R

RAF

(robot application function) (n.) A function that can be used in robot filter configuration files. User-defined robot application functions are also called plug-in functions. These functions are invoked by directives.

RAM

(random access memory) (n.) The physical semiconductor-based memory in a computer.

RAR file

(resource adapter archive) (n.) A Java^TM archive (JAR) file that contains a resource adapter module, also called a connector module.

RC2

(n.) A variable key-size block cipher by RSA Data Security.

rc.2.d file

(n.) (UNIX only) A file on UNIX machines that describes programs that are run when the machine starts. This file is also called /etc/rc.2.d because of its location.

RC4

(n.) A stream cipher by RSA Data Security. Faster than RC2.

RD

See resource description.

RDB

(n.) Relational database.

RDBMS

(n.) Relational database management system.

RDF

(Resource Description Framework) (n.) A standard for defining the kind of data that an XML file contains. Such information can help ensure semantic integrity, for example, by helping to make sure that a date is treated as a date rather than simply as text.

RDF schema

(n.) A standard for specifying consistency rules that apply to the specifications contained in an RDF.

RDM

See resource description message.

RDN

(relative distinguished name) (n.) The name of the actual entry itself, before the entry's ancestors have been appended to the string to form the full DN. Most RDNs consist of a single attribute type and value from the entry.

read-only bean

(n.) An entity bean that is never modified by an EJB^TM client. See also entity bean.

realm

(n.) A scope over which a common security policy is defined and enforced by the security administrator of the security service. Also known as a security policy domain or security domain. In the J2EE server authentication service, a realm is a complete database of roles, users (or principals), and groups that identify valid users of a web application or a set of web applications.

redirection

(n.) A mechanism by which clients accessing a particular URL are sent to a different location, either on the same server or on a different server. Redirection is useful if a resource has moved and you want the clients to use the new location transparently. Redirection is also used to maintain the integrity of relative links when directories are accessed without a trailing slash.

reentrant entity bean

(n.) An entity bean that can handle multiple simultaneous, interleaved, or nested invocations that will not interfere with each other.

reference

(n.) A reference to an entity that is substituted for the reference when the XML document is parsed. See entity reference.

reference deployment architecture

(n.) A deployment architecture that has been designed, implemented, and tested for performance. Reference deployment architectures are used as starting points for designing deployment architectures for custom solutions.

referential integrity

(n.) The mechanism that ensures that relationships between entries expressed by DN-valued attributes are maintained within the directory.

referral

(n.) When a server receives a search or update request from a client that it cannot process, the server sends back to the client a pointer to the Java Enterprise System Directory Server that can process the request.

referral hop limit

(n.) The maximum number of referrals that a client should follow in a row.

registry

(n.) An infrastructure that enables the building, deployment, and discovery of web services. It is a neutral third party that facilitates dynamic and loosely coupled business-to-business (B2B) interactions.

registry provider

(n.) An implementation of a business registry that conforms to a specification for XML registries (for example, ebXML or UDDI).

regular expression

(n.) A text string that uses special characters to represent ranges or classes of characters for the purpose of pattern matching.

relative distinguished name

See RDN.

relationship field

(n.) A virtual field of an entity bean having container-managed persistence; it identifies a related entity bean.

relaying

(n.) The process of passing a message from one messaging server to another messaging server.

remote interface

(n.) One of two interfaces for EJB 1.x and 2.x components. The remote interface defines the business methods callable by a client. See also home interface.

remove method

(n.) A method defined in the home interface and invoked by a client to destroy an EJB 1.x or 2.x enterprise bean.

renderer

(n.) A Java class that can render the output for a set of JavaServer Faces UI components.

rendering

(1) (n.) The process of converting content written in Abstract Markup Language (AML) to the appropriate device-specific markup language for a specific mobile device.

(2) (n.) The process of producing output for a client. See renderer.

rendering channel

(n.) A Portal Server Mobile Access channel that displays rendering content.

rendering engine

(n.) In Portal Server, converts AML to the language appropriate for a given mobile client.

rendering filter

(n.) The filter that passes content for conversion between the rendering engine and client.

render kit

(n.) A set of renderers that render output to a particular client. The JavaServer Faces technologyimplementation provides a standard HTML render kit, which is composed of renderers that can render HTML markup.

replica

(n.) A suffix on a directory server that is linked to one or more other suffixes through a replication agreement.

replica cycle

See replication cycle.

replica directory server

(n.) The directory that receives a copy of all or part of the data.

replica group

(n.) The servers that hold instances of a particular area of replication. A server can be part of several replica groups.

replication

(n.) The process of synchronizing data distributed across Directory Servers and rectifying update conflicts.

replication agreement

(n.) A set of configuration parameters that are stored on the supplier server and that identify the suffixes to replicate, the consumer servers to which the data is pushed, the times during which replication can occur, the DN and credentials used by the supplier to bind to the consumer, and how the connection is secured.

