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General Technical Definitions

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

AD
Applications Development

ADT
Abstract Data Type - object oriented term

ANSI
American National Standards Institute - an organization for establishing voluntary industry standards.

API
Application Programming Interface - a set of program functions that calls that allow an application to make use of, or communicate with, an underlying program or system.

ASCII
American Standard Code for Information Interchange - a convention for representing alphanumeric information using digital data. ASCII is the collation sequence used by most computers with the exception of IBM and IBM-compatible computers. Contrast with EBCDIC character set.

Baud
When transmitting data, the number of times the medium's "state" changes per second. For example: a 2400-baud modem changes the signal it sends on the phone line 2400 times per second. Since each change in state can correspond to multiple bits of data, the actual bit rate of data transfer may exceed the baud rate.

BPR
Business Process Re-Engineering

Byte
A group of eight sequential bits that represents a letter, number, or symbol (i.e., character). Treated as a unit of data by a computer.

CASE
Computer-aided software engineering

Clustering
Clustering allows multiple hardware servers to act as a single system, enabling customers to spread software processing across servers to maximize performance, availability, and scalability. In addition, clustering can be used to minimize downtime by shifting workloads from one server to another in the event of system failure or scheduled service.

Codec
Any hardware device or algorithm that converts video or audio between uncompressed analog and compressed digital formats.

CMOS
Complementary Metal-Oxide Semiconductor

COM
Component Object Model - is the core object model in OLE - it helps the OS run distributed objects as a unified local application. Provides a software mechanism for ActiveX controls to communicate with one another on a desktop.

CORBA
Common Object Request Broker Architecture - a specification of the Object Management Group (OMG) which defines a distributed client/server middleware architecture with an open software bus on which objects from multiple vendors, running on different operating systems, can interoperate.

cryptographic checksum (message digest)
A mechanism which computes a value for a message packet (by using a secret key), based on the data it contains, and passes it along with the data to authenticate that the data has not been tampered with. The recipient of the data recomputes the crypto checksum passed with the data; if they match, it is 'probabilistic' proof the data was not tampered with during transmission.

DCE (OSF's)
Open Software Foundation's Distributed Computing Environment - a heterogeneous networking standard designed to make distributed computing as simple as host-based computing. It does it by providing a standrad set of DCE services on every platform including a DCE Remote Procedure Call (RPC) for standards-based secure communications, directory services (CDS), distributed time services, distributed file systems, and distributed security services (network encryption, single sign-on, and centralized privilege management).

D/COM
Distributed COM - allows for object (ActiveX) interoperability between machines and across networks (a distributed environment). Represents a homogeneous-system interoperability mechanism (single-vendor standard), unlike CORBA/IIOP (multi-vendor standard across heterogeneous systems).

DFD
Data Flow Diagram

DII
Dynamic Invocation Interface - allows CORBA objects dynamic creation and invocation of requests (consisting of an object reference, an operation, and a list of parameters) to distributed objects. The ORB applies the implementation (encapsulation) principle to the request.

disk affinity (function shipping)
Sending the request to the instance closest to the instance which owns the data.

Distributed Object
Self-contained packages that can operate across different operating systems, networks, languages, and hardware and they use an Object Request Broker (ORB) for interoperability.

DLL
Dynamic Link Library

DMPP
Distrbuted Memory Parallel Processing

DNA
Distributed interNet Applications Architecture (Microsoft Windows's)

DTP
Distributed Transaction Processing

DVD
Digital Versatile Disk

EDI
Electronic Data Interchange - set of specifications for ordering, billing, and paying for parts and services over private electronic networks.

EDIINT
The IETF EDI Working Group have created EDIINT, which combines the EDI standards set for transmission of transaction data with the internet protocol suite. EDI documents, either in traditional EDI formats such as ANSI X12 or EDIFACT can then be transmitted as SMIME attachments between applications over standard protocols. The group's initial focus is the SMTP email protocol.

