IoT Connectivity Options: Comparing Short-, Long-Range Technologies

By Alex Makarevich

Connectivity is a critical piece of the IoT projects puzzle. Stakeholders need to find the most suitable connectivity option for their products and projects. With about 30 IoT connectivity options on the market today, their constant evolution and the development of new ones, this search can be difficult. New technologies such as LPWAN and 5G are gaining more attention, while others such as Bluetooth and Wi-Fi are evolving and thereby changing the IoT connectivity landscape. Let’s explore how not to get lost among the choices when choosing the best IoT connectivity option for your business.

To realize the potential of IoT, whole industries are working hard to develop the devices, and connectivity solutions to enable communication among the devices, in one ecosystem. It’s no easy task, for a number of reasons.

First, the amount of collected data is growing, and current solutions are increasingly challenged to handle the rising data volume.

In addition, IoT app developers and device manufacturers must provide for interoperability of all the elements of the IoT ecosystem. The ideal situation is to make all the devices work without any coordination required among vendors. So far appliance manufacturers are trying to preserve a certain level of control over connectivity standards, with Samsung, LG and other tech companies announcing their own standards. And though there is no doubt that these devices will be made interoperable, interconnectivity remains a serious barrier.

IoT developers and device manufacturers must also strike a balance between three key parameters: bandwidth, range and power consumption. Programmers are trying to create a solution that would be a perfect combination of high bandwidth for transmitting large amounts of data over huge distances while consuming little battery power. But, at this point, that perfect solution doesn’t exist. This means IoT developers must make trade-offs, perhaps prioritizing bandwidth over power consumption, or vice versa.

There is no one-size-fits-all protocol capable of supporting all technological and analytical tasks. But some solutions are better suited for specific use cases.

Classic Connectivity Solutions

The capacities of classic connectivity protocols are naturally limited to the expectations of past days, when the first IoT networks cropped up around smart home projects. Now these short-range wireless solutions are being modified and adapted to the new reality created by an avalanche of data from connected devices. Here we look at the traditional connectivity options, examining their advantages and disadvantages from the point of view of IoT projects.

Wi-Fi

Perfect solution for: data-intensive uses and in-building or campus environments, like home automation and house energy management.

Why? In most cases, Wi-Fi is 20 to 30 times quicker than Bluetooth Low Energy (BLE), making it a more suitable choice when the transmission of large files is needed.

Weak points: Transmitting large files comes at a cost of high power consumption. Wi-Fi was not designed expressly for IoT networks (though two recently developed IEEE standards, 802.11ah and 802.11ax, were). Sensors, key elements in IoT network development, are battery-based and transmit small amounts of data over huge distances. Consequently, they need  another type of connectivity solution.

Bluetooth and Bluetooth Low Energy

Perfect solution for: personal IoT devices like wearables and fitness trackers, as well as beacons.

Why? Bluetooth has long been popular in the consumer electronics segment for its ability to continuously stream large amounts of data. And BLE was designed specifically for low-powered IoT devices. BLE is best suited for devices that transmit low volumes of data in bursts, as the devices are designed to save power when they are not transmitting data.

Weak points: Its application in industrial projects has been limited because of its very short-range connectivity and high battery consumption. Still, the low price of this solution attracts developers, who have introduced hybrid architecture schemes with Bluetooth, which help to overcome the Bluetooth short-range restriction. These schemes use Bluetooth for connecting dozens of endpoint devices to one master access device. In turn, the access device uses another, more expensive technology (for example, cellular) for connecting to the back end (which is referred to as Bluetooth bridging).

Mesh Technologies

Perfect solution for: in-house applications and neighboring projects like smart lighting, security systems, HVAC systems and remote controls.

Why? Mesh technologies such as ZigBee and Z-Wave use a system of interconnected nodes to carry small data packets over short to midrange distances.

Weak points: Mesh technology can be challenging in some implementations. For instance, interoperability between Zigbee gadgets needs to be preplanned. With Z-Wave, however, communication between devices is easily accomplished.

IoT Rapid Development: New Protocols on the Market

New connectivity solutions are being developed to tackle the challenges of more complex IoT projects like smart cities, smart agricultural practices, smart metering and other entities, which demand a new level of connectivity standards.

LPWAN

Perfect solution for: massive IoT projects like smart cities or smart agriculture.

Why? Low-power wide-area network (LPWAN) is an umbrella term for any network that allows communication over large distances (at least 500 meters of signal range from the gateway device to the endpoint) using minimal power. These networks are divided into licensed (LTE-M, NB-IoT and EC-GSM) and unlicensed (SigFox and LoRa-based-standards).

These solutions have been designed particularly for IoT; therefore, they’re designed to send small amounts of data at longer intervals from a lot of endpoints, but within a long period (hence the need for low-power usage) and at longer distances.

Weak points: LPWAN technology is still in the early stages of deployment (the much discussed NB-IoT was presented only in 2016), and its full potential and disadvantages won’t become clear until the networks have been implemented at a greater scale. Today, only 20% of the global population is covered by an LPWAN network; that low uptake prevents it from becoming a default solution within the next five years. However, LPWAN availability is growing rapidly, and by 2022 LPWAN technologies are expected to provide coverage for 100% of the world population.

5G

Perfect solution for: the most bandwidth-intensive applications, remote surgery and massive machine-type communications.

Why? As IoT solutions will be getting more elaborate and emit more data, a demand for a larger bandwidth will only be growing, and 5G is expected to face this challenge. The first public networks are not here yet (they are expected to be made available in 2020), and we can only make predictions about how this fifth generation of mobile technologies’ extension to LTE technologies — already called “a game changer” by specialists — will function and how it will influence both software and mobile developers and end users. And these predictions are ambitious: By 2021, 5G’s broad enablement of IoT use cases is expected to drive a whopping 70% of Global 2000 companies to spend $1.2 billion on connectivity management solutions.

Weak points: Time will be needed to make 5G universal. Plus, we still need to wait and see whether the reality will correspond with the high expectations.

Making the Choice

There is ultimately no perfect connectivity solution for IoT. For massive and large IoT projects, you should consider hybrid solutions and build a suitable structure, where the benefits of one solution help overcome the limitations of the other.

In IoT, structures build upon combined connectivity protocols. LPWAN can, for example, provide for vast coverage of sensor endpoints, and Wi-Fi or BLE can be used for a local data-intensive processing of the collected packets.

Choosing the right IoT connectivity option for your business is not very difficult, but it does require  understanding certain technical issues and your business goals (type of the project, its future scaling and development). With those two issues addressed, making a connectivity choice becomes much easier.

Alex Makarevich is content manager at R-Style Lab, a custom IoT development company with an office in San Francisco and a development center in Belarus, Europe. She covers topics associated with IoT, web and mobile development.