Numerous types of Internet of Things (IoT) connectivity technologies exist, some well-established and others just emerging in the market. Choosing a wireless solution is one of the most important decisions a company makes when deploying IoT devices. The network capabilities of the many wireless technologies can vary greatly, making it imperative to ensure the right solution is being selected for your unique IoT environment. At the same time, wireless connectivity vendors must understand how their solution(s) hold up against the competition.

This article is a valuable resource for both enterprises and connectivity vendors, providing an in-depth overview of the most prominent types of IoT connectivity. I will walk you through the pros and cons of short-range and long-range solutions, and then make the case for combining them to enhance IoT outcomes. But first, let’s define IoT connectivity and identify the most important technical specifications that should be evaluated during the selection process.

What Is IoT Connectivity?

IoT connectivity is the way in which IoT devices can connect with one another and the wider IoT ecosystem. These devices encompass sensors, trackers, tags, gateways. wearables, Augmented Reality (AR)Virtual Reality (VR) glasses, smart home appliances, and meters, among others. Connectivity is essential for these devices to communicate with each other and other systems to enable key data capture and exchange. For this article, IoT connectivity also includes the technologies that enable connectivity. These technologies fall under the Short-Range Wireless (SRW) and Low-Power Wide Area (LPWA) categories.

IoT connectivity is essential in data-driven decision-making. IoT devices collect a wide range of data that can provide a window into enterprise operations, including the location of assets, the health condition of industrial machinery, or the temperature of food containers on a truck as a few examples. Of course, connectivity is also important for consumer IoT applications as well, such as fitness trackers, home security, smart appliances, and more.

Key Factors When Choosing an IoT Connectivity Solution

When choosing an IoT connectivity option, businesses should evaluate the solution’s range, maximum data rate, channel bandwidth, and spectrum band. Evaluating these technical specifications will help you choose a technology that best fits your organization’s connectivity needs and target applications.

• Range: What geographic range does the connectivity technology support? Do some countries in which you operate have limited or no access to certain protocols?
• Maximum Data Rate: How much data can the solution transmit over the network, and how much does your IoT application require?
• Channel Bandwidth: What range of frequencies can the connectivity technology support?
• Spectrum Band: Which spectrum frequency bands are leveraged?
• Key Applications: Which connectivity technology, given its specifications, can best support your business’ target applications?

While these technical specifications are key criteria for choosing a connectivity solution for the IoT, businesses must also consider cost, scalability, ease of use, and the installation process.

Short-Range Wireless Connectivity Technologies

SRW networking technologies are best suited for small environments where IoT applications do not require an expansive connectivity range. For example, smart home appliances only require IoT connectivity within a small geographic area. Three of the foremost SRW networking technologies are Bluetooth^®, Wi-Fi, and Zigbee.

Bluetooth®

Bluetooth^® is one of the most popular forms of IoT device connectivity, often used in consumer products such as headphones, laptops, smartphones, and wearables. Bluetooth^® 5.0 and Bluetooth® Low Energy (LE) have presented significant upgrades for IoT applications. When the former was released in 2016, it increased the technology’s data rate, range, and bandwidth. Meanwhile, Bluetooth^® LE allows IoT devices to connect with one another at a smaller energy footprint, making it more cost-effective than Bluetooth^® Classic. The introduction of Bluetooth^® mesh in 2017 was another major milestone, expanding the number of IoT devices a Bluetooth^® network can support.

Below are the pros and cons of using Bluetooth^® for IoT applications.

Pros

• Already widely familiar, Bluetooth^® is deployed in numerous connected device applications (e.g., home security and automation).
• Bluetooth^® LE is an alternative  to Wi-Fi for short-range devices that don’t have high data throughput requirements.
• Bluetooth^® mesh excels in IoT-based asset tracking use cases.

Cons

• Without being paired with long-range technology, Bluetooth^® connectivity can be restricted to small spaces.
• Bluetooth^® Classic and Bluetooth^® LE do not scale well and sometimes lack support for the device densities an Industrial IoT (IIoT) application requires.
• Bluetooth^® mesh is perceived as the runner-up to Zigbee in larger deployments, with Zigbee being a more mature technology.

