Internet of Things 'IoT'
The Internet of things (IoT) is the network of physical devices, vehicles, and other items embedded with electronics, software, sensors, actuators, and network connectivity which enable these objects to collect and exchange data.
Each IoT devices needs to communicate with an end user, another device or human. For this we use many types of communication, taken from the IT world. Data can be both sent to and recieved from IoT devices. IoT devices may have a backup medium for logging data while not connected to your network. This is also used when the data volume is to high for transmition.
Short Range 'IoT' communications methods
Wi-Fi or WiFi is a technology for wireless local area networking with devices based on the IEEE 802.11 standards.
Bluetooth is a wireless technology standard for exchanging data over short distances from fixed and mobile devices, and building personal area networks.
An example of Bluetooth used with IoT is with BLE adverts. See https://seaa.me/ project for details.
NFC - NEAR FIELD COMMUNICATION
Just like Bluetooth and WiFi, and all manner of other wireless signals, NFC works on the principle of sending information over radio waves. The technology used in NFC is based on older RFID (Radio-frequency identification) ideas, which uses electromagnetic induction in order to transmit information. NFC
NFC and Bluetooth: the Perfect Pair
From wearables to smart appliances, NFC’s tap and go functionality helps consumers simplify device operation, enabling multiple devices to easily connect and to work together. NFC
Long Range 'IoT' communications methods
LoRa stands for Long Range and it is a technology that uses unlicensed spectrum below 1GHz along with a form of direct sequence spread spectrum modulation that provides signal detection below the noise level.
LoRa® Product Family from Semtech.
Modems as Peer's
The 'peers' are computer systems which are connected to each other via communications. This can be peer to peer or peer's to gateway.
Gateway for peer's
The gateway here is the interface between the IoT world & the IT world. This is the key point in security design. Not to allow the IoT to talk to the IT world directly or vice versa.