These IoT networks are 'unapologetically slow'
While the International CES this week emphasized home networks and LTE-equipped cars, a different kind of network that can send tiny messages across a city crept toward a future that some people think may be huge.
The concept is low-power, wide-area networks (LPWANs), which make up for extremely low data rates by going farther than a cellular signal and working in tiny devices that can last months on a small battery. They won’t carry TV shows or virtual reality games, but they may help to grease the wheels of global commerce and government. Some wearables may get in on the act, too.
LPWAN is designed primarily for M2M (machine-to-machine) networking, which is already widely used for things like tracking assets, monitoring industrial equipment and collecting data from smart meters. While a lot of those tasks are handled by cellular radios today, LPWAN will be the dominant form of wide-area wireless for M2M by 2022, according to Jim Morrish, chief research officer at Machina Research.
Like most new networking technologies, LPWAN comes in lots of different forms and hasn’t settled into a standard groove that everyone agrees on. At CES, companies backing one variant announced they had formed a new group, the LoRa Alliance, to standardize LPWAN. But it could be a long time before that approach or any other emerges as a clear winner. That’s a familiar refrain in the Internet of Things these days.
“I expect that the overall IoT networking space will remain very confused for several years, and at least 10 different networking technologies will gain significant traction for IoT applications,” Gartner analyst Nick Jones said via email. Long-range IoT networks are even more immature than other parts of that unsettled industry, he wrote. “I see the market in what you might call a land-grab phase. Everyone is trying to get ahead to establish their presence.”
LPWANs solve the problem of how to reach large numbers of connected devices without having to saddle them with relatively large and energy-hungry cellular radios. Those devices, such as sensors, smart meters and location trackers, may have to stay on for months or years but don’t have room for bulky batteries.
Fortunately, they don’t need cellular speed, either, just enough capacity to send small amounts of data. LPWAN speeds may be measured in the hundreds of bits per second or less. The networks primarily use unlicensed frequencies, such as the 900MHz band in the U.S., so they can coexist with cellular networks. They may also be used as backup for cellular to keep devices connected where broadband can’t reach.
One advantage of the low data rates on LPWANs is that they don’t require as many base stations as cell networks do. With that factor and unlicensed frequencies, the cost of connecting can be dramatically lower. Enterprises buying connectivity for many devices may pay as little as $1 per connection, per year.
The LoRa Alliance will promote the LoRaWAN protocol as the foundation for wide-area networks around the world, allowing users to count on connectivity wherever they take devices or equipment. LoRaWAN is based on patented technology from Semtech, a semiconductor company in San Jose, California, which is open to licensing it to other chip makers. It already has a licensing deal with Microchip Technology, said Hardy Schmidbauer, wireless products director at Semtech. He declined to comment on whether those chip makers need to pay for the license.
LoRaWAN is already a complete technology and is in commercial use in numerous deployments, primarily private networks such as smart utility meter systems, Schmidbauer said. The Alliance plans to help promote its use in public networks, including ones run by carriers, where many customers can buy service.
Other members of the Alliance include IBM, Cisco Systems, and other IoT vendors, as well as telecommunications carriers including SingTel, KPN of the Netherlands, and Swisscom. IBM says it has released its software for LoRaWAN as open source under the Eclipse Public License.
LoRaWAN is one among several LPWAN platforms in development or use, including Weightless, RPMA (Random Phase Multiple Access) from On-Ramp Wireless, and a system being deployed by French technology and service provider Sigfox.
Sigfox has already built a nationwide LPWAN in France by itself and deployed one across Spain with a carrier partner that provided cell sites and other infrastructure. It’s building out a network in the U.K. with another partner. In March, Sigfox plans to announce the completion of a network across the San Francisco Bay Area, and it aims to be in the top 20 markets in the U.S. this year.
Several silicon vendors, including Texas Instruments and STMicroelectronics, use Sigfox technology free of charge in chips for devices, said Luke D’Arcy, director of business development for Sigfox in the U.S. The company is working with the 3GPP, which develops most cellular technologies, to standardize its technology. It hopes ultimately to make the system part of the 5G specification expected around 2020. Ultimately, Sigfox wants to be just one of many companies deploying and operating Sigfox-based networks, D’Arcy said.
Sigfox’s networks run at about 100 bits per second in Europe and will offer up to 500 bits per second in the U.S.
“We’re unapologetically slow,” D’Arcy said. “It would be compellingly frustrating to use to surf the Internet. We’re absolutely not going after connecting up human beings.”