glossary of security system terms and definitions

Security systems combine devices and practices to protect facilities and their occupants from threats such as intruders, theft, vandalism, and natural disasters. By integrating these systems with other building functions, businesses can create a cohesive and highly efficient approach to safety and emergency response. To help expand industry knowledge, we partnered with leading manufacturers to compile this comprehensive glossary of door access control and security system terms.

A

• Access Card
  Access control identification device assigned to an individual to give that individual access rights to an access control system. Typically, it is the size of a credit card. Each card has a unique identification code. That identification code is used by a controller to determine through which doors and at what times cardholders may be granted access to a secure area. See Key Tag.
• Access Code
  Numeric or alphanumeric data which, when entered correctly, authorizes entry into a secure area.
• Access Control
  General term describing the control, management, and monitoring of the entrance and exit of people through secure areas.
• Access Control Card
  Identification card with encoded information that, when presented to a card reader, identifies the cardholder to an access control system, allowing that system to determine the cardholder's entrance and exit rights.
• Access Control Network
  See Access Control System.
• Access Control System
  Interconnected set of controllers, managing the entrance and exit of people through secure areas.
• Access Group
  Superset of information including Timezones and secured Doors that is applied to cardholders. This information defines at what time-of-day and through which doors cardholders are granted access.
• Access Level
  See Authorization Level.
• Access Mode
  Condition in which all access parameters have been met, allowing an access control system to grant access.
• Access Point
  Point of entry into a secure area. This point is typically managed by a controller using some combination of a card reader, an electric door lock, gate, turnstile, or similar device.
• Access Parameters
  Programmed information that define the conditions that must be met to grant access. Such parameters may include access codes, access groups, authorization levels, or Timezones.
• Access Request
  Act of presenting the information necessary to verify a person's identity.
• Acquired Data
  Data collected from an event that is used to make a decision, or is saved for future analysis.
• Active Card
  Type of access control card that is dependent upon a card reader to provide the power necessary to allow the card to transmit its data.
• Actuator
  Manually operated or automatically controlled switch or sensor which initiates a signal that can be processed by an access control system.
• Alarm Annunciation
  Act of announcing that an alarm event has occurred. Annunciation can be done by an audible alarm, warning lamp or LED, or a pop-up window or message (in the case of alarm monitoring via computer software).
• Alarm Disable
  Ability to physically or electronically make an alarm input unaccessible to an access control system.
• Alarm Enable
  Ability to physically or electronically make an alarm input accessible to an access control system.
• Alarm Mask
  Ability to selectively suppress the annunciation of certain alarm conditions, but allowing all other alarm conditions to properly report.
• Alarm Relay Output
  Relay on the controller that changes its state upon command by the controller. Often the alarm relay output activates an audible alarm used to annunciate a door alarm.
• Alphanumeric
  Text string made up of alphabetic and numeric characters.
• American Wire Gauge (AWG)
  Standard for designating wire dimensions and specifications.
• Annunciator
  Device (such as a light or horn) that indicates an event has occurred.
• ANSI
  Acronym for American National Standards Institute.
• Anti Passback (APB)
  Method for providing one-card, one-way access into and then out of a secure area. It prevents someone from using a card to enter a secure area and then passing that card back to someone else to enter that same area.
• APB
  See Anti Passback.
• Attended ID Station
  Station where a security individual verifies the identity of someone seeking to enter a secure area.
• Audit Trail
  Sequential record that accounts for all the activities of an access control system. This record allows for the analysis of events over a given time period.
• Authorization Level
  Security rating that must be met before access to a secure area is granted.
• Authorized Person
  Person who has been cleared to enter a secure area.
• Automatic Time Switch
  Timer that turns devices on or off at preset times.
• Auxiliary Code
  Secondary code (often used on a temporary basis) that can be used for granting access or allowing access control system operation without revealing a primary code. See Primary Code.
• Auxiliary RTE
  Second input source that informs the controller that someone has requested to exit from a secure area. See Request to Exit.
• AWG
  See American Wire Gauge.