replication base entry

(n.) The DN of the root of a replicated area.

replication cycle

(n.) The interval during which update information is exchanged between two or more replicas. The replication cycle begins during an attempt to push data to or pull data from another replica or set of replicas and ends when the data has successfully been exchanged or when an error is encountered.

replication session

(n.) A session set up between two servers in a replica group to pass update information as part of a replication cycle.

request object

(n.) An object that contains page and session data produced by a client, passed as an input parameter to a servlet or a page created with the JavaServer Pages^TM technology

request-response messaging

(n.) A method of messaging that includes blocking until a response is received.

required attribute list

(n.) A list of required attributes for a specified object class. Required attributes are preceded by the keyword MUST.

required attributes

(n.) Attributes that must be present in entries using a particular object class. See also allowed attributes, attribute.

resource

(1) (n.) Any item on a network that can be identified by a URL, such as a web page, a document, or an FTP directory. A resource is often referred to informally as a document.

(2) (n.) Any URL, directory, or program that the server can access and send to a client that requests it.

(3) (n.) A program object that provides connections to systems, such as database servers and messaging systems.

resource adapter

(n.) A system-level software driver that is used by an EJB container or an application client to connect to an enterprise information system (EIS). A resource adapter typically is specific to an EIS. It is available as a library and is used within the address space of the server or client using it. A resource adapter plugs in to a container. The application components deployed on the container then use the client API (exposed by the adapter) or tool-generated high-level abstractions to access the underlying EIS. The resource adapter and EJB container collaborate to provide the underlying mechanisms-transactions, security, and connection pooling-for connectivity to the EIS. See also connector.

resource adapter module

(n.) A deployable unit that contains all Java interfaces, classes, and native libraries, implementing a resource adapter along with the resource adapter deployment descriptor.

resource calendar

(n.) A calendar associated with a resource such as a meeting room or equipment such as a notebook computer or overhead projector.

resource description

(n.) A list of attribute-value pairs associated with a resource through a URL. Agents can generate resource descriptions automatically or people can write resource descriptions manually. Once a repository of resource descriptions is assembled, the server can export the repository through resource description messages as a programmatic way for web agents to discover and retrieve the resource descriptions. Resource descriptions are stored in SOIF format.

resource description message

(n.) A mechanism to discover and retrieve metadata about network-accessible resources, known as resource descriptions.

resource invocation

(n.) An instance of a resource type running on a node. An abstract concept representing a resource that was started on the node.

resource manager

(n.) Provides access to a set of shared resources. A resource manager participates in transactions that are externally controlled and coordinated by a transaction manager. A resource manager typically is in a different address space or on a different machine from the clients that access it. Note: An enterprise information system (EIS) is referred to as a resource manager when it is mentioned in the context of resource and transaction management.

resource manager connection

(n.) An object that represents a session with a resource manager.

resource manager connection factory

(n.) An object used for creating a resource manager connection.

resource offering

(n.) In a Discovery Service, a resource offering defines associations between a piece of identity data and the service instance that provides access to it.

resource reference

(n.) An element in a deployment descriptor that identifies the component’s coded name for the resource.

response buffer

(n.) The Portal Server Mobile Access server response buffer stores large responses as separate smaller responses so that they fit limited device buffers.

response object

(n.) An object that references the calling client and provides methods for generating output for the client.

restart

(v.) To start the robot without deleting its state information, which causes the robot to start running in the same state in which it previously stopped. Opposite of a fresh start.

restore

(v.) To copy the contents of folders from a backup device to the message store. See also back up.

ResultSet object

(n.) An object that implements the java.sql.ResultSet interface. ResultSet objects are used to encapsulate a set of rows retrieved from a database or other source of tabular data.

resync interval

(n.) How often a connector checks a Identity Synchronization for Windows directory source for changes. This periodic check is efficient and only requires reading entries of users that have changed since the last check. The console expresses this value in milliseconds and provides 1000 (1 second) as a default.

retro changelog

(n.) Stores changes in the order of arrival on the local server and not in the order in which these changes were applied to the system. The retro changelog was not designed to function in a multimaster replication environment. Not the same as change log, as the retro changelog is not used in replication. Provides backward compatibility with Directory Server 4.

reusable component

(n.) A component created so that it can be used in more than one capacity, for example, by more than one resource or application.

reverse DNS lookup

(n.) The process of querying the DNS to resolve a numeric IP address into the equivalent gateway.

reverse proxy

(n.) A proxy that performs bidirectional URL rewriting and translation between clients and servers. Unlike a proxy, which exists at the client side, a reverse proxy exists at the server side of the network. In Java Enterprise System Portal Server, the reverse proxy exists in Java Enterprise System Portal Server Secure Remote Access Pack.

