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 34 names in this directory beginning with the letter M.
M2M
Machine-to-Machine.
M2P
Machine-to-Person.
Machine Authentication
The authorization of an automated human-to-machine or machine-to-machine (M2M) communication through verification of a digital certificate or digital credentials. Unlike user authentication, the process does not involve any action on the part of a human.
Machine Data
Also known as machine-generated data, this is digital information created by the activity of computers, mobile phones, embedded systems, and other networked devices.
Machine Type Communications (MTC)
A 3rd Generation Partnership Project (3GPP) standard describing machine-to-machine communications. With a wide range of potential applications, MTC communications is gaining interest among mobile network operators, equipment vendors, specialist companies, and research bodies.
Machine-to-Machine (M2M)
A broad term describing technology that allows for one connected device to communicate and exchange information with another connected device, without the assistance of a human.
Machine-to-Person (M2P)
Describes the analytics for big data in a human readable form (e.g., dashboards).
MapReduce
A parallel processing model for handling extremely large data sets. First, a Map process runs to reduce a data set to key value pairs (in tuples), and then a second Reduce process combines those pairs into a smaller set of tuples. First introduced by Google, MapReduce is a concept central to Hadoop.
MCU
MicroController Unit.
MDN
Mobile Directory Number (used in CDMA — conceptually similar to the MSISDN in GSM).
Mechatronics
A combination of the words “mechanical” and “electronics,” mechatronics brings together electrical engineering, control engineering, computer engineering, and mechanical engineering disciplines. A warehouse inventory robot would be a mechatronic device, whereas an IoT-enabled sensor device, such as a weather station, could be better classified as a Cyber-Physical System (CPS).
Media Access Control (MAC)
The “layer 2” in a network that allows the physical medium (radio waves or wire signals) to be organized to pass data back and forth. For low-rate data wireless applications, the MAC has many implications on performance.
MEID
Mobile Equipment Identifier (used in CDMA).
MEMS
Micro-Electro-Mechanical Systems.
Mesh Networking or Mesh Network Topology
An ad-hoc, local area network infrastructure where the nodes communicate directly with each other without the need to pass through a central structure such as an ISP. The only way to shut down a mesh network is to eliminate every node. One of the most dramatic demonstrations of mesh technology was during the Hong Kong protests in October 2014 where the direct communication between protestors’ devices confounded the government’s ability to block communication. The adaptivity of mesh networks makes them ideal for IoT applications.
Message Broker
A middleware program that translates a message from the messaging protocol of the sender into the messaging protocol of the receiver. This way a message broker makes it easier for two applications to communicate.
Message Queue Telemetry Transport (MQTT)
An open, lightweight M2M communications protocol for the transfer of telemetry messages.
Message-Oriented Middleware (MOM)
Middleware that allows for synchronous as well as asynchronous (queue) messaging between distributed systems.
mHealth
Mobile Health. This is the practice of medicine using mobile devices, particularly physiological sensors. Sensors may be enabled to communicate with a user’s mobile phone in a Body Area Network configuration. Related to e-Health.
Micro-Electro-Mechanical Systems (MEMS)
Miniaturized mechanical and electro-mechanical elements, typically used for measurements, such as accelerometers and gyroscopes. Systems-on-a-chip (SoC) technology is used to embed mechanical devices such as fluid sensors, mirrors, actuators, pressure and temperature sensors, and vibration sensors on to semiconductor chips.
MicroController Unit (MCU)
A full computer on a single chip. The chip contains a CPU, a clock, non-volatile memory for the program (ROM or flash), volatile memory for input and output (RAM), and an I/O control unit.
MIMO
Multiple Input, Multiple Output (in the context of antennas).
MNO
Mobile Network Operator.
Mobile Network Operator (MNO)
Companies that operate traditional mobile communications networks.
Mobile Virtual Network Operator (MVNO)
A wireless communications provider that leases the infrastructure over which it proves services.
Modbus
A communication protocol mainly used to connect electronic devices. The Modbus Master (for example, a computer) requests information from the Modbus Slaves (for example, electronic thermometers). Up to 247 Slaves can transmit their information to one Master.
Mote
Short for Remote. A mote is a wireless transceiver that also acts as a remote sensor.
MQTT
Message Queue Telemetry Transport.
MS
Mobile Station (cellular radio handset or cellular M2M device).
MSC
Mobile Switching Center.
MSISDN
Mobile Station ISDN (used in GSM).
MTC
Machine Type Communications.
Multiple DoF Sensing
A MEMS concept referring to the detection of the combined input along multiple axes using multiple sensing types, such as acceleration and rotation. Typical applications include antenna stabilization, robotics and dead-reckoning.
Multiple-Input and Multiple-Output (MIMO)
A radio technology using multiple antennas at both the transmitter and receiver to improve communication performance. MIMO is an important part of wireless communication standards such as IEEE 802.11n (Wi-Fi).