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B

• Badge Reader
  Reader used to read and interpret data encoded in an identification badge. See Card Reader.
• Badging Software
  Security software that is capable of creating Photo Identification badges.
• Bar Code
  Method of encoding information using lines and blank spaces of varying size and thickness to represent alphanumeric characters.
• Bar Code Card
  Access control card with identification information encoded in Bar Code format.
• Bar Code Reader
  Reader capable of reading and interpreting cards using bar codes to encode data.
• Barium Ferrite Card
  Access control card with identification information encoded in the card via magnetic material embedded in the card.
• Barium Ferrite Reader
  Reader capable of reading and interpreting cards using barium ferrite to encode data.
• Batch Programming
  Method for processing data or performing tasks in which a number of commands are collected and then processed by a controller all at one time.
• Battery Backup
  Secondary energy source used to power devices in the event the primary energy source fails. Battery Backup typically provides power for a short period of time, allowing for immediate action, system protection, and system shutdown before the battery reaches a drained state.
• Baud
  Unit of data signal transmission speed, typically expressed in bits per second.
• Bell Transformer
  Small transformer used to reduce power line voltage to the level required by low power devices (i.e. card readers).
• Binary Coded Decimal (BCD)
  Decimal numbers 0 through 9 expressed in a 4-bit binary format.
• Biometrics
  General term for the verification of individuals using unique biological characteristics (i.e. fingerprints, hand geometry, voice analysis, the retinal pattern in the eye).
• Biometric Access Control
  Access control where the identification process is made through biometric parameters. See Access Control, Biometrics.
• Bit
  Abbreviation for binary digit in the binary number system. A bit will have the value of either 0 or 1.
• Break Before Make
  Type of switch in which one set of contacts open before another set of contacts closes.
• Bus
  [a] In power systems, a solid metal or uninsulated wire connector from which a universal type of power or ground connection is made. [b] In computer or data transmission systems, the principal channel through which all major sections communicate.
• Byte
  Group of eight binary data bits.

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C

• Card
  Identification device assigned to an individual that identifies that individual. Typically, it is the size of a credit card. See Access Card, Key Tag.
• Card Access
  Type of access control system using encoded cards and card readers to identify cardholders and determine if access may be granted. See Cardholder.
• Card Encoder
  Device used to encode data onto an access card.
• Card Reader
  Device that retrieves information stored on an access card and transmits that information to a controller.
• Cardholder
  Individual who has been assigned an access control card or tag.
• Checksum
  Additional set of information transferred with a computer program or a data stream that is used to verify the accuracy of the data just transferred.
• Chip-In-Card
  See Smart Card.
• Circle of Protection
  Security plan in which the items to be protected are surrounded by two or more protective zones of increasing size.
• Circuit Breaker
  Switch on an incoming power circuit that opens if abnormal circuit conditions arise (such as an overload or short circuit).
• COM Port
  Hardware device that allows a computer to communicate with external devices.
• Conductor
  Material that readily allows electricity to flow through it. Most metals are good conductors.
• Contact
  Magnetically or electrically controlled connection point that opens or closes to interrupt or allow the flow of current.
• Contact Rating
  Load rating of a switch, listed by maximum voltage and/or current accepted by the switch.
• Control Center
  Central location in a secure area where access and alarm sub-systems are supervised and security personnel are located.
• Control Point
  Exit or entry point such as a door, turnstile, or gate, where access is controlled.
• Controller
  Microprocessor based circuit board that manages access to a secure area. The controller receives information that it uses to determine through which doors and at what times cardholders are granted access.
• CSA
  Label signifying that the product has met requirements set by CSA International.
• Cypher Lock
  Digital push-button combination lock.

