The Internet of Things has become a force we can’t ignore. In fact, Gartner forecasts that 6.4 billion connected things will be in use worldwide in 2016, up 30 percent from 2015, and will reach 20.8 billion by 2020.
Since a lot of these devices run on batteries, transmit small chunks of data infrequently, and, in the case of smart city/safe city projects, are deployed over a long distance, a connectivity scheme is needed to ensure power efficiency and quality of transmission. Currently, two dominant wireless connectivity options are Wi-Fi, which does not have a long range and consumes a lot of power, and cellular (3G/4G), which is costly. It’s against this backdrop that Semtech developed the LoRa technology, which uses anywhere between 70MHz and 1GHz portions of the radio spectrum and transmits data from 300 bps up to 50 kbps over variable distances of up to 40 kilometers. This modulation technique has significant advantages – including lower cost, good penetration of obstacles, greater coverage over longer distances, and better battery life – when compared with cellular networks and Wi-Fi.
To ensure successful LoRa deployments, IBM, in partnership with Semtech, developed the long-range signaling and control (LRSC) software. “It aims to operate efficiently and securely a large scale network of devices operating according to the LoRaWAN 1.0 standard. We started development of this system around 2013 in parallel with the design of the LoRaWAN standard which we co-authored: We strongly believed that LoRa by Semtech is a very good long-distance radio technology," said Michael Baentsch, Embedded IoT Security scientist at IBM Research Zurich.
A typical LRSC installation comprises a central network server linking hundreds or thousands of radio gateways to dozens of application routers. In this way, hundreds of thousands of LoRaWAN 1.0 end devices, from smoke detectors, temperature sensors, to smart electrical heating controllers, can establish a secure bidirectional, low-data-rate connection with corresponding apps, thus enabling millions of small, IoT-type transactions per day per system installation.
Among cities that have deployed smart/safe city initiatives using the LRSC solution are New York and the Swiss City of St. Gallen. However, Baentsch stated that the solution isn’t just for smart/safe city projects alone. U.S.-based networking solutions provider Senet, for example, has used the technology to help clients monitor fuel and heating oil usage via a network of sensors attached to customers’ fuel tanks.
“The LRSC system is special in that it has never been geared to one particular use case: It always tried to be as generic as possible,” he said. “At the same time, we have proven by field trials as well as synthetic lab tests that the LRSC system can handle significant loads. This has proven to be correct by several installations of LRSC around the world, the most significant in size being the one by Senet.”
LRSC also seeks to ensure the security of transmission. In line with the LoRaWAN specification, the system uses cryptographic authentication and end-to-end encryption with device-specific AES128 keys. More notably, the technology clearly separates the network operator from the users of the network. “Security and multi-tenancy are the typical problems often only considered in hindsight. With LRSC we gave these topics priority in the design of the solution,” Baentsch said.