> # Glossary

> ADO.NET

> The data access standard for the Microsoft .NET platform.

> ActiveX Data Objects (ADO)

> A high level object-oriented database API built on OLE DB.

> authentication

> The process of identifying a user, typically based on a user ID and password. Authentication ensures that the user is who they claim to be. See also client authentication, NTLM authentication, OS authentication, and user ID/password authentication.

> client authentication

> Client authentication uses the user ID and password of the user logged onto the system on which the driver is running to authenticate the user to the database. The database server depends on the client to authenticate the user and does not provide additional authentication. See also authentication.

> Client data sources

> Minimal ODBC, ADO, or JDBC data sources that store connection instructions to a SequeLink Server.

> client load balancing

> Client load balancing distributes new connections in a computing environment so that no one server is overwhelmed with connection requests.

> connection failover

> Connection failover allows an application to connect to an alternate, or backup, database server if the primary database server is unavailable, for example, because of a hardware failure or traffic overload.

> connection pooling

> Connection pooling allows you to reuse connections rather than create a new one every time a driver needs to establish a connection to the database. Connection pooling manages connection sharing across different user requests to maintain performance and reduce the number of new connections that must be created. See also DataDirect Connection Pool Manager.

> connection retry

> Connection retry defines the number of times the driver attempts to connect to the primary and, if configured, alternate database servers after an initial unsuccessful connection attempt. Connection retry can be an important strategy for system recovery.

> Database
> Management
> System (DBMS)

> A layer of software between the physical database and the user. The DBMS manages all access to the database.

> data store

> The storage device for data a user accesses, such as the data in a database or a file. A data store owns data and exposes its data in a tabular form as a rowset over a native data format. Data stores can include a full SQL DBMS, an ISAM file, or a text file or data stream.

> DataDirect Connection Pool Manager

> The DataDirect Connection Pool Manager is a component shipped with DataDirect SequeLink Client for JDBC that allows applications to use connection pooling.

> Distinguished Name (DN)

> A name that identifies an LDAP entry in an LDAP directory. See also Lightweight Directory Access Protocol (LDAP).

> DataDirect Spy

> DataDirect Spy is a component shipped with DataDirect SequeLink Client for JDBC for tracking JDBC calls at runtime. It passes calls issued by an application to an underlying JDBC driver and logs detailed information about the calls.

> DataDirect Test

> DataDirect Test is a menu-driven component shipped with DataDirect SequeLink Client for JDBC that helps you debug your applications and learn how to use the drivers. DataDirect Test displays the results of all JDBC function calls in one window, while displaying fully commented, Java JDBC code in an alternate window.

> isolation level

> An isolation level represents a particular locking strategy employed in the database system to improve data consistency. The higher the isolation level number, the more complex the locking strategy behind it. The isolation level provided by the database determines how a transaction handles data consistency.

> The American National Standards Institute (ANSI) defines four isolation levels:

> - Read uncommitted (0)
> - Read committed (1)
> - Repeatable read (2)
> - Serializable (3)

> J2EE

> J2EE (Java 2 Platform, Enterprise Edition) technology and its component-based model simplify enterprise development and deployment. The J2EE platform manages the infrastructure and supports the Web services to enable development of secure, robust and interoperable business applications.

> JDBC

> A data access API standard for Java-enabled applets, applications, or Web browsers.

> JNDI

> The Java Naming and Directory Interface (JNDI) is a standard extension to the Java platform, providing Java technology-enabled applications with a unified interface to multiple naming and directory services in the enterprise. As part of the Java Enterprise API set, JNDI enables seamless connectivity to heterogeneous enterprise naming and directory services. Developers can now build powerful and portable directory-enabled applications using this industry standard.

> JTA

> JTA (Java Transaction API) specifies standard Java interfaces between a transaction manager and the parties involved in a distributed transaction system: the resource manager, the application server, and the transactional applications.

> Kerberos authentication

> Kerberos is an OS authentication protocol that provides authentication using secret key cryptography. See also authentication and OS authentication.

> load balancing

> See client load balancing.

> Lightweight Directory Access Protocol (LDAP)

> A standard protocol for accessing and updating common directory information.

> locking level

> Locking is a database operation that restricts a user from accessing a table or record. Locking is used in situations where more than one user might try to use the same table at the same time. By locking the table or record, the system ensures that only one user at a time can affect the data.

> Microsoft .NET

> A set of Microsoft software technologies for connecting information, systems, and devices. Microsoft .NET enables software integration through the use of XML Web services as well as to other, larger applications using the Internet.

> Microsoft Management Console (MMC)

> A common console framework for management applications. SequeLink Manager requires MMC 1.1 or higher.

> middleware

> Software that mediates the communication between an application and a data store. The middleware provides an interface that manages the differences in the application's and the data store's data formats.

> NTLM authentication

> NTLM (NT LAN Manager) is an OS authentication protocol that provides security for connections between Windows NT clients and servers. See also authentication and OS authentication.