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D

• Dedicated I/O Point
  Input or output that is dedicated to a specific function.
• Dedicated Telephone Line
  Telephone line directly connecting two points. Also Known As - Lease Line.
• Degausser
  Device that creates a strong magnetic field that erases data from magnetically encoded media such as magnetic stripe cards.
• Degraded Mode
  Mode of controller operation that provides a minimal authorization level in the event of controller failure.
• Delayed Egress
  Prevents a door from being opened from the egress side, usually for a period of 15 seconds.
• Distributed Access Control
  Access control systems in which all control decisions are made at the local controllers, independent from a host computer.
• Door
  Generic term for a securable entry way. In many access control applications a "door" may actually be a gate, turnstile, elevator door, or similar device.
• Door Forced Alarm
  Alarm generated when a door is forced open, opening the door switch contact.
• Door Held Open Alarm
  Alarm generated when a door is held open beyond the designated period of time.
• Door Held Open Time
  Amount of time from when a door is opened before an alarm is generated for the door being opened too long.
• Door Switch
  Switch that reflects the state of the door: if the door is open, the switch is open — if the door is closed, the switch is closed.
• Download
  Sending information from a host computer to a peripheral device in an access control system.
• DPDT (Double Pole, Double Throw)
  Switch routing two separate circuits, connecting each of two inputs to one of two outputs.
• DPST (Double Pole, Single Throw)
  Switch turning two circuits on or off.
• Duress
  Forcing a person to provide access to a secure area against that person's wishes.
• Duress Alarm
  Device that generates a silent alarm signal in the event a person is experiencing Duress.
• Duress Code
  Alphanumeric code which alerts the system to a Duress condition.
• Duty Cycle
  Ratio of system ON time to system OFF time.

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E

• Earth Ground
  Electrical connection point that brings all electrically neutral lines to the earth's surface potential. See Ground.
• Egress
  A place or means of going out (Exit).
• Electric Door Lock
  Remotely operated electric locking device. See Electric Strike, Electromagnetic Lock.
• Electric Strike
  Electric door lock that requires power to be applied to unlock a door.
• Electromagnetic
  General term referring to the electric and magnetic fields associated with the movement of electrons through conductors.
• Electromagnetic Interference (EMI)
  Excess electromagnetic energy radiated by an electrical device that may affect the operation of other electrical devices.
• Electromagnetic Lock
  Electric door lock that uses an electromagnet to hold a door closed. See Magnetic Lock.
• Embossed Card
  Access control card that uses a raised pattern as a means of encoding data.
• EMI
  See Electromagnetic Interference.
• Encoding
  Process of writing data to a card.
• Entrance Delay
  See Door Held Open Time.
• EPROM
  Acronym for Erasable Programmable Read Only Memory.
• Event
  Occurrence at a controller (such as unlocking a door) that generates a message stored by the controller.
• Exit Alarm
  Device that indicates (either audibly or silently) that a secure door has been forced opened.
• Exit Lock
  Push-bar door lock that spans the width of the door, used for emergency exit.
• Exit Reader
  Reader used to control exiting from a secure area.
• Exit Switch
  Switch that is used to initiate a Request to Exit.
• Explosion-proof
  See Intrinsic Safety.

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F

• Facility Code
  Coded data in access control cards that identifies the location of the access control system.
• Fail-Safe Door
  Fail-safe door is one that if the power should fail at that door, the door will automatically unlock allowing exit and entrance. [Fail-Safe = People Safe]
• Fail-Safe Lockset
  Lockset that is normally locked when the power is ON, and automatically unlocks when the power fails.
• Fail-Secure Door
  Fail-secure door is one that if the power should fail, the door will automatically lock and not allow entrance, but will continue to allow exit. [Fail-Secure = Property Secure]
• Fail-Secure Lockset
  Lockset that is normally unlocked when the power is ON, and automatically locks when the power fails.
• False Alarm
  Alarm signal generated without an existing alarm condition.
• Fingerprint Pattern Area
  Identifying characteristics of a fingerprint, consisting of the arches, loops, and whorls.
• Fingerprint Reader
  Biometric reader that identifies a person based on their fingerprint pattern.

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G

• Gate
  Generally considered a perimeter (outside) door.
• General Protection Fault
  Operating system fault that occurs whenever a program executes a command considered dangerous to the OS.
• Global Unlock
  Normally-open input that, when closed, generates a signal that unlocks all doors in the access control system.
• Ground
  [a] Electrical connection with a ground potential point. [b] Electrical connection to a circuit's zero voltage reference point. See Earth Ground.

