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 38 names in this directory beginning with the letter A.
AAA
Authentication, Authorization, and Accounting (see also RADIUS).
ACaaS
Access Control as a Service.
Acceleration Sensing
A MEMS concept referring to the increase in movement of an object from one point to another along a straight line or axis. Typical applications include remote control, pointing devices, gesture recognition, fitness monitoring equipment, etc.
Accelerometer
A tool that measures changes in gravitational acceleration in the unit it may be installed in. Accelerometers are used to measure acceleration, tilt, and vibration in many devices.
Access Control
A system that determines who, when, and where people are allowed to enter or exit a facility or area. The traditional form of access control is the use of door locks, but modern access control may include electronic systems and wireless locks. Access control may also apply to cybersecurity.
Access Control as a Service (ACaaS)
A recurring fee-based system where a facility manager outsources electronic access control to a third party. Each facility need not maintain a dedicated server.
Access Point
A Wi-Fi node that allows users entry to a network, typically a LAN.
Active Sensor
A sensing device that requires an external source of power to operate.
Actuator
A device that introduces motion by converting electrical energy into mechanical energy in an electromechanical system. (An actuator may also stop motion by clamping or locking.) A dynamo is an example of an actuator.
ADAS
Advanced Driver Assistance Systems.
Additive Manufacturing
The industry-specific term for 3D printing, involving building products by adding layers rather than the traditional technique of removing material via milling.
Addressability
The capacity for an entity to be targeted and found. To be addressable, an entity must be uniquely identifiable, meaning that it must be associated with something — typically an alphanumeric string — that is not associated with anything else that exists within that system.
Advanced Driver Assistance Systems (ADAS)
Digital features incorporated into vehicles to enhance driver safety and performance. ADAS functionality includes digital vision for lane departure warnings, blind spot detection, radar for collision avoidance, and V2V communication for multiple vehicles operating near each other. The data and connectivity integral to ADAS transforms vehicles into IoT devices.
Advanced Encryption Standard (AES)
The specification for encryption of electronic data established in 2001. Operates on a public/private key system, and planning for key management is an important aspect when implementing AES encryption.
Advanced Message Queuing Protocol (AMQP)
An open-source standard for business message communication. Main features include message orientation, queuing, routing, reliability, and security.
Amazon Web Services (AWS)
The name given to a collection of remote computing services, offered by Amazon.com, that combine to make a cloud computing platform.
Ambient Assisted Living (AAL)
Intelligent systems to assist the elderly and others with daily care activities, often through IoT technology. Application fields are security (for example, observation), functionality (such as automated light switches), and even entertainment.
Ambient Intelligence (AmI)
Sensor-filled environments that interpret and react to human events and activity, and learning to adapt over time, the environment’s operation and services change based on that activity.
AMPS
Advanced Mobile Phone System, an analog cellular mobile system using FDMA.
AMQP
Advance Message Queuing Protocol.
Android Wear
An open-source platform that extends the Android system to wearables. The SDK includes an emulator.
Anomaly Detection
A statistical technique that determines what patterns are normal and then identifies items that do not conform to those patterns. Unlike simple classification where the classes are known in advance, in anomaly detection the users don’t know what they are looking for in the data.
ANSI-136
American National Standards Institute Standard 41, for TDMA cellular.
ANSI-2000
American National Standards Institute Standard 41, for CDMA2000 cellular.
ANSI-41
American National Standards Institute Standard 41, for control signal messaging on SS7.
ANSI-95
American National Standards Institute Standard 41, for CDMA cellular.
AP
(Wireless) Access Point.
API
Application Programming Interface.
Application Programming Interface (API)
A collection of commands and protocols used to interact with an operating system, device, or specific software component. In IoT, an API lets the developer access the functionality of a device or sensor, such as a thermometer’s readings. APIs can be public or restricted to authorized users only.
Application Software
Programs that enable specific, end-user actions. This means the software uses the given potential provided by computers to form an application. Examples include Microsoft Word (text editing), Adobe Photoshop (image editing), and many other programs.
Application Specific Sensor Nodes (ASSN)
Integrating sensors and sensor fusion in a single device, ASSNs have a built-in intelligence to cope with the complexity of applying multiple sensors to a specific problem such as augmented reality, navigation, positioning, and more. Bosch Sensortec
Arduino
A single-board microcontroller used for prototyping without having to deal with breadboards or soldering. The software to operate an Arduino is free and open source.
ARP
Address Resolution Protocol. A communication protocol used to convert an IP address into a physical address. This way, computers can communicate with each other, despite only knowing each other’s IP addresses, by sending an ARP request that informs them about the other computer’s MAC address.
AT Commands
Attention commands, developed by Dennis Hayes, that are used to set data connections. The set of short string commands allow developers to set up calls with a modem, as well as perform far more complex tasks. For an example of an AT command set, take a look at Telit’s 3G module, the HE910, AT command directory.
Audio Profile
Hardware profile used with Bluetooth applications that include custom AT commands and functionality dedicated to wireless streaming of audio. Examples include A2DP, which allows for streaming of audio to devices such as speakers, where as an audio gateway profile allows for two-way audio communication used in devices such as headsets.
Augmented Entity
A physical entity is represented by a virtual entity on the digital level. An augmented entity combines the two and stands for any combination of the two entities.
Automated Identification and Mobility (AIM) Technologies
A group of technologies that are used to identify, store, and communicate data. An example would be a barcode, though there are many technologies in this area that are used for different services and are often used in combination.
AWS
Amazon Web Services.