ELA
Enterprise License Agreement

Encapsulation
Create transparent routines that can be used independently from their actual implementation so small changes made in common routines wont ruin someone else's code. No parts of a complex system should depend upon the internal details of another part. It allows program changes to be made reliably with a minimum of effort.

E-R Model
Entity-Relationship model which provides a clear overview of complex projects - Oracle Designer/2000.

ERD
Entity-Relationship Diagram

ERP
Enterprise Resource Planning

Ethernet
A kind of "local area network." It's pretty confusing because there are several different kinds of wiring, which support different communication speeds, ranging from 2 to 10 million bits per second. What makes an Ethernet an Ethernet is the way computers on the network decide whose turn it is to talk. Computers using TCP/IP are frequently connected to the Internet over an Ethernet.

FAQ
Either a frequently asked question, or a list of frequently asked questions and their answers. Many USENET newsgroups, and some non- USENET mailing lists, maintain FAQ lists (FAQs) so that participants don't spend lots of time answering the same set of questions.

FSIOP
File Serving Input/Output Processor

Frame Rate
The number of images per second displayed in a video stream. Approximately 24 frames per second (fps) is considered full-motion video.

Function Shipping
On a shared-nothing architecture ship function to CPU that has the data and only ship back the result data.

GUI
Graphical User Interface

HSM
Hierarchical Storage Management - its primary function is to enable efficient data migration with transparent accessibility and recall. Locally attached storage should be for active data only - inactive data should be automatically migrated to the storage management server's hard drive and down the storage hierarchy to less-expensive media (online to offline to archive - slower access, but less costly). The user should not be aware that his or her files have been migrated to nearline or offline storage.

ICX
Inter-Cartridge Exchange. An object bus that enables cartridges distributed across a network to communicate with each other. Uses both IIOP and HTTP protocols natively for this communication. It is implemented as a set of libraries and services which reside within the various computers that are attached to the network.

IDL
Interface Definition Language - a language-neutral interface that allows the cartridge to identify itself to other objects in a distributed system.

IETF
Internet Engineering Task Force - the organization principally responsible for the definition of most standards on the Internet.

IIOP
CORBA's Internet Inter-ORB Protocol - communication protocol between CORBA objects which uses the Internet (TCP/IP) as a backbone - message-based - less overhead than HTML because get bandwidth benefits.

Inheritance
Will help make application's user interface consistent - helps create GUI standards for application. Oracle Forms lets you create property classes for this which is a named list of properties and methods (triggers) - applied to an object and it will inherit all which make sense for it. These properties can be overridden or defaulted back if wanted. Multi-level inheritance (create a hierarchy of classes) is when a property class inherits values from another property class - the exitButton class could inherit properties from genericButton class. When inheriting objects you can copy or reference them - if copy then changes made to target will not change the source.

IS
Information Systems

ISO
The international Organization for Standardization; an organization that has defined a different set of network protocols, called the ISO/OSI protocols. In theory, the ISO/OSI protocols will eventually replace the Internet Protocol. When and if this will actually happen is a hotly debated topic.

ISV
Independent Software Vendor

Julian date
Any day that is measured by counting the number of days from an arbitrary zero day - Jan 1, 4713 B.C. at noon Greenwich time

LAN
Local Area Network

LDAP
Lightweight Directory Access Protocol - LDAP-based intelligent directory services store and deliver contact information, registration data, certificates, configuration data and server state information. The key benefits of LDAP are:
Leap Year
Year that is evenly divisible by 4 and if it’s a century (i.e. 1700), also evenly divisible by 4

LIMS
Laboratory Information Management System

Load Balancing
Client to server and server to server connection don't always have to follow the same route. The server can have multiple listeners on different machines which will distribute the connections. Evenly distribute incoming user connections across multiple parallel server instances.

LOB
Line of Business

MAPI
Mail/Messaging Application Programming Interface

MDDB
Multi-Dimensional Database - represents multi-dimensional data as aggregations of data in cells which are the intersection of multiple dimensions.

