IoT and Connectivity - A practical review

What is the “Internet of Things” (IoT)?

As connectivity becomes ubiquitous, industry has explored several technologies to provide seamless communication to devices. These devices could be in any setting, from industrial water pumping stations to domestic appliances such as fridges and kettles.

Some connectivity options like WiFi and Bluetooth already exist, like, however, these have some limitations. For example, in range and power consumption. This means that additional technologies needed to be explored.

What will it be used for?

In many cases, the amount of data needing to be exchanged with a device is very small and only need to be sent infrequently. A sensor in a Council rubbish bin for example, could transmit a data packet once or twice a day to update a database. This could provide Council operatives with a schedule of bins that need to be emptied. A parking sensor embedded in the tarmac of a parking space may need to transmit data a bit more frequently, but probably no more that 20-40 times a day. These are relatively lightweight transactions, and this has been incorporated into the IoT design philosophy, where battery-operated devices using narrowband signals can send data for many years over significant distance, without needing a battery replacement.

What are the IoT technologies?

There are two main categories of technology emerging: Cellular based IoT using two main technologies, Narrowband IoT (NB-IoT) and LTE-M, and devices using unlicensed spectrum that centre around another two main technologies, LoRaWAN and Sigfox. In the UK, unlicensed devices operate primarily in the 868MHz band.

The term “Low Power Wide Area Network” (LPWAN) refers to all these technologies. The receive power thresholds for LPWAN devices are extremely low-level. This is the key that enables a low power transmitter (e.g. 25 milliwatts) to be received many kilometres away.

LoRaWAN offers complete control over infrastructure and devices, providing the ability to create an entirely private network. Sigfox on the other hand retains control of the Network Infrastructure, although this infrastructure is provided in an “on demand” basis. This has the advantage that the users do not need to own or maintain infrastructure, but also do not have control of it. Sigfox has a much narrower bandwidth than LoRa, with the result that the data-rate is much lower, numbers of messages per day is restricted by the operator. One advantage of the narrower bandwidth is that the range is significantly better, with a potential of up to 40Km in a rural environment, as opposed to 20Km with LoRa.

NB-IoT is a technology that incorporates IoT devices into mobile (cellular) networks. Standards have been defined by the Third Generation Partnership Project (3GPP). The focus again is on low power devices with long battery life, however, the bandwidth available is significantly higher. The range of NB-IoT devices is generally shorter than those of LPWAN devices, with a potential of up to 10Km in a rural environment. Plans for 5G have a specific focus on IoT and it’s likely portions of spectrum will be reserved for this application.

NB-IoT and LPWAN are complementary technologies that can co-exist and will play a significant role in our future connected world.

How will IoT impact businesses and Public Services?

Sensor devices are currently available off-the-shelf for LoRaWAN and Sigfox and can be incorporated into private or public IoT networks. As numbers of devices grow and when the cellular networks are rolled out to provide complimentary coverage, the vision is that the cost of the IoT radio devices will become so small that they will be incorporated by default into most consumer and business electronics.

The landscape is still at an early stage and it’s difficult to enter the arena without getting bogged down in code and technical minutiae. That will of course change over time and the technology will become more accessible as a result. What remains to be seen is where the real advantages lie. There are many clear examples of those advantages providing potential efficiency improvements, such as monitoring of Council bins and public space utilisation. However, with the forecast of ubiquitous connectivity to consumer devices, the security aspect needs serious consideration and already, existing IoT devices have poor reputations for security.

How many devices do we feel a need to manage and how big a threat is the unmanaged connectivity? There are potentially real advantages for health care in improving efficiency within hospitals and monitoring of patients in their own homes, but we should also be cautious about storing up a headache for the future.