Which IoT network should smart cities and businesses use?
Our IoT devices work by retrieving fill-level data from containers and bins. This data is then sent or stored on the internet. To enable this communication, a connectivity or network layer is required that establishes the connection between an IoT device and higher abstraction layers, such as the application layer or the internet.
The IoT smart bin sensors from WasteHero supports multiple networks, namely: GSM, Sigfox, LoRaWAN & NB-IoT. The following article will discuss the pros and cons of each network to help you determine which network is the best fit for IoT smart cities and businesses.
LPWAN (Low Power Wide Area Network)
Sigfox, LoRaWAN and NB-IoT are all valid options for IoT devices and can all be classified as LPWAN (Low Power Wide Area Network). LPWAN refers to networking technologies that rely on low-power radios for communication and can cover a large geographical area.
These networks are becoming increasingly popular, as network operators are developing horizontal networks for machine-to-machine solutions by means of LPWAN.
Common characteristics of LPWAN technologies is the low power consumption, high communication range and low data rate, which makes them an excellent fit for IoT devices, since these often do not send data continuously, are battery-powered, thus requiring low power consumption electronic and can be placed far from each other.
Thereby, a high communication range is beneficial. In addition to the LPWAN networks, this article will include mobile GSM technology as it provides the best coverage as of now.
LoRaWAN (Long Range Wide Area Network)
LoRa is a patented wireless technology that was developed by Cycle of Grenoble and later acquired by Semtech in 2012.
The coverage of LoRaWAN greatly depends on the site and implementation, as anyone can basically set up a LoRaWAN network, by purchasing some gateways and using one of the network infrastructures, such as The Things Network (TTN) or Loriot.
There is coverage present in more than 100 countries, with 50 public network operators and more than 450 members in the LoRa Alliance.
Figure 1 - LoRa Alliance coverage map
It is a technology that offers a low power, long-range connectivity solution, which is open-source, low-cost and well-tailored to IoT communications.
On the flip side, it is however dependent on having a gateway infrastructure set up and maintained. This means that the entire network relies on the set-up of gateways.
It does, however, provide the option to set-up and manage your entirely own network without monthly subscription fees.
There is a certain cost associated with the implementation of a LoRaWAN gateway infrastructure, a lot of maintenance and security that must be done internally, however you will have your own network with beneficial capabilities, which is free of charge after the implementation of gateways.
Sigfox is a proprietary technology developed by the French Sigfox company, offering a world-wide subscription-based LPWAN service. It is defined as an end-to-end communication solution, which has built up a communication infrastructure and connectivity solution developed to serve the low throughput Machine to Machine (M2M) and IoT areas.
Sigfox claims to support up to a million connected devices in a network and coverage of 30-50 km in rural and 3-10 km in urban areas. A case study of the Sigfox coverage concluded that 97 % of the transmissions were successful from 400 measured spots.
Sigfox is currently operating in 45 countries with more than 3.8 million km2 coverage. Sigfox states that worldwide coverage is available, however, the live coverage is mostly limited to Western Europe, parts of North and South America, Middle East, South Africa, Japan and Australia.
In the coverage map below, the light blue is the live coverage, while the purple is under-rollout.
Figure 2 - Sigfox coverage
Sigfox offers a low-cost, low-energy consumption means of transporting data, across a long-range and the underlying infrastructure for the network coverage is covered by Sigfox, thereby insuring its uptime and availability.
Sigfox also offers localization, through triangulation and WiFi, which is not an accurate location method (1-10 km, 80 % of the time). On the flipside, Sigfox limits devices to 140 messages a day, the specifications are not open source and sending messages requires a cost.
NB-IoT (Narrow Band)
NB-IoT is a radio technology, which was standardized by the 3rd Generation Partnership Project (3GPP) in June 2016. NB-IoT technology inherits the core functionalities from LTE, and its design allows it to coexist well with GSM and LTE systems.
With a software upgrade, the basic network elements of network providers existing LTE network can support NB-IoT.
The NB-IoT standard was developed to improve indoor coverage, support a large number of devices with low throughput, ensure low delay sensitivity, low device costs, low power consumption and optimized network architecture.
NB-IoT is still in a rather embryonic state, however, it is expected that we will see a worldwide coverage in the coming years, with network providers rapidly expanding. Below is a map of the current 4G/LTE coverage, where a software upgrade can allow for NB-IoT networks:
Figure 3 - 4G/LTE Coverage map
NB-IoT offers wide-area coverage, the ability to quickly upgrade existing networks, low power consumption with battery lives of up to 10 years, low-cost terminals, highly reliable transmissions, however since NB-IoT goes through a base station owned by a carrier, it is a paid service.
GSM (Global Systems for Mobile Communications)
Global System for Mobile Communications (GSM) is a standard that was developed by the European Telecommunications Standard Institute, with the goal of describing the second generation of digital cellular networks that can be used by mobiles devices to connect to the internet.
GSM was first deployed in Finland in 1991 and has since become a global standard with over 90 % of the total market. GSM is used by more than 6 billion people and is present in more than 219 countries across the world.
GSM offers the largest worldwide coverage:
Figure 4 - GSM World Coverage Map
GSM connectivity through GPRS, 2G, 3G or 4G currently offers the best worldwide coverage and a wide range of hardware than can be used to connect to the networks. Furthermore, GSM provides a stable and well-tested network.
On the other hand, most 2/3/4G devices cannot compete on the power consumption with LPWAN modems and the additional cost of a subscription and having a SIM-card are not desirable.
Below is a table comparing the discussed networks:
Choosing the right IoT network for smart cities and businesses
Choosing the correct network depends on the specifications of the project and the location.
LoRaWAN offers a significantly cheaper network on a monthly basis with the lowest power consumption, however, the initial investment required to set up the gateways might not be desirable.
Sigfox also offers a low power consumption, a wide range of connectivity, however, it is required that you pay a subscription fee for the network. Furthermore, the coverage is limited, therefore Sigfox might not always be an option.
NB-IoT offers a very stable infrastructure and network with the best range and connectivity, especially for deep indoor use, which could be relevant for underground containers to reach a stable signal. NB-IoT is however like Sigfox a subscription, where you must pay a monthly subscription to the provider.