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Glossary of Terms

Justice Information Sharing
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Glossary of Terms

The Glossary identifies and defines terms commonly used in the information technology and justice communities.

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800 Megahertz
800 MHz refers to public safety radio systems using channels located in or near the 800 MHz band. Approximately 300 channels located in the 800 MHz spectrum band have been assigned for use by state and local public safety entities. The disadvantage is that this higher frequency has less range and so a greater infrastructure is needed to cover the same range as lower frequencies. Problems with incompatibility frequently occur between different 800 MHz trunked systems built by different vendors.


AFIS (Automated Fingerprint Identification System)
AFIS is a database of digitized offender fingerprint files. A user can enter a fingerprint and a computer will generate a list of possible matches within minutes. The matches are then examined and verified by a fingerprint expert.

Architecture refers to the design of a system. It may refer to either hardware or software or a combination of both.

AVL (Automatic Vehicle Locator)
AVL uses Global Positioning System technology to locate the position of patrol cars on a digital map. This information assists the dispatcher in knowing which calls should be assigned to which officers.


BIOS (Basic Input / Output System)
BIOS controls the startup of the machines or computers and other functions such as the keyboard, display, and disk drive. The BIOS is stored on read-only memory and is not erased when the computer is turned off. The BIOS on newer machines is stored on flash read-only memory, allowing it to be erased and rewritten to update the BIOS.


CAD (Computer Aided Dispatch)
CAD is a computer system that assists 911 operators and dispatch personnel in handling and prioritizing calls. Enhanced 911 will send the location of the call to the CAD system that will automatically display the address of the 911 caller on a screen in front of the operator. Complaint information is then entered into the computer and is easily retrievable. The system may be linked to MDTs in patrol cars allowing dispatchers and officers to communicate without using voice. The system may also be interfaced with NCIC, AVL, or a number of other programs.

CDPD (Cellular Digit Packet Data)
CDPD is a data transmission technology that uses unused cellular phone channels to transmit data in packets.

Client / Server Architecture
Client / server architecture is a network model that a computer or process server uses to provide services to the workstations (clients) connected to that computer (server). This architecture allows the client to share resources such as files, printers, and processing power with other clients.

Hardware and software capable of satisfying a particular requirement, such as manipulation of four-digit dates, is deemed ''compliant.''

Computer Crime Mapping
Computer crime mapping allows a department to display calls for service on a computerized pin map that aids in crime analysis efforts.

Conversion is the translation of valid values into another format on a permanent basis; for example, translating two digit years to four-digit year values.


Data Dictionary
A data dictionary is a file that defines the basic organization of a database. It will contain a list of all files in the database, the number of records in each file, and the names and types of each field.

Data Standards
Data standards are agreed upon terms for defining and sharing data.


Encryption is a process that translates plain text into a code (ciphertext) as a mechanism for protecting its confidentiality, integrity, and sometimes its authenticity. The reader of an encrypted file must use an encryption algorithm and one or more encryption keys to decrypt the file.


Firewalls are systems designed to prevent unauthorized access to or from a private network. They are often used to prevent Internet users from accessing private networks connected to the Internet.

Functional Specifications
Functional specifications are formal descriptions of a software system used as a blueprint for implementation. Specifications should state the purposes of the program, provide implementation details, and describe the specific functions of the software from the user's perspective.


GPS (Global Positioning System)
GPS is a satellite navigation system operated by the U.S. Department of Defense. It provides coded satellite signals that can be processed by a GPS receiver enabling the receiver to compute position, velocity and time.

GUI (Graphical User Interface, often pronounced ''gooey'')
GUI is a program interface that uses a computer's graphic systems to make a program more user-friendly. A GUI may include standard formats for representing text and graphics making it easier to share data between programs running on the same GUI.


Hardware are objects used to store and run software, such as a computer, monitor, keyboard, disk, and printer.


IAFIS (Integrated Automated Fingerprint Identification System)
IAFIS is a new (July 1999) national online fingerprint and criminal history database run by the FBI. Justice agencies that submit urgent electronic requests for identification will receive a response within two hours.

III (Interstate Identification Index)
Designed and run by the FBI, III is part of IAFIS and contains criminal history records for almost 30 million offenders and can be queried using a name, birth date, and other information.