Rewriter

(n.) The Rewriter provides a Java class library for rewriting URL references in various web languages, such as HTML, Javascript, and XML, and in HTTP location headers (redirections). The Rewriter defines a Java Enterprise System Directory Server Access Management Edition service for storing rules that define how rewriting is to be done and the data to be rewritten. The Rewriter also includes an admin console module for editing these rules.

rewrite rule

(n.) A tool that the MTA uses to route messages to the correct host for delivery. Rewrite rules perform the following functions: (1) extract the host and domain specification from an address of an incoming message, (2) match the host and domain specification with a rewrite rule pattern, (3) rewrite the host and domain specification based on the domain template, and (4) decide which channel queue the message should be placed in. Also known as a domain rewrite rule.

RFC

(request for comments) (n.) A document series maintained by the Internet Engineering Task Force that describes the Internet suite of protocols and related experiments. Very few RFCs describe Internet standards, but all Internet standards are published as RFCs. See http://www.imc.org/rfcs.html.

RMI

(remote method invocation) (n.) A technology that allows an object running in one Java virtual machine to invoke methods on an object running in a different Java virtual machine.

RMI-IIOP

(n.) A version of RMI implemented to use the CORBA IIOP protocol. RMI over IIOP provides interoperability with CORBA objects implemented in any language if all the remote interfaces are originally defined as RMI interfaces.

RMIC

(n.) remote method invocation compiler.

robot

(n.) A program that finds all the resources located in a specific portion of a network.

robot application function

See RAF.

role

(1) (n.) An abstract logical grouping of users that is defined by the application assembler. When an application is deployed, the roles are mapped to security identities, such as users (principals) or groups, in the operational environment. See also user, group.

(2) (n.) In the J2EE server authentication service, an abstract name for permission to access a particular set of resources.

(3) (n.) In Java Enterprise System Directory Server Access Management Edition, a grouping that represents a selection of privileged operations. By applying the role to a user or a service, the principal can perform the operations. For example, by confining certain privileges to an Employee role or a Manager role and applying the role to a user, the user’s accessibility is confined to the privileges granted to it by the role. Roles are defined using access control instructions (ACIs).

(4) (n.) The function performed by a party in the development and deployment phases of an application developed using J2EE technology. The roles are application component provider, application assembler, deployer, J2EE product provider, EJB container provider, EJB server provider, Web container provider, Web server provider, tool provider, and system administrator.

role-based attributes

(n.) Attributes that appear on an entry because the entry possesses a particular role within an associated CoS template.

role mapping

(n.) The process of associating the groups or principals (or both), recognized by the container with security roles specified in the deployment descriptor. Security roles must be mapped by the deployer before a component is installed in the server.

rollback

(n.) Cancellation of a transaction. The point in a transaction when all updates to any resources involved in the transaction are reversed.

root

(1) (n.) (UNIX only) The most privileged user on UNIX machines. The root user has complete access privileges to all files on the machine.

(2) (n.) The outermost element in an XML document. The element that contains all other elements.

root DN

(n.) The DN of the Directory Manager.

Root DSE

(n.) An entry that is automatically generated by the Directory Server and is returned from a baseObject search with a DN that is empty (zero bytes long). The Root DSE provides information to clients about the server\qs configuration, such as a pointer to the subschema entry, a list of the DNs of the naming contexts held by the server, and a list of the LDAPv3 controls and extensions that the server supports. See also DSE.

root entry

(n.) The top-level entry of the DIT hierarchy.

root suffix

(n.) The parent of one or more sub suffix. A directory tree can contain more than one root suffix.

router

(n.) A system responsible for determining on which path network traffic will flow. A router uses a routing protocol to gain information about the network and algorithms to choose the best route based on several criteria known as a “routing matrix.” In Open Systems Interconnect terminology, a router is a Network Layer intermediate system. See also gateway.

routing

See message routing.

routing tables

(n.) The internal databases that hold the information about message originators and recipients.

row

(n.) A single data record that contains values for each column in a table.

RowSet object

(n.) An object that encapsulates a set of rows retrieved from a database or other source of tabular data. The RowSet object extends the java.sql.ResultSet interface, enabling the ResultSet object to act as a component based on the JavaBeans^TM component architecture.

RPC

(remote procedure call) (n.) A mechanism for accessing a remote object or service.

RTT

(round trip time) (n.) The elapsed time for transit of a signal over a closed circuit (from the server to the client and back). This delay is important in systems that require two-way interactive communication where the RTT directly affects the throughput rate. In the context of Java Enterprise System Directory Server, the RTT and the TCP window can have a significant impact on replication performance over a wide-area network. Also known as round-trip delay time.

rules

(n.) Logical tests applied to determine whether a condition is met. The robot uses rules as part of filters for determining types of content to index and in classification rules to determine what category to assign to a resource.