Wi-Fi

Wi-Fi has historically struggled to find traction in the IoT space, as the technology was not designed for power conservation. However, Wi-Fi HaLow and Wi-Fi 6  have improved Wi-Fi’s appeal to IoT users. Wi-Fi HaLow, released in 2017, extended IoT devices' range and battery life, while supporting connectivity through walls and other physical barriers. HaLow really stands out in its use of sub-1 Gigahertz (GHz) bands and its ability to achieve a range of over 1 Kilometer (km). These are significant upgrades over most Wi-Fi solutions that run on 2.4 GHz or 5 GHz bands and hold ranges of roughly 100 Meters (m). Wi-Fi 6, while limited in range compared to Wi-Fi HaLow, provides improved connectivity speed and is reliable in multi-device settings.

Pros

• Wi-Fi is ubiquitous and present in millions of buildings and homes worldwide.
• Inexpensive and very accessible for short-range, data-intensive IoT applications.
• Wi-Fi HaLow has a wider range, higher data throughput, and lower power consumption than other Wi-Fi protocols and can support IoT applications, which LPWA technologies have yet to address.
• Wi-Fi is better at providing connectivity through obstacles than Bluetooth^® and other SRW technologies.

Cons

• Despite the advancements of Wi-Fi HaLow, well-established long-range wide area network technologies (e.g., cellular connectivity, LPWAN, and LoRa) are supported by a robust, global device ecosystem and already address many of the applications for which Wi-Fi HaLow was designed.
• Supporting video is a key differentiator for Wi-Fi HaLow. However, video surveillance camera users fear that wireless cameras carry a high risk of connection interruption and are, therefore, less inclined to invest in Wi-Fi-supported devices.

Zigbee

Zigbee is another prominent SRW connectivity option for IoT applications and has been around since the early 2000s. Zigbee is based on the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 wireless specifications. The technology performs best in IoT applications with short-range connectivity requirements and low data rates (e.g., home automation, wearables, smart metering, etc.).

Zigbee has a typical range of 10 m to 100 m and runs on the 2.4 GHz frequency band or the country-specific frequency bands 784 Megahertz (MHz), 868 MHz, and 915 MHz.

Pros

• Zigbee is suitable for short-range, low-power IoT devices.
• Zigbee supports star and mesh topologies.
• It is a well-established technology with the Zigbee Alliance providing ongoing oversight.
• Zigbee is more scalable for IoT deployments than Bluetooth^® LE due to handling more endpoints.

Cons

• Zigbee has limited geographic range.
• It struggles to support IoT applications with high data rates.

Figure 1: Specification Comparison Chart for Short-Range Wireless Technologies for the IoT

(Source: ABI Research)

Learn more in ABI Research’s free whitepaper, The Continued Evolution of Short-Range Wireless New Technologies, Future Enhancements, and Emerging Market Opportunities.

Low-Power Wide Area (LPWAN) Connectivity Technologies

More and more IoT deployments transmit small amounts of data across vast distances, with water/gas metering, smart city, agriculture, and environmental applications being prominent examples. These applications require long battery life so that businesses are able to sidestep the need for frequent battery replacement throughout the device lifecycle. LPWAN connectivity serves these business interests, providing a wider coverage than SRW technologies, while excelling at battery conservation. LPWA wireless technologies are split between cellular and proprietary solutions.

Cellular LPWA technologies include Narrowband Internet of Things (NB-IoT), LTE-M, and LTE Cat-1, forming the first LPWA connectivity technologies category. IoT users will appreciate the ability of cellular coverage to support previously unsupported areas and the fact that it runs on licensed bands to mitigate channel interference.

The second category consists of proprietary LPWANs, particularly LoRaWAN and Sigfox. Private companies or organizations provide proprietary LPWAN technologies and operate in unlicensed bands. While new LPWA proprietary solutions such as MOITY and ZETA have recently entered the market, ABI Research has focused on the more established LoRaWAN and Sigfox technologies. Sigfox has lost prominence, recently filing for bankruptcy, and being acquired by UnaBiz. For this article, we will focus more on LoRaWAN for proprietary LPWA.

