Smart cows, comms and the IoT

As the IoT grows and mission-critical applications play a more dominant role, communications devices manufacturers will face pressure to ensure product reliability.

Internet of Things (IoT) devices fail every day. It’s a fact of life. If the failed product can be easily fixed or exchanged for one that works, the impact on a company’s brand and its bottom line may be minimal. When those IoT products are used in mission-critical applications and installed in hard-to-reach places or in harsh environments, all bets are off. These products simply can’t fail. When they do, a company’s success or failure may be on the line. Worse yet, if it’s an implanted medical device, someone could die.

Here’s the problem. Mission-critical IoT products designed in the lab under ideal test conditions don’t always perform as expected in the real world. There are many reasons why this is the case and it’s not always in the way one would think.

Real-world IoT example

Smart cows provide an excellent example of how a product designed in a lab can potentially fail in the real world. In a smart cow application, IoT sensors are surgically implanted in multiple locations under the cow’s skin and used to monitor the health of cows destined for the dinner table. Once in service, the sensors are expected to operate without fail for at least three years. During that time, they track the cow’s location, behaviour and other important factors such as temperature, which is a leading indicator of disease.

It sounds simple enough, but chances are the IoT sensors were never really designed to be implanted in cows. And, because the sensors are located inside the cow, they can’t be easily accessed if something goes wrong. The sheer weight of the cows and their habit of continually rubbing up against objects poses another problem. What happens when an adult cow, weighing upwards of 800 kg, decides to rub a part of its body where a sensor is located? Will the sensor get damaged? Will it migrate to another part of the cow’s body only to accidentally end up on someone’s dinner plate?

These are valid questions and point to a key differentiator between IoT devices that fail and those that succeed. Successful IoT products are intentionally designed not to fail — not just in the lab, but in the real world where many factors conspire to make them do just that.

Factors driving device failure

What are the factors that can make IoT devices fail in the real world? Here’s a look at the top five and some tips on how to navigate the potential pitfalls.

Factor 1: Congestion and load troubles. The moment a new IoT device is powered on, there may be hundreds of other IoT devices in its general vicinity. On one smart farm alone, there could be a herd of cattle (each with multiple implanted IoT sensors); sensors for measuring soil, plant and environmental variables; sensors for remote animal monitoring; farm bots and farm drones… not to mention any IoT devices the farmer might be carrying. The congestion may impede the device’s ability to operate normally. A dramatic rise in network traffic has a similar effect, forcing the IoT device to continually retransmit data. Its battery may drain quicker than expected, or it may fail altogether.

Solution: To avoid these failures, product makers should test the ability of their IoT devices to operate normally with a traffic load comparable to that expected in the target environment. That testing should also be done while simulating different traffic types like streaming video or voice.

Factor 2: Interference. Dense IoT device deployments, with many devices operating on the same crowded bands — for example, a large farm operation with smart cows — greatly increases the likelihood of interference between devices. Many of these devices can’t detect one another, let alone cooperatively share the airwaves, forcing some to behave in unexpected ways.

Solution: To avoid these issues, co-existence testing is essential. Co-existence testing helps product makers determine a device’s tolerance to other radio signals. It also helps ensure that a certain level of operation is possible, even in the presence of alternate radio protocols. IoT devices should also be challenged to see if they can cope with the many amplitudes, data rates and protocols they will likely encounter in the real world.

Factor 3: Roaming difficulties. Wireless IoT devices often roam from one location to another. That can be problematic if they haven’t been designed with robust roaming algorithms to minimise roam delay and avoid outages. An outage of just a few seconds can result in loss of valuable data. Congestion and interference have a dramatic impact on how well roaming algorithms work, making testing under real network conditions critical to preventing a device failure. Even in the smart farm scenario, implanting an IoT device in a cow only makes sense if that device can continually provide data that a farmer can access.

Solution: You can optimise roaming performance by testing IoT devices for roaming handoff behaviour in a variety of challenging conditions. Simulating the device’s antenna to ensure it can handle roaming, while coping with the volume and mix of traffic found in the real world, is also advisable.

Factor 4: Interoperability with network infrastructure. One day an IoT device may work as expected. The next day it may act erratically or stop working altogether. Chances are this isn’t a device issue, but rather the result of a firmware update on the network wireless access points. A slight change in the network infrastructure turns a perfectly working IoT device, like a sensor implanted in a cow, into one that’s not recognised by the target environment.

Solution: A protocol compliance test suite can provide an effective defence against this type of failure, assuming it tests against all defined functions of a device’s wireless protocol, and not just a small subset.

Factor 5: Security breaches. Any IoT device can be vulnerable to attack, even if it’s in a cow. Sometimes hackers are after data being collected. Other times, they are looking for a way to exploit the device’s lax security to gain a backdoor onto a network. That’s what can happen when a device is roaming and experiences interference. That interference can overwhelm the device and cause it to enter a fault state, resulting in long connection delays and making it temporarily vulnerable to hacking.

Solution: Stop hackers dead in their tracks by using a test suite with the ability to simulate roaming behaviour in a cluttered RF environment.

The path to success

As the IoT ecosystem grows and mission-critical applications begin to play a more dominant role, product makers will face increasing pressure to ensure their products are reliable.

For those companies looking to build mission-critical IoT products that won’t fail, the trick lies in thoroughly understanding a product’s deployment environment and performing the right type of testing to ensure it can withstand the factors conspiring to make it fail.

Whether those devices will be used for smart cows, in medical monitoring devices or something in between, those businesses choosing to make reliability a top priority are sure to set themselves on the right path to opportunity and success in the IoT.

White paper republished courtesy Keysight.

Image credit: ©stock.adobe.com/au/kinwun