Integration is the application of technology to improve information management and information sharing between justice enterprise agencies at all levels of government.

Interface is a program or device that connects programs and/or devices.

Internet is a decentralized global network connecting millions of computers.

Intranet is a secure private network that uses TCP/IP protocols.


An object-oriented programming language that is platform independent (the same Java program runs on all hardware platforms without modification). Java is widely used on the Web for both client and server processing. Modeled after C++, Java added programming enhancements such as ''garbage collection,'' which automatically frees unused memory. It was also designed to run in small amounts of memory.

Java programs can be called from Web pages or run stand alone. When launched from a Web page, the program is called a Java ''applet.'' When a non Web-based Java program is run on a user's machine, it is a Java ''application.'' When running in a Web server, it is a Java ''servlet.''

Java is a full-blown programming language, whereas JavaScript is a scripting language that is much more limited in scope. JavaScript source code is not compiled into bytecode. It is embedded within an HTML page and is primarily used to manipulate elements on the page itself. For example, JavaScript is widely used to provide drop-down menus and other interactive events on the page.


LAN (Local Area Network)
LAN is a computer network that connects workstations and personal computers and allows them to access data and devices anywhere on the LAN. A LAN is usually contained within one building.

Laptop is a computer that has capabilities beyond that of the Mobile Data Computer. It may contain report writing and accident reconstruction programs.

LAWN (Local Area Wireless Network)
LAWN is a LAN that uses high frequency radio waves rather than wires to communicate between nodes.

Legacy System
Legacy systems are older software and hardware systems still in use and generally proprietary.

Live Scan
Live scan is a machine that replaces ink and roll fingerprints. Fingers are rolled across a platen, scanned into a computer, and converted to a digital form of storage. Fingerprint cards are then printed out on a laser printer. The machine will immediately reject low quality prints.


MDC (Mobile Data Computer)
MDC is a microcomputer used by public safety agencies to access databases for information on persons and property. The MDC uses wireless communication and allows an officer to exchange information with the dispatcher and other officers without using voice channels.

Metadata is data that describes data.


NCIC or NCIC 2000 (National Crime Information Center)
NCIC is a computer system maintained by the FBI that can be queried by local agencies via state computer systems known as ''control terminal agencies.'' NCIC contains 17 files with over 10 million records, plus 24 million criminal history records contained within the Interstate Identification Index (one of the 17 files). Files include the III, the Missing Persons File, the Unidentified Persons File, the U.S. Secret Service Protective File, and the Violent Gang/Terrorist File.

A network is created when two or more computers are joined by some type of transmission media allowing them to communicate directly, or to share storage devices and peripherals. Transmission media can include cable lines, telephone lines or satellite systems.

NIBRS (National Incident Based Reporting System)
NIBRS is an incident based reporting system, run by the FBI, through which data is collected on each single crime occurrence. NIBRS data is designed to be generated as a by-product of local, state, and federal automated records systems. NIBRS collects data on each single incident and arrest within 22 offense categories made up of 46 specific crimes called Group A offenses. Specific facts are collected for each of the offenses coming to the attention of public safety agencies. In addition to Group A offenses, there are 11 group B offense categories that only report arrest data. NIBRS is expected to eventually replace UCR.

Nlets - The International Justice and Public Safety Network
Nlets is a high-speed communications network and message switching that connects almost every public safety agency in the country. It allows local agencies to make inquiries into state databases to access criminal history records, vehicle registration records, driver's license files, etc. Nlets also interfaces with NCIC and other national files and allows states to exchange information with each other. The mission of Nlets - The International Justice and Public Safety Network is to provide, within a secure environment, an international criminal justice telecommunication capability that will benefit, to the highest degree, the safety, security, and preservation of human life and the protection of property. Nlets will assist those national and international governmental agencies and other organizations with similar missions who enforce or aid in enforcing local, state, federal, or international laws or ordinances.

A node can be a computer or some other device such as a printer. Every node has a unique network address.


A self-contained module of data and its associated processing. Objects are the software building blocks of object technology.

Object Oriented Programming
Object oriented programming combines data structures and functions (computer directions) to create ''objects,'' making it easier to maintain and modify software.

Open Architecture
Open architecture systems are designed to allow system components to be easily connected to devices and programs made by other manufacturers.