> ODBC

> Microsoft's Open Database Connectivity (ODBC) specification. The ODBC specification for an Application Programming Interface (API) allows applications to access multiple database systems using Structured Query Language (SQL). For detailed information on ODBC, refer to the Microsoft programming documentation on ODBC.

> OLE DB

> Microsoft's low-level specification for access to different data sources. OLE DB includes SQL capabilities as well as access to other types of data. For detailed information on OLE DB, refer to the Microsoft programming documentation on OLE DB.

> OS authentication

> OS authentication can take advantage of the user name and password maintained by the operating system to authenticate users to the database or use another set of user credentials specified by the application. By allowing the database to share the user name and password used for the operating system, users with a valid operating system account can log into the database without supplying a user name and password. See also authentication, Kerberos authentication, and NTLM authentication.

> resource adapter

> A resource adapter is a system-level software driver used by an application server to connect to an Enterprise Information Service (EIS). The resource adapter communicates with the server to provide the underlying transaction, security, and connection pooling mechanisms.

> Secure Sockets Layer (SSL)

> SSL is an industry-standard protocol for sending encrypted data over database connections. SSL secures the integrity of your data by encrypting information and providing SSL client/SSL server authentication. See also SSL client/server authentication.

> SequeLink
> administrator

> Typically, the person who configures, manages, and monitors the SequeLink environment.

> SequeLink Agent

> The SequeLink service that acts as a proxy to carry out configuration, management, and monitoring requests from the SequeLink Manager.

> SequeLink Client

> A SequeLink software component that can be installed on a client machine or on a Web/Application Server. The ODBC Client provides ODBC access; the JDBC Client provides JDBC access; the ADO Client provides ADO/OLE DB access; the .NET Client provides .NET access.

> SequeLink
> configuration file

> A file that contains configuration information for SequeLink services.

> SequeLink data sources

> Optional data sources stored on the SequeLink server containing service-specific instructions that affect how data is accessed by a connection. Centralizing this information on the server, instead of distributing it among hundreds of clients, provides easier management of your entire data access infrastructure.

> SequeLink for .NET Provider

> The data provider that is installed with the .NET Client to provide .NET access.

> SequeLink for ADO Data Provider

> The data provider that is installed with the ADO Client to provide ADO access.

> SequeLink for JDBC Driver

> The driver that is installed within the JDBC Client to provide JDBC access.

> SequeLink for ODBC Driver

> The driver that is installed within the ODBC Client to provide ODBC access.

> SequeLink
> Manager

> A tool that you can use to configure, manage, and monitor your SequeLink environment. The SequeLink Manager is provided as an MMC Snap-in on Windows, a command-line tool on Windows and UNIX, and an ISPF dialog tool on z/OS.

> SequeLink
> Manager
> Command-Line Tool

> A command-line tool supported on Windows and UNIX platforms that allows you to configure, manage, and monitor your SequeLink environment.

> SequeLink
> Manager for z/OS

> An ISPF panel tool supported on z/OS that allows you to configure, manage, and monitor your SequeLink Server for z/OS services locally from a z/OS machine.

> SequeLink
> Manager Snap-in

> A GUI-based tool supported on Windows platforms that allows you to configure, manage, and monitor your SequeLink environment. Before you can use the SequeLink Manager Snap-in remotely, you must add it to the MMC.

> SequeLink profile

> Predefined profiles that you can use for monitoring your SequeLink environment, such as viewing details about active services, viewing active sessions, and requesting information about traced events.

> SequeLink Server

> The SequeLink software component that is installed on the server to provide data access services from client applications to data stores.

> SequeLink service

> SequeLink provides the following service types:

> - SequeLink data access services handle data access requests from any SequeLink client. Multiple SequeLink data access services can run on the same SequeLink server. For example, SequeLink Server for Oracle and SequeLink Server for Microsoft SQL Server can run side-by-side on the same machine. Some data services come with an enhanced code page version in addition to the default version.
> - SequeLink Agent services act as a proxy to carry out configuration, management, and monitoring requests from any SequeLink Manager. The SequeLink Agent can service multiple SequeLink services on the same SequeLink server.

> SequeLink service template

> A template that contains predefined attributes for a particular service type, for example, Oracle9i. Some data services come with an enhanced code page version in addition to the default version.

> SQL

> Structured Query Language. A language used by relational databases to query, update, and manage data.

> SSL client/server authentication

> SSL works by allowing the client and server to send each other encrypted data that only they can decrypt. SSL negotiates the terms of the encryption in a sequence of events known as the SSL handshake. The handshake involves the following types of authentication:

> - SSL server authentication requires the server to authenticate itself to the client.
> - SSL client authentication is optional and requires the client to authenticate itself to the server after the server has authenticated itself to the client.

> See also Secure Sockets Layer (SSL).

> Sysplex cluster

> z/OS sysplex cluster technology allows multiple servers to work in a cluster to provide sufficient processing power and availability to handle disparate demands of clients.

> Workload Manager (WLM)

> WLM is a z/OS construct that provides services to manage workload distribution, balance workload, and distribute resources.