IoT Dictionary

This glossary includes key terms of the IoT (Internet of Things) & M2M (machine-to-machine) communications industry, including wireless and cellular technologies spanning many different markets. It is updated to present current terminology and usage. Your participation and feedback are most welcome—to submit comments, new entries, or suggestions, contact us today.

# 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
There are 30 names in this directory beginning with the letter P.
Personal Area Network.
Part 90 Bands
Small parts of the RF spectrum that are made available in small areas to businesses for data or voice communications. Many smart grid providers use part 90 licenses for their wireless data.
Passive Sensor
A device that detects and responds to some type of input from the physical environment.
Printed Circuit Board.
Pedestrian Dead Reckoning.
Power Distribution Unit.
Pedestrian Dead Reckoning (PDR)
A method of indoor positioning that uses a last known waypoint, distance, and direction of travel to calculate the current location of a moving person. PDR may be used to supplement other positioning methods such as GPS. Dead reckoning is subject to cumulative errors.
Pen Testing or Pentest
Penetration Testing.
Penetration Testing
A method of evaluating the security of a network or system from internal or external threats. Also called pentests, this is part of a full security audit and typically exploits a combination of weaknesses to gain access and then evaluates the capability of the network’s defenders to detect and respond to the penetration.
Personal Emergency Response System.
Personal Area Network (PAN)
Interconnected devices operating in the range of a single person, typically 10 meters. PANS are mostly or exclusively wireless, making the term basically indistinguishable from Wireless PANs (WPAN). WPAN is based on the IEEE 802.15 standard and does not necessarily require an uplink to the Internet. The PAN concept was first developed by Thomas Zimmerman and others at the M.I.T. Media Lab.
Personal Emergency Response System (PERS)
A mobile duress panic alarm component of a monitoring system, typically for the residential market. Modern PERS devices go beyond their origins as a mere push button to include MEMS and various other sensors.
Personal Protection Drone (PPD)
A type of drone, or drone swarm, dedicated to an individual’s security. PPDs are non-lethal and may be primarily used to record an encounter or raise an alarm. A use case for a swarm of PPDs may be to hinder the approach of an assailant long enough to facilitate the protected person’s withdrawal.
Pervasive Computing
Another term for ubiquitous computing.
Photoplethysmogram (PPG)
A optically obtained plethysmogram using an LED that measures the output volume of an organ, such as the heart. A photodiode measures the amount of light reflected from the LED, which in a heart monitoring application can be translated into a waveform. Respiration can induce variations in the amplitude of the PPG waveform.
Physical Web, The
Google’s open standard to allow IoT devices to communicate via web addresses. By using HTTP, users can walk up and access any smart device (such as parking meters and vending machines) without the overhead of dedicated mobile apps.
Platform as a Service (PaaS)
A platform that provides web developers with all the infrastructure they need to develop and run an application.
Power over Ethernet.
Power Distribution Unit (PDU)
A physical device with multiple outlets that connects electrical power to recipient devices. PDUs can be simple, such as a mounted power strip, or more complex by having power filtering, UPS, load balancing, or intelligent monitoring incorporated in the device.
Power over Ethernet (PoE)
The capability to deliver enough power to operate a device over an Ethernet connection. PoE is useful in certain low-voltage applications, such as passive IP cameras.
Personal Protection Drone.
Point-to-Point Tunneling Protocol. This is a method for implementing virtual private networks (VPNs).
Preboot Execution Environment (PXE)
The ability to manage power over a network connection. A PXE-enabled device can be shut down or restarted via a network connection, allowing for power-hungry devices to be managed remotely.
Private Cloud
A private cloud provides services with cloud characteristics but only within a single organization, for example, one company.
Public Cloud
In a public cloud, cloud services are public and made available for everyone.
Pulse Oximeter
A sensor that measures oxygen saturation in the blood. Saturation of peripheral oxygen, or SpO2, is a measure of hemoglobin saturation and can be measured non-invasively, for example, with a clip on the finger or ear. The sensor typically employs a pair of small LEDs facing a photodiode that measures the amount of light passing through the skin.
Preboot Execution Environment.
A widely used open-source programming language that can be implemented in variety of ways, including in embedded applications. There is a large library base which can be used by Python applications, helping minimize code and speed up development time.
Python Script Interpreter
A tool that lets you run Python code, something which is now being seen embedded directly into devices such as cellular modules.