negotiation is accomplished through the exchange of registration packets.
(2) The identification of a structured content type to be available for authoring within a current project.
(3) In OSI, the process of obtaining identifiers for objects from the appropriate naming authorities. Registered identifiers should be obtained for the following objects, which relate to OSI Communications Subsystem operations: (a) NSAP addresses, (b) DTE addresses, (c) abstract syntaxes, (d) application contexts, and (e) application entities.
(4) In SQL replication, the process of registering a DB2 Universal Database table, view, or nickname as a replication source. See also subscription.

registration facility
A service that provides storage and retrieval operations for OS/400 and non-OS/400 exit points and exit programs.

registration facility repository
The repository that contains information about the OS/400 and non-OS/400 exit points and exit programs.

registration process
In replication, the process of defining a replication source.

registry
(1) A repository that contains access and configuration information for users, systems, and software.
(2) In a Microsoft Windows operating system, a database that contains system configuration information regarding the user, the hardware, and the programs and applications that are installed. Windows operating systems refer to the registry during operation.

registry database
In a z/OS or OS/390 environment, a database of security information about principals, groups, organizations, accounts, and security policies.

Registry Editor
In Windows, the program item that allows the user to edit the registry.

registry hive
In Windows systems, the structure of the data stored in the registry.

regular comma