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“Sentrollers” Will Play A Role In The Internet of Things

“Sentrollers” Will Play A Role In The Internet of Things

The Internet of Things will depend on "sentrollers," or sensors that measure data and then have the intelligence to take action based on what's reported. 

The current internet can be considered the “Internet of People,” connecting users worldwide in a diverse variety of ways. Over the last decade it has evolved into the essential information-sharing medium and communication backbone of our society, from metropolitan citizens to farmers in the countryside.

Most of the (end) nodes on the Internet are people, using smart phones, tablets, laptops, and desktops. But this is changing. Equipment and devices connected via the Internet to each other are starting to shift the balance away from connecting people towards connecting things—hence, the Internet of Things.

The future is clearly moving to where the number of things connected to the Internet will overwhelm the number of connected people. Predictions range up to a factor of 100 things or more to one person. The Internet of People will transform into the Internet of Things.

Sentrollers: Sensors, Actuators, And Controllers

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Currently, the Internet is mostly about content sharing and distribution. High data rates and large amounts of data are driving the IT industry from gigabits/second to terabytes, generating new and exciting developments in “cloud” data storing and analysis.

However, many of the new devices connecting to the net will be sensors, controllers, and device actuators. Instead of megabits of data, they only will need to send a few bits such as an on or off message every few minutes or hours and remain “sleeping” most of the time.

These low-data-rate devices can be called sentrollers, creating a connected home ecosystem. For instance, a thermostat senses the temperature, compares it with a desired temperature, and activates a heater or air conditioner, controlling (or essentially “sentrolling”) the temperature.

The Internet of Things also can host the applications that know how to interpret the information provided by sentrollers and decide what action will be taken. The “smarts” of the smart home, smart energy, and smart buildings can reside in the cloud as well as in a local controller in the home. The sentrollers are the end nodes that will become the majority population of this Internet of Things.

One interesting example is today’s sophisticated digital automobile. From behind the steering wheel, almost everything in the car can be checked (“sensed”) and controlled. The car is filled with sensors (for temperature, oil level, tire pressure, etc.) and controllers (from the steering wheel itself to little servos to adjust chairs and mirrors). The reason for all this automation is obvious. The driver must be able to understand, handle, and control everything while concentrating on safely driving. The Internet of Things is replicating this concept on a much larger scale.

The driving force for the Internet of Things will be the smart home. In a way, the digital car is a pre-cursor of the smart home. In the smart home, however, we are not sitting in the same chair. Instead we will have access to our home’s many sentrollers from different locations: on the road, in a hotel room, on the beach, or even next to the pool in the back yard.

Many sentrollers already exist in our homes, like thermostats, security control panels with motion sensors, and utility meters (electricity, gas, water). We even have (many!) remote controls around the coffee table and everywhere else. Devices such as sun shades, lights and light switches, and door locks all are part of the sentroller ecosystem. Unfortunately today, they’re all “generation-zero” sentrollers—sometimes largely mechanical and, in most situations, standalone.

In the real smart home, all the devices are connected to the Internet via some sort of home controller box with a Web connection. These devices can connect via wires or Wi-Fi. Many of the sensors, especially those that operate on batteries or energy harvesting, will wirelessly connect via ZigBee.

That’s the “connected” home. It’s “smart” because these devices aren’t necessarily tied to a single application. They’re connected to the Internet, so they can play different roles under different circumstances. For example, a motion sensor can turn on the lights and the heating if it detects someone in a room. But if the house alarm is switched on, the motion sensor will trigger it if it detects someone. This is when we really can start talking about a smart home. The sentroller is disconnected from a specific application and connected to a “smart” application running in the cloud of the Internet of Things.

Too Much Data For The Pipes?

How will the Internet of Things change the Internet as we know it? In the first place, the explosive increase in the number of nodes will require an increase in the number of Internet addresses available since each “thing” needs a unique identification number. The Internet Engineering Task Force (IETF) already has addressed this problem through the introduction of IPv6, succeeding IPv4, providing an almost limitless number of possible Web addresses.

Second, the Internet of Things likely will not create a lot of additional network traffic. People have a tendency to produce or absorb a lot of data. With video, for instance, the higher the definition, the better! But in comparison, sentrollers are relatively minimal in data production or consumption, managing bits instead of terabytes. This means that building the Internet of Things doesn’t require a lot of extra work on the Internet’s infrastructure. With the new IPv6 addressing scheme, the current infrastructure can handle the Internet of Things on top of the Internet of People.

However, people may ask whether the growing dependency on the Internet not only for content, but also for sentrollers, is going to put higher demands on security and reliability. This is a valid concern. Security must improve. More work needs to be done to avoid the growing critical dependency on the Internet that could massively disrupt society.

Beyond The Smart Home

The Internet of Things is starting at the smart home, driven by utilities and multi-service operators, and it will not stop there. The logical next step is from the smart home to smart buildings, and a lot is already happening in this space. Beyond the smart buildings, many ideas about smart cities already are floating around.

For example, why should a street light burn when there is no traffic? With the increasing pressure to conserve energy, this application can be a small but very effective contribution. It only requires a motion sensor in a street lamp and an effective standard infrastructure that interprets the data that comes in. Why waste energy when there is no need?

Also, industries, logistics, agriculture, and other areas will benefit from the wave of sentrollers that is currently rolling out for the smart home and will multiply the number of devices that get connected to the Internet, further populating the Internet of Things. It might take another decade, but the world, our buildings, and our homes soon will be a lot smarter and we will have a lot more control over our environments.

Cees Links is the founder and CEO of GreenPeak. Under his responsibility, the first wireless LANs were developed, ultimately becoming household technology integrated into PCs and notebooks. He also pioneered the development of access points, home networking routers, and hotspot basestations. He was involved in the establishment of the IEEE 802.11 standardization committee and the Wi-Fi Alliance. And, he was instrumental in establishing the IEEE 802.15 standardization committee to become the basis for the ZigBee sense and control networking.

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