Cellular LPWA (NB-IoT, LTE-M, and LTE-Cat-1)

As previously mentioned, the three primary cellular LPWA technologies used for IoT applications include NB-IoT, LTE-M, and LTE Cat-1. The following list provides context for these technologies.

• NB-IoT: Our analysts assess that NB-IoT connectivity is best used in static applications with small, minimal data transmission. While restricted to 200 kHz bandwidth, NB-IoT devices are typically uncomplicated and can achieve a life span of up to 10 years if used seldomly (less than once per day). NB-IoT users report reliable indoor and underground cellular coverage.
• LTE-M: While LTE-M and NB-IoT have similar battery lives, the former offers IoT users connectivity advantages. LTE-M has a faster data rate, can store more data in a single packet, and achieves lower latency than NB-IoT. These advantages make LTE-M the better option for consistent, data-intensive applications. It’s also worth noting that, unlike NB-IoT, LTE-M supports cellular handoffs.
• LTE Cat-1: As an LTE protocol, LTE Cat-1 has broad global coverage, making it ideal for IoT device manufacturers shipping to various international markets. The connectivity technology also leverages the same cellular roaming agreements as other LTE categories. LTE Cat-1 was introduced with The Third Generation Partnership Project (3GPP) Release 8, designed from the ground up for IoT and Machine-to-Machine (M2M) communication. As pointed out in a recent blog post from ABI Research, a significant development for the single-antenna version of Cat-1—Cat-1bis—is underway.

Pros

• Cellular LPWA technologies provide sufficient coverage area and battery life for many IoT use cases.
• It is less prone to channel interferences due to using licensed bands.
• LTE Cat-1 has wide availability, is tailored for IoT use cases, and is seen as a solid replacement for 2G and 3G devices.
• IoT customers can choose from a variety of options depending on use case, budget, data/power requirements, and other factors.

Cons

• Cellular LPWA availability is impacted by region, with areas in Asia lacking LTE-M availability
• Costs can get high as cellular devices are typically more expensive than other LPWA technologies.
• Cellular LPWA users outsource network management to Mobile Network Operators (MNOs), and as a result, have less control over their network’s performance.
• LoRaWAN and other low-cost, low-power technologies are seen as viable alternatives to NB-IoT devices.

LoRaWAN

With Sigfox hitting some financial hurdles recently, this has opened an even wider path to market for the already well-established LoRaWAN connectivity technology. LoRaWAN, which Semtech owns, is one of the most commonly used LPWA technologies. Besides its relatively low cost and low power requirements, part of the technology’s appeal comes from its backing from the powerful companies and nonprofits that make up the LoRa Alliance. The LoRa Alliance ensures interoperability between IoT devices and builds awareness of the technology’s benefits. Enterprise customers are often skeptical of technologies controlled by a single entity, making the collaborative nature of the LoRaWAN Alliance a key factor.

Perhaps the biggest appeal of LoRaWAN for IoT applications is that the technology can be deployed in both private and public networks. This is a huge benefit for enterprises that want to deploy each type simultaneously. Despite its appeal, LoRaWAN has some drawbacks, such as higher latencies and a massive IoT threat from Wirepas’ 5G mesh technology. However, LoRaWAN’s expansive range, ultra-low power, and flexibility make the technology competitive in use cases requiring low data transmission over scattered areas, such as smart cities, smart buildings, and asset tracking.

Related Blog: Key IoT Trends and Statistics Foreshadowing the Future 

Below are the pros and cons of using LoRaWAN for IoT applications.

Pros

• LoRaWAN has a strong ecosystem and backing from the LoRa Alliance.
• Unlike 2G, 3G, and even 4G LTE, LoRaWAN does not face the threat of future sunsetting, making it a more reliable long-term IoT connectivity solution than cellular technologies.
• It provides a high level of deployment flexibility.
• LoRaWAN’s technical specifications make it less resource-intensive than NB-IoT and cheaper than other cellular networks.