Metadata
Data about data - describes the characteristics of the data.

MIB
Management Information Base - describes the management information conveyed over SNMP. MIB objects and their values are what is transmitted over SNMP. Written in SMI (Structured Management Information) syntax.

MLS
Multi-Level Secure

MOM
Message-Oriented Middleware

MPP
Massively Parallel Processing machines - loosely coupled hardware architecture where the node are plugged into a specialized chassis containing integrated low-latency, high-bandwidth interconnect hardware (high speed switch). Each node has it's own CPU, memory, bus, and disk and can perform a task without contention or interruption by a task being performed on another node (each node runs its own O/S kernel and Oracle database instance - must use Oracle Parallel Server for MPP environment). MPPs usually have uniprocessor nodes unlike a Clustered system where nodes are SMPs. Messages are sent across an interconnect for communications between nodes and the interconnect is more sophisticated than a Clustered machine and the interconnect's bandwidth increases as the number of nodes increase. Has the ability (unlike SMP or SMP clusters) to achieve application scalability by adding processor nodes. Best used for operation partitioning (parallelism), not application/user partitioning or transaction partitioning (TP monitors). Most suitable applications for MPP are read-only type applications (don't have to read other node's caches because the data it reads will either reside in it's own cache or on disk) and applications that are highly partitionable. Usually choose MPP over SMP if have a complex analytical or large scale DSS application where the primary aim is strategic advantage, growth is rapid and unpredictable, and raw-data size >= 500 GB.

Modem
A piece of equipment that connects a computer to a data transmission line (typically a telephone line of some sort). Most people use modems that transfer data at speeds ranging from 1200 bits per second(bps) to 19.2 Kbps. There are also modems providing higher speeds and supporting other media. These are used for special purposes-for example, to connect a large local network to its network provider over a leased line.

Modularity
Streamlines code organization into easily defined functional areas.

NCF
Network Computing Framework - is an open, standards-based network computing model for creating expandable e-business solutions. (IBM's)

Netscape ONE
Netscape's open environment for network-centric application development and deployment - based on CORBA/IIOP.

NFS
Network File System - the most widely used distributed file system. It is standard on most UNIX machines and does not require a license to use. NFS clients and servers are also available for Windows and Windows NT machines.

NUMA
Non-Uniform Memory Access

Object Reuse
Re-use solutions that have already been developed - don't recreate same functionality. Object groups in Oracle Forms encapsulate a number of objects and triggers into a reusable component - allows error-free use b/c won't forget some objects that are needed for the application. Form's template forms ensures similar look and feel of application by attaches libraries, object groups, property classes, and color palettes into 1 template form.

Object Subclassing
Provided with Developer/2000 - replaces referencing objects. Any attribute of a referenced object can be changed. Connection between source and referenced objects are live if both are in memory and if changed source property hasn't already been overridden on referenced object. Can create objects as subclass of other objects which are also subclassed from another object (subclassing hierarchy).

OCX
OLE Custom Extensions (Control)

ODBC
Open Database Connectivity

ODMA
Open Document Management API

OEM
Original Equipment Manufacturer

OLE
Object Linking and Embedding (Microsoft) - two different interface languages it supports are ODL (describes metadata) and MIDL (describes RPC linkages).

OMG
Object Management Group - industry-standards consortium that is defining key interoperability standards for distributed-object computing.

Open
Freedom of choice in hardware/software platform.

OpenDOC
A desktop object component first proposed by Apple, IBM, Lotus, and others. It's a true cross-platform object-component model. The OMG has endorsed it as its client-side distributed-object model standard, but will also support a CORBA to OLE/COM bridge.

Operating System
The system software that manages a computer's resources, performing basic tasks such as allocating memory and allowing computer components to communicate.

ORB
Object Request Broker - an object bus which enables objects to communicate with other objects located locally or remotely. Companies like IONA, Expersoft, and Visigenic have commercial ones.

OSI
Open Systems Interconnection

OTM
Object Transaction Monitors

OTS
Object Transaction Service - a CORBA solution for distributed object transactions.

