Rising data costs endanger IoT deployment

As emphasised by Cisco's forecast of 50 billion devices and objects connected to the Internet by 2020, the extensive roll-out of Internet of Things (IoT) devices is now facing major concerns. As the dream morphs toward reality, IoT system designers ponder a number of yet-to-be-sorted-out deployment challenges. These include cost [of IoT devices], limited battery life, a bandwidth-constrained network, the lack of standard protocols and a security shortfall.

But what about the cost of data? IoT is all about connected devices designed to gather data for intelligent analysis.

Given that 50 billion IoT devices and their contents need to live for a long time, the cost of data—associated with the transmission, storage and mechanisms for efficiently retrieving it—can't be ignored, stated Tom Hunt, president and CEO of WindSpring.

WindSpring is a software technology licensing company with hopes to enable cost-effective solutions for IoT deployments by licensing a suite of IoT tools—such as data compression and protocol conversions—to device vendors and service providers.

Figure 1: Cisco's forecast of 50 billion devices and objects connected to the Internet by 2020 (Source: Cisco)

Noting that IoT has so many uses, Lee Doyle, principal analyst at Doyle Research, said the amount of IoT data generated is accumulating quickly. Further, IoT devices need to operate under varying situations—including constrained network bandwidth and latency. "You need IoT compression tools like what WindSpring is proposing."

Spiraling out of control

Many IoT device developers and service providers don't realise until much too late in the design cycle that their data costs are "quickly spiraling out of control," Hunt observed.

IoT devices generate frequent bursty messages. When sent via traditional cellular network such as 4G/LTE, data gets expensive, said Hunt.

Assume that you have a wearable device that sends out data in 166 bytes. Once it's sent via IP network, the data balloons to 403 bytes (including the HTTP header in 237 bytes). The longer it takes to send a message and the chattier its protocol gets, "it costs you more," explained Hunt. Additional effects are radio usage and battery life.

Some cellular network operators are turning to Low-Power Wide-Area Networks (LPWANs) such as Sigfox and LoRa, said Hunt. They're looking at ways to dump IoT data traffic onto those separate networks.

But LPWANs are designed to run at extremely low data rates. Restrictions imposed by Sigfox, for example, are a 12-byte payload for uplink and 140 messages per day per device. Lora sets two-way communication at 0.3kbit/s to 50kbit/s data rate, with maximum payload at 256 bytes. This, in turn, requires longer air time.

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