Open Source
Refers to software that is created by a development community rather than a single vendor. Typically programmed by volunteers from many organizations, the source code of open source software is free and available to anyone who would like to use it or modify it for their own purposes. This allows an organization to add a feature itself rather than hope that the vendor of a proprietary product will implement its suggestion in a subsequent release.

Open source developers claim that a broad group of programmers produces a more useful and more bug-free product. The primary reason is that more people are constantly reviewing the code. This ''peer review,'' where another programmer examines the code of the original programmer, is a natural byproduct of open source. Peer review is an important safeguard against poorly written code.

Operating System
Operating system is the basic program used by a computer to run other programs. An operating system recognizes input from the keyboard, sends output to the display screen, and keeps track of files and directories on the disk and controlling peripheral devices such as disk drives and printers. It provides a platform for other software applications.


Platform is the underlying hardware or software for a system. The term is often used as a synonym for operating system.

The term ''proprietary'' generally refers to a system whose manufacturer will not divulge specifications that would allow other companies to duplicate the product. It is also known as a closed architecture.


To interrogate a collection of data, such as records in a database. The term may also be used to search a single file or collection of files, such as HTML files on the Web. However, in addition to obtaining lists of records that match the search criteria, queries to a database allow for counting of items and summing amounts. A query on the Web yields only a list of matching pages and is more often called a ''search.''


Regression Test
A regression test is performed before production to identify and prevent errors and verify that unchanged software will continue to function as designed.

Relational Database Management System
A relational database management system is a type of database management system that stores data in related tables. New types of data can more easily be added, and the user can view the data in multiple ways.

RFID (Radio Frequency Identification)
A wireless data collection technology that uses electronic tags for storing data. Like bar codes, they are used to identify items. Unlike bar codes, which must be brought close to the scanner for reading, RFID tags are read when they are within the proximity of a transmitted radio signal. Because RFID tags hold more data than bar codes, which generally contain only a product ID, the RFID tag can be used for tracking individual items.

RMS (Records Management System)
An RMS stores computerized records of crime incident reports and other data. It may automatically compile information for UCR or NIBRS reporting. Can perform greater functions when integrated with other systems such as CAD and GPS.


''Scalable'' is a term that describes how well a system can be adapted and expanded to meet increased demands.

Scope Creep
Scope creep is the slow and continuous expansion of the scope or a project, such as data type or routine, resulting in a broad, unfocused, and unmanageable scope and usually leads to cost-overruns, missed deadlines, and loss of original goals.

A server is the program in the client/server architecture that answers client's requests. The term ''server'' is also used to designate the computer that makes resources available to the workstations (clients) on the network.

Software is a set of computer instructions or data stored in an electronic format.

Spectrum refers to the array of channels, like the channels on a television, available for communications transmissions. Commonly referred to as a spectrum, these channels are a finite natural resource; they cannot be created, purchased, or discovered.

SQL (Structured Query Language)
SQL is a language used specifically by a relational database to query, modify, and manage information. SQL commands can be used to interactively work with a database or can be embedded within a programming language to interface to a database. Programming extensions to SQL have turned it into a full-blown database programming language, and all major database management systems (DBMSs) support the language.

Systems Software
Systems software consists the operating system and all utilities that enable the computer to function.


TCP/IP (Transmission Control Protocol/Internet Protocol)
TCP/IP is standard transmission protocol used to connect hosts on the Internet.


UCR (Uniform Crime Reports)
UCR is a city, county, and state public safety program operated by the FBI that provides a nationwide view of crime based on the submission of statistics by public safety agencies throughout the country. The following offenses are recorded: murder and nonnegligent manslaughter; forcible rape; robbery; aggravated assault; burglary; larceny theft; motor vehicle theft; arson; and hate crimes.


A validation is the evaluation of a system during development or at the time of completion to determine if it satisfies all the requirements.


WAN (Wide Area Network)
A WAN consists of two or more LANs connected via telephone lines or radio waves.

Web Browser
Web browser is a software application used to locate and display web pages. May be able to display graphics, sound, and video in addition to text.

World Wide Web (WWW)
WWW is a system of Internet servers that support HTML formatted documents. t servers that support HTML formatted documents.