Parallel Systems
Needed to handle large problems by having enormous processing power, storage, and I/O. Used if need to scale to handle rapid growth - types are SMP, Clustered, and MPP.

PC
Personal Computer

PCMCIA
Personal Computer Memory Card International Association

Polymorphism
Create generic code that can be used in a variety of different situations and it's action depends upon the current circumstance. Differing object classes can implement the same function in a manner that is appropriate for its class. A GIS example is an Area function that is defined both for rectangle and circle objects or a DisplayError function for both number and varchar2 classes. Oracle Forms uses overloading to accomplish this.

Preemptive Multitasking
The means for deciding which process gets the system's attention at any given moment, at which time the system can choose to take control form one process and give it to another. UNIX, Windows 95, OS/2, and Windows NT use preemptive multitasking. However DOS, Windows 3.1, and System 7 do not support this sharing attitude. Therefore, when one process gains control it will continue to maintain control until its task is completed or it chooses to relinquish control. Thus, when a program gets out of control and crashes, it is impossible to regain control of your computer without rebooting it. With preemptive multitasking, it is possible simply to kill off the offending process and move on.

Programmable
Allow complex business rules and functions to be stored in the database.

Protocol
A protocol is just a definition of how computers will act when talking to each other. Protocol definitions range form how bits are placed on a wire to the format of an electronic mail message. Standard protocols allow computers from different manufacturers to communicate; the computers can use completely different software, providing that the programs running on both ends agree on what the data means

RAD
Rapid Application Development

RAID

Raw Devices
Unmounted UNIX disk section that Oracle can use for data files and redo logs. When I/O is performed against it it bypasses processing overhead of the file buffering in UNIX's file system.

RISC
Reduced Instruction Set Computer

RMI
Remote Method Invocation - a way for JAVA programs to call methods on remote JAVA programs - a JAVA to JAVA only interaface. If you need JAVA to have an IDL interafce use Sun's IDLGEN compiler which creates JAVA classes based on a given IDL.

Router
A system that transfers data between two networks that use the same protocols. The networks may differ in physical characteristics (e.g., a router may transfer data between an Ethernet and a leased telephone line).

RSA
Secret key ciphers for data encryption.

Scalability
Fully leverage the CPUs available on the chosen hardware platform - allowing more data and more users to access the database. The engine's ability to support expanding user community and more complex application processing requirements with linear performance - get improved performance on higher-end multiprocessor machines.

SGML
Standard Generalized Markup Language - a language that is used to define markup languages. For example, the HTML and 2.0 and 3.0 specifications define HTML in a SGML grammar.

Shared-Disk/Shared-Nothing
2 main parallel architectures used in MMPs and Clustered systems (loosely coupled hardware architectures). In a shared-disk approach (Digital VAX clusters - Rdb, Oracle, Ingres, DB2 for MVS v.4) each processing node can read, buffer in memory, and update the same data - on any disk. A DLM (Distributed Lock Manager) maintains consistency across the multiple nodes. Has high overhead requirements. Pinging occurs when users update the same data so blocks are written to disk by one node and read up by another. In a shared-nothing approach (Teradata DSS, Tandem OLTP, Sybase Navigation Server, IBM DB2 for AIX, Informix OnLine, AT&T, DEC, DG, HP, IBM, Pyramid, Sun, Sequent, most MPP machines) each processing node can only access the disk attached to it - improves performance because minimizes inter-node data movement. The database is partitioned and nodes have exclusive access to those partitions. Low overhead b/c no need for a DLM, but more complex for DBA to manage (need monitoring and data reorganization tools). Better performance if user can run on a node owning all the data. A hybrid approach (IBM SP/2) has disks attached to particular nodes, but any node can still access any disk.

SI
Systems Integrator

Signed Objects
Signed objects allow trusted distribution and execution of software applications and "applets" as part of extranet networks. Adoption of this standard ensures that software downloaded as part of an application will be guaranteed to be uninterceptable and secure during transfer.

