The Internet of Things (IoT) refers to the vast number of internet-connected devices—“things”—that contain embedded sensors and software and which can connect via the internet to exchange data with other devices and systems. Grouping of IoT devices occur in consumer, commercial, industrial, infrastructure or military applications. Some examples are:
Early generations of IoT devices were passive, only passing information up to servers. There were privacy concerns, but not control concerns. More recent technology includes active devices which can receive commands, so concerns for security are added to prior privacy concerns. Many of the devices are battery-driven and are reached by low-power, low-data-rate radio signals using standard IEEE 802.15.4 technology.