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H

• Hand Geometry
  Biometric access control technology that verifies a person's identity by using the variations in hand size, finger length, and thickness.
• Historical Log
  Chronological record of events.
• Host Computer
  Central controlling computer from which access control software applications are run.

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I

• Identification
  Act of recognizing one person as being unique from all other people.
• Identification Card
  Card that stores the information necessary to verify the identity of the cardholder.
• Infrared Light
  Light with a wavelength that is too low to be seen by the human eye.
• Infrared Motion Sensor
  Sensing unit that detects motion based on the disruption of infrared light waves.
• Ingress
  The act of entering (Entrance). The power or liberty of entrance or access.
• Input
  Electronic sensor on a controller that detects a change of state in a device outside the controller. See Normally-Closed, Normally-Open.
• Insertion Card
  Card that must be inserted into a reader for the reader to retrieve the information stored on the card.
• Intelligent Device
  Type of microprocessor-based input, output, or sensor device that has free-standing logic capability.
• Intrinsic Safety
  A protection technique for safe operation of electrical equipment in hazardous areas by limiting the energy, electrical and thermal, available for ignition.

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J

• Jumper
  Movable device that allows connections to be made between points on a circuit board.

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K

• Key Tag
  Access control identification device assigned to an individual to give that individual access rights. See Card.
• Keyless Access Control
  Access control system that controls access using something other than a key and a lock.
• Keypad
  Alphanumeric grid which allows a user to enter an identification code.
• Keyswitch
  Lockable switch operated by a key.

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L

• Latching Relay
  Relay that when set locks into place until reset either manually or by a signal.
• LCD
  Abbreviation for Liquid Crystal Display.
• LED
  Abbreviation for Light Emitting Diode.
• Lease Line
  See Dedicated Telephone Line.
• Line Drop
  Drop in voltage along a power line caused by the resistance, reactance, and/or leakage in the line's wires.
• Lock Relay Output
  Relay on the controller that changes its state upon command by the controller, locking or unlocking a secure door.
• Logging
  Creating and storing a permanent record of events that can be reviewed, printed, and analyzed.

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M

• Maglock
  Abbreviation for electricmagnetic door lock that uses an electromagnet to hold a door closed. See Magnetic Lock.
• Magnetic Contact
  Device that sends a signal when the magnetic field between two monitored points is broken.
• Magnetic Lock
  Door lock made up of an electromagnet and a strike plate.
• Magnetic Stripe Card
  Access control card with a strip of recordable magnetic material, on which data is encoded.
• Magnetic Stripe Reader
  Reader capable of reading and interpreting cards using magnetic stripes.
• Master Code Card
  Access control card that grants access and exit at every card reader on the system.
• Memory
  Section of a host computer or a controller in which data and instructions are stored.
• Modem
  Communication device that converts computer serial data to an analog format.

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N

• Network
  [a] Series of controllers, all connected via a communications cable. [b] Group of computers, all connected via a communications cable.
• Normally-Closed
  State of an input device that continually keeps a circuit closed or complete until forced by an action.
• Normally-Open
  State of an input device that continually keeps a circuit open or incomplete until forced by an action.

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O

• Online Help
  Reference program within most software programs that provides basic descriptions and instructions.
• Output Relay
  Device that changes its state upon receiving a signal from a controller.

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P

• Panic Bar
  Quick release door lock allowing the door to be quickly opened in the case of an emergency situation. Also known as Crash Bar.
• Photo Badging
  See Badging Software.
• Personal Identification Number (PIN)
  Unique numerical code used to identify an individual.
• Piggybacking
  [a] More than one individual entering a secure area using one access card. [b] Following an authorized person into a secure area. See Anti Passback.
• PIN
  See Personal Identification Number.
• Primary Code
  Main identification information provided by an individual to gain access. See Auxiliary Code.
• Programmable Card
  Card in which data may be encoded.
• Programmable Card Reader
  Card reader in which instructions for granting or denying access may be programmed.
• Proximity
  Method of reading a card or key tag without requiring any physical contact between the card/tag and the reading device.
• Proximity Card
  Card using proximity technology to store and transmit encoded data.
• Proximity Reader
  Reader capable of reading and interpreting cards using radio frequency identification.
• Push-Button Lock
  Lock that opens when a set of push-buttons are pressed in sequence or in unison.