SMEs
Small and Midsize Enterprises

SMP
Symmetric Multi-Processing machines - a tightly coupled hardware configuration (like uni-processor) like HP Emerald or Sun SPARC w/ more than 1 CPU. It is a parallel system that has a few dozen processors and each one shares all the hardware resources including memory, disk, and system bus (shared-everything). A single copy of the OS controls the environment (the same bus and memory are also shared so it produces a common point of contention between he CPU's when under load). Usually choose SMP over MPP if have mission-critical OLTP or medium scale decision support system where growth is steady and slow, total database size <= 300 gb, oltp users <= 2,000, and # oltp transactions/minute b/w 2,000 and 8,000.

SNMP
Simple Network Management Protocol - the standard way of communicating management information. Simply defines how the information is conveyed - how communications are initiated, structured, and handled. It enables administrators to monitor Oracle server and SQL*Net components through SNMP-based management consoles.

SOM/DSOM
System Object Model and Distributed System Object Model - IBM-specific object frameworks.

SOW
Statement of Work

Striping
Practice of dividing a large table's data into small portions and storing these portions in separate data files on separate disks. It distributes disk I/O thereby improving performance. However, it does nothing to control the random distribution of data. Form of server-level data partitioning unlike doing a UNION of smaller tables which is a form of application-level partitioning.

TQM
Total Quality Management

TP
Transaction Processing

TP Monitors (XA-Compliant)
A layer of software that provides an interface between application programs and the database manager. It controls database accesses in terms of which and how many transactions can be working in the database at any one time - you can also prioritize transactions. It acts as a traffic cop performing such tasks as directing transaction requests to available system resources; ensuring an even distribution of the work load; guaranteeing transaction integrity and rolling back transactions in the event of system failure; and managing expensive system resources. They are being used as the middleware that interconnects various open systems, legacy systems, and databases from multiple vendors on enterprise networks that frequently run multiple network protocols like TCP/IP and IBM's SNA. Like multithreaded server - clients talk to TP monitor which then distributes connections to server. Three tier DTP model - Application Program (AP), Transaction Manager (TM), and Resource Manager (RM) - the RDBMS. Examples - IBM/MVS CICS, Tuxedo (BEA Systems). Use a TP monitor if you need heterogeneous two-phase commit - the ability to synchronize updates across two or more databases from different vendors. But, they are more than just two-phase commit. They also provide two other distinct types of services essential to building scalable distributed applications. First, they offer robust and efficient communication services between clients and servers and between one server and another. This enables applications to run efficiently over low-speed, high-latency WANs, including the Internet. Second, they offer server-based execution environments that handle the low-level multitasking, connection and state management plumbing that enables user-written services to efficiently handle thousands of client requests.

VAD
Value-Added Distributor - primarily two-tier distributors meaning that they purchase product directly from a manufacturer, resell that product or service to resellers, who in turn resell to end users. "Two-tier" refers to the number of parties between the manufacturer and the end-user.

VAR
Value-Added Reseller

vCards
vCards provide a structured format for exchange of personal contact information. A vCard is your electronic business card and is used to share your contact information with other users, applications and websites. The key benefits of vCards are:
VLM
Very Large Memory option - a.k.a. 64-bit option. Used with new hardware needed for very fast databases.

VOD
Video on Demand

VPA
Volume Purchasing Agreement

VPN
Virtual Private Network

VxD
Virtual Device Driver - a special kind of device driver that virtualizes a single system resource among multiple system clients.

X/Open
Distributed Transaction Processing (DTP) model which includes an application program (like Oracle's WebServer 3.0 cartridge), a resource manager (like Oracle's database), and a transaction manager (like Oracle's Web Request Broker). It's XA specification is for communication between the resource manager and the transaction manager. It's TX specification is for communication between the application program and the transaction manager.

XBSA
A standard set of APIs set by X/Open committee which allows data management applications to interface directly to storage management applications.



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