A communications technology that promises lower bandwidth and higher latency seems an unlikely proposition in an age when the demands for speed and capacity are rising inexorably. However, low-power wide area networks (LPWANs) are set to play an important role in expanding the possibilities for the Internet of Things (IoT) in cities, buildings, and utility networks. LPWANs are targeted at applications that have low or infrequent data throughputs but which benefit from low-cost modems (less than $5), cheap connectivity (a service cost of a few dollars per year), long-range access, deep penetration, and an extended battery life for devices (around 10 years on a standard battery).
LPWANs come in a number of flavors. In February of this year, the LoRa Alliance was launched by a group of technology suppliers and telecoms operators that support the LoRaWAN specification by developed semiconductor company, Semtech. Initial supporters of the Alliance include Cisco, IBM, Sagemcom, and Semtech, alongside telecoms such as Bouygues Telecom, KPN, SingTel, and Swisscom. One of the first project announcements is partnership between French IoT supplier Actility and Swisscom to deploy a LPWAN around the cities of Geneva and Zurich.
Other players in the LPWAN space are focusing on the evolution of 4G LTE standards that will enable low-cost, low-power communications to support machine-to-machine applications. Several telecoms and equipment providers have announced what is referred to as LTE-M projects, including Nokia and Korea Telcom. Vodafone has also announced its own low-power IoT service, dubbed the Cellular Internet of Things, which it has developed in partnership with Huawei.
Another significant LWPAN initiative comes from French communications company SIGFOX, which is working globally with network system operators to deploy LWPANs using its ultra-narrowband technology. In the United Kingdom, for example, Arqiva is rolling out a SIGFOX-compatible network to 10 cities initially.
Do the Pros Outweigh the Cons?
LWPANs offer the prospect of sensors and other intelligent devices being able to connect instantly into a communications network at a cost of a few dollars a year. LPWANs are suitable for applications where high bandwidth and low latency are less important. LPWANs are not suited, for example, to applications requiring high bandwidth (such as video streaming), low latency, or the continuous tracking of moving objects. LPWANs are largely complementary to existing network technologies, but may present competition to radio frequency (RF) mesh technologies for applications such as smart street lighting and smart parking, and even some forms of smart metering.
LPWANs allow for low-cost piloting and easy scaling of innovative applications. A supplier developing a smart city solution, for example, could quickly demonstrate the benefits of an application for air quality monitoring. Similarly, a utility could use a sensor connected to a LPWAN to monitor assets that lack local power (such as gas and water pipelines) or where the business case does not justify a more expensive solution. A facility manager could use LPWANs to fill gaps in their existing building management system or to retrofit sensors to older buildings.
The LPWAN market is in the innovation phase, where an explosion of different approaches is to be expected and indeed welcomed. However, multiple versions and standards are likely to confuse potential adopters, and industry players need to push ahead on the development of open standards and interoperability models. Over the longer term we will see a growing focus on the so-called HetNet environments in cities, which will allow seamless integration across network protocols depending on location and requirement. In the meantime, low-power networks can be an important accelerator for smart cities and other IoT markets.