The four principle LPWA connectivity techologies for IoT deployments
The internet of things (IoT) is gathering momentum in the enterprise space. Analyst firm Machina Research anticipates there will be three billion low-power wide-area (LPWA) connections by 2025, and Analysys Mason forecasts LPWA technologies will generate $5 billion globally in connectivity revenue by 2025. And yet the market does not appear to have settled yet on a dominant connectivity standard, with traditional mobile operators pulling in one direction, and an alternative breed of LPWA technologies operating in unlicensed spectrum.
Here, we offer a recap of the four principle options for IoT connectivity.
Narrowband IoT (NB-IoT), defined by the mobile network operator association the GSMA, is a standards-based LPWA that significantly improves the power consumption of user devices, system capacity and spectrum efficiency, especially in deep coverage. Battery life of more than 10 years can be supported for a wide range of use cases.
It is supported by the majority of mobile equipment, chipset and module manufacturers, and can co-exist with 2G, 3G, and 4G mobile networks. It also benefits from all the security and privacy features of mobile networks, such as support for user identity confidentiality, entity authentication, confidentiality, data integrity, and mobile equipment identification.
One of the main deployers of NB-IoT is Vodafone. At the beginning of 2017, it launched the network commercially to meet demand from its customers in Spain. It has tested devices from Neul and Qualcomm against Huawei, Ericsson and Nokia systems in multiple regions, all of which have been successfully interconnected with Vodafone’s core IoT network.
In June 2018, mobile operators Deutsche Telekom and Vodafone Group successfully completed the first international roaming trial in Europe using licensed NB-IoT technology. The roaming test cases included important power saving features such as Power Saving Mode (PSM), Long Periodic Tracking Area Update (TAU) and various throughput and round-trip-time measurements.
Long Term Evolution for Machines (LTE-M) is another GSMA-backed LPWA network, which carries the same benefits as NB-IoT. However, it provides low evice complexity and extended coverage, while allowing the reuse of existing LTE base stations.
The main differences between the two LPWAs are latency and speed, which mean each network is suited for different applications of IoT. For example, according to Sierra Wireless, for mission-critical applications, LTE-M is the only option as it supports devices that need to communicate in real time. Some examples of real-time communication include voice, emergency data and precision tracking data. The company also pointed out that while LTE-M can cover NB-IoT applications also, NB-IoT is designed for simpler static sensor type applications.
AT&T, KPN, Orange, Telefónica, Telstra and Verizon are among the operators rolling out LTE-M, following pilots of the technology across a wide variety of use cases, including monitoring individuals’ location and vital signs using wearable devices. AT&T and its enterprise customers have also piloted LTE-M for smart shelving, asset management, logistics, fleet management and other use cases that require low-cost mobile connectivity.
The LoRaWAN specification is an LPWA networking protocol designed to wirelessly connect battery operated ‘things’ to the internet in regional, national or global networks, and targets key IoT requirements such as bi-directional communication, end-to-end security, mobility and localisation services. Unlike GSMA-backed LPWAs, LoRAWAN doesn’t use licenced spectrum.
According to ABI Research, LoRaWAN saw a 54% YOY growth, which was mostly attributed to its increased popularity in China. It is thought that 40 Chinese cities alone had deployed LoRa for applications such as smart meters, parking sensors and air quality sensors.
The LoRaWAN specification is developed and maintained by the LoRa Alliance: an open association of collaborating members, which is backed by more than 500 members.
LoRa’s competitor, Sigfox, is considered the first global IoT network where objects are not attached to the network.
Offering a software-based communication solution, where everything is managed in the Cloud rather than the device, it is thought that it reduces energy consumption and silicon costs. It also collects data from sensors and devices with a single, standards-based set of APIs, and is considered complementary to traditional cellular M2M.
According to ABI Research, Sigfox had the largest share of public LPWA connections worldwide, mainly in Europe. Private LPWA networks accounted for 93 per cent of its connections in 2017. With a presence in 60 countries, Sigfox currently lists 51 operators supporting its global IoT network.