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Q

• No current definitions.

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R

• Radio Frequency Identification (RFID)
  Method of reading a card using radio frequency energy to transmit information. See Proximity.
• RAM
  See Random Access Memory.
• Random Access Memory (RAM)
  Randomly addressable, readable and writable memory.
• Read Only Memory (ROM)
  Non-volatile memory whose contents are programmed into the ROM when made, and therefore cannot be altered.
• Reader
  Device that receives an identification code from a card, key tag, or related item.
• Real Time Command
  Command that is executed immediately, with no time delay.
• Relay
  Device that is capable of opening a normally-closed circuit or closing a normally-open circuit.
• Request to Exit (RTE)
  Signal that informs the controller that someone has requested to exit from a secure area.
• REX
  Acronym for Request to Exit.
• RFID
  See Radio Frequency Identification.
• ROM
  See Read Only Memory.
• RS-232
  Serial communication protocol used for connecting data terminal devices.
• RS-485
  Serial communication protocol used for multi-drop communication applications.
• RTE
  See Request to Exit.

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S

• Secure Area
  Designated area in which access into and out of is controlled and can be monitored.
• Secure Door
  Door in which access through is controlled and can be monitored.
• Shielding
  Providing electrical isolation for a circuit, component, or wire by enclosing or isolating it with a metal enclosure.
• Short Circuit
  Unintentional connection that provides a low resistance path between two points in a circuit or to ground.
• Shunt
  [a] Deliberately shorting a portion of an electric circuit. [b] A device for shorting an electric circuit. See Short Circuit.
• Signature Verification
  Biometric identification method using a person's signature characteristics to identify that person.
• SPDT (Single Pole, Double Throw)
  Switch routing one input circuit to one of two output circuits.
• Spike
  Voltage peak of high amplitude and short duration. See Transients.
• SPST (Single Pole, Single Throw)
  Basic on/off switch that turns a single circuit on or off.
• Smart Card
  Identification card or access control card with a built-in integrated circuit chip.
• Suppression
  Addition of a device to an electrical circuit that minimizes or prevents transients.
• Switch
  Device used to either connect or interrupt an electronic circuit.

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T

• Tailgating
  [a] More than one individual entering a secure area using one access card. [b] Following an authorized person into a secure area. Also known as Piggybacking. See Anti Passback.
• Telephone Entry
  Access control system that allows users outside a secure area to use a telephone to contact someone inside.
• Timezone
  Specified period of time in which access is allowed.
• Touchpad
  See Keypad.
• Transients
  Electrical surges or spikes conducted through power or data lines. See: Suppression.
• Transorb
  Electrical suppression device. See: Suppression.
• Turnstile
  Entryway that uses a mechanical device to restrict entry to one person at a time.

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U

• UL
  Label signifying that the product has met the Underwriters Laboratories requirements.
• Upload
  Sending information from a peripheral device to the host computer in an access control system.

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V

• Verification
  Identifying an individual based on some type of provided information (e.g., access cards, biometric information).
• Voice Recognition System
  Access control system that verifies a person's identity by comparing previously stored voice recordings.

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W

• Wiegand Card
  Access control card based on the Wiegand effect. Small bits of specially processed wire are embedded in the card in a pattern that uniquely identifies the card.
• Wiegand Compatible Devices
  Proprietary coding format for information used by many suppliers of cards, key tags, proximity readers, and related items.
• Wiegand Effect
  Electrical pulses generated when individual sections of specially processed magnetic wire is passed by a pickup coil.
• Wiegand Reader
  Reader capable of reading the information encoded on a Wiegand card.

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X

• No current definitions.

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Y

• No current definitions.

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Z

• No current definitions.

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