Don’t crowd the cloud – Narrowband IoT

April 19, 2016 // By EDN Europe
Tim Bonnett, Director, Alpha Micro Components
The original end-to-end infrastructure for IoT rigidly defined the chain as Sensor (end-point) > Gateway > Cloud. Essentially feudalistic, with a single ‘cloud’ servicing multiple gateways, each providing cloud access to innumerable sensor devices via short range RF technologies. This methodology is perfectly suited where we deploy technology to complement existing technology, in our homes or factories, however there are new use cases demanding deployment well away from any fixed broadband connection our gateway can connect to, sometimes even outside of traditional 3G/4G coverage altogether. What then?

Narrowband IoT (NB-IoT) promises to negate the need for an intermediary gateway and allow devices to connect directly to the cloud, even in the very remotest areas. Whilst existing cellular networks provide the infrastructure, they’re currently optimized for smart phones that demand frequent transmission and high bandwidth, NB-IoT demands the opposite. NB-IoT trades the high bandwidth unnecessary for transmitting small amounts of infrequent data for increased coverage, which facilitates ultra-low power end-point devices and can even penetrate deep underground. This isn’t just about increasing coverage, halving required bandwidth doubles the number of available connections and typical IoT devices require 10 -3 of that bandwidth, facilitating the predicted inundation of IoT devices anticipated. At device level, NB-IoT reduces BOM cost, vastly increases deployment area and introduces power saving capabilities which permits battery lives of several years.

One’s natural reaction to this new technology is to consider the very remotest place one can and it’s true that these are the extremes that NB-IoT can, and will, service. Gas and water meters often demand deployment in remote rural areas or deep underground, so the ability to transmit metering data directly to the cloud is an obvious use case for NB-IoT, but what else? Remember, existing cellular networks demand too much power and just because there’s a fixed broadband connection nearby doesn’t mean you can, or would want to, connect your assets via it.

Figure 1: NB-IoT transmits data directly to the cloud

Our cities provide the highest concentration of fixed broadband connections and the best cellular coverage, but neither offer suitability for new use cases made possible by NB-IoT. Smart cities simplistically demand asset control and monitoring, where those assets may themselves be mobile, plus security, reliability or both demands authorities can always connect directly. Local authorities are already deploying smart street lighting, whilst developing solutions to identify free parking spaces and automatically determine optimal waste bin collection routes - all designed to reduce a city’s carbon footprint.

Figure 2: NB-IoT waste management solution demo (Image courtesy of u-blox)

Consumers are well acquainted with the limitations of today’s wearables, which invariably demand tethering to the very devices they’d ideally remove the need for one to carry around. NB-IoT will give those wearables their own long-range connectivity and open doors for new use cases where running smart phone hotspots simply isn’t viable. GPS derived tracking of commercial livestock and protected wildlife can offer instant alerts of irregular behavior or breaching a pre-defined containment zone. For responsible parents, wearable wrist straps that track their movements will enable their children to enjoy a freedom taken for granted by previous generations and sadly often curtailed in today’s culture of a perceived high risk to their safety.

In our factories, internet access is now ubiquitous but often unsuitable for new use cases across building automation, security and asset control. Instant reporting of building maintenance issues is too critical to rely on a single local broadband connection and naturally security issues exist when a factory’s internal network becoming compromised would relinquish control of the entire building to a malicious party.