Cons

• Providing an integrated, easy-to-use connectivity solution for the IoT can be challenging with LoRaWAN, similar to other connectivity technologies.
• Higher latency (seconds) eliminates LoRaWAN from competing with other connectivity technologies for mission-critical use cases requiring delivery within milliseconds.
• LoRaWAN’s foothold in the massive IoT space could be threatened by Wirepas’ 5G mesh solution in the future.

Figure 2: Specification Comparison Chart for Low-Power Wide Area Network Wireless Technologies for the IoT

(Source: ABI Research)

Satellite IoT

The appeal of satellite IoT connectivity is its ability to provide global coverage with minimal terrestrial infrastructure, which is prone to damage or interference. In some cases, terrestrial network operators of NB-IoT and LTE-M are collaborating with Satellite Communications (SatCom) operators to enhance IoT connectivity. These partnerships are spurred by 3GPP Release 17’s introduction of two new satellite communication standards: NR Non-Terrestrial Network (NTN) and IoT-NTN. Satellite IoT is well-suited for use cases requiring expansive coverage, such as fleet management, connected agriculture,  condition-based monitoring, and asset tracking.

Geosynchronous Earth Orbit (GEO) and Low Earth Orbit (LEO) are the two primary satellite constellations used for the IoT. While GEO satellites achieve higher data throughputs than LEO satellites, they have higher latencies due to being positioned further away from the Earth’s surface (36,000 km away versus 250 km to 2,000 m away). LEO satellites, such as Starlink, are not only cheaper and more accessible, but they typically have lower latencies and enable Direct-to-Satellite (DTS) connectivity.

Pros

• Satellite IoT can potentially provide connectivity anywhere in the world.
• Satellite can provide IoT connectivity to dead zones that mobile operators often contend with.
• Terrestrial network equipment is almost never needed, reducing costs and complexity.
• LEO technology is advancing and is affordable.

Cons

• Satellite IoT is still a relatively new concept, often beaten out by established terrestrial technologies (cellular and LoRaWAN).
• The cost of entry is high, which hinders the competitive space for the satellite IoT market.
• Deploying a fleet of satellites can be expensive for satellite companies.
• Satellite networks typically lack indoor coverage, which is a huge disadvantage compared to other connectivity solutions.

Short-Range and Long-Range Connectivity Technologies Can Work Side-by-Side

While much of the narrative of this article assessed the competitive landscape of IoT connectivity technologies, there’s no reason why these solutions cannot be paired for a superior, hybrid offering. In fact, many industry analysts believe the combination of short-range and long-range connectivity technologies will be essential for enabling further IoT use cases in the future. As an example, SRW technologies like Wi-Fi and Bluetooth^® have dominated the smart home market to provide connectivity for smart thermostats, smart door locks, smart lighting, and other indoor-based IoT applications. When investing simultaneously in LPWANs, these smart home users can extend network coverage even further to outdoor areas, such as the garage, garden, and sidewalk. In other words, when used together, long-range network solutions can fill in the connectivity gaps left by SRW technologies.

A prominent example of this hybrid use case is Amazon Sidewalk, which aims to use Bluetooth^® and LoRa to connect smart home and smart city IoT devices in a community. This long-range deployment enables neighborhood-wide network coverage, allowing users to connect grills, pet trackers, home security cameras, door locks, and other IoT devices to the Internet. ABI Research forecasts that Amazon Sidewalk will eventually provide metro-area coverage, which will result in new IoT applications, notably tracking packages.

As this article pointed out, each IoT connectivity type has distinct advantages and disadvantages. Some solutions are clearly better suited for certain applications and use cases than others. However, the main takeaway is that industry experts tell ABI Research that short-range and long-range technologies should not be viewed as threats to one another. Instead, they should serve as complementary solutions to drive the IoT industry forward.

You can learn more about the leading wireless technologies connecting the IoT by downloading ABI Research’s Connecting the IoT: Wide-Area and Short-Range Wireless Technologies Market Analysis technology analysis report. This content is part of the company’s IoT Networks & Services Research Service.