1. White Paper
May-2013
‘Sentrollers’ and ‘The Internet of Things’
By: Cees Links, Founder and CEO
GreenPeak Technologies – www.greenpeak.com
The new buzzword floating around the world is the ‘Internet of Things’, almost positioning the current
Internet as already something from the past. What exactly is the Internet of Things and how will it affect
your business? And what are “sentrollers”? Let’s take a closer look and try to understand the drivers of
this new development in communication and networking and what this means for the Internet as we
know it today.
The Changing Internet
The current Internet, known as the “Internet of People”, has become a huge success since it really
accelerated in the 90’s of the last century. Moreover, the current young generation is struggling to
recognize that there was “life before the Internet”. Sharing information, distributing content in a way
that is upsetting industries (i.e. YouTube replacing TV) and creating new paradigms for communicating
(i.e. Skype, Twitter) and working together (integrated end-to-end logistical systems), there is no doubt
that the Internet has had a profound effect on our lives.
© GreenPeak Technologies 2013 – IoT & Sentrollers White Paper
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2. The Internet has evolved to be the essential information sharing medium and communication backbone
of our society – from metropolitan citizens to jungle residents and farmers in the countryside.
However, the Internet as we know it today is just a beginning, because more and more equipment is
getting connected over and through the Internet. Today most of the (end) nodes on the Internet are
people, using (smart) phones, tablets, laptops and computers. But this is changing: equipment and
devices – machines – connected to the Internet (e.g. set-top boxes, cameras, cars) are starting to shift
the balance away from people towards things. The future is clearly moving into a direction where the
number of things connected to the Internet will overwhelm the number of connected people.
Predictions range up to a factor of 100 to 1 or more: the Internet of People will transform into the
Internet of Things.
Sentrollers: Sensors, Actuators and Controllers
There is another significant change happening at the same time.
The current Internet is really about content sharing and distribution: high data rates and large amounts
of data are driving the IT industry (from Gigabits/second to Terabytes), sparking new and exciting
developments in “cloud” data storing and analysis.
Many of the new devices connected to the Internet of Things will be different: these devices are usually
sensors, controllers, actuators or combinations, going by the convenient all-encompassing term of
“Sentroller”. For instance: a thermostat senses the temperature, compares this with a desired
temperature and activates a heater or air conditioner, controlling, essentially “sentrolling”, the
temperature.
In practice sentrollers absorb and/or produce very limited amounts of information, but connectivity to
the internet is essential. The Internet of Things will host the applications that know how to interpret the
information provided by sentrollers and what action to be taken. The “smarts” of the Smart Home,
Smart Energy, Smart Buildings, etc. actually reside in the cloud. The sentrollers are the end-nodes that
will become the majority population of this Internet of Things.
One sort of mini example of this 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 pressure, etc.) and controllers (from the steering wheel itself to little
servos to adjust chairs and mirrors, etc.). The reason for all this automation is obvious: the driver must
be able to understand, handle and control everything, while concentrating on safely driving on the road.
The Internet of Things is replicating this concept on a much larger scale.
© GreenPeak Technologies 2013 – IoT & Sentrollers White Paper
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3. The Smart Home
The starting point of the Internet of Things is clearly the Smart Home. In a way the digital car is a precursor of the Smart Home. In the Smart Home however, we are not sitting constantly in the same chair:
we will have access to many sentrollers from different locations.
In our home we already see many ‘sentrollers’ in many places. Just looking around we can find
thermostats, security control panels with motion sensors, our utility meters (electricity, gas, water), we
have (many!) remote controls laying around the coffee table and everywhere else, and think about sun
shades, lights and light switches, door locks, etc. In a way these are all sentrollers around the house. We
probably can go on-and-on. Unfortunately today these are all “generation-zero” sentrollers: sometimes
largely mechanical, and in most situations, stand-alone.
In the real Smart Home all the devices are connected with the Internet. The role of these devices is also
not tied to a single application. Because the devices are connected to the Internet they can play
different roles under different circumstances. An example of this is a motion sensor in a room. In a
normal condition a motion sensor will turn on the lights and the heating if someone is detected in the
room. However, if the house-alarm is switched on, the motion sensor actually triggers an alarm if the
motion sensor is detecting 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.
Utilities and Service Providers
How will these sentrollers in the home become part of the Internet of Things? The main drivers are the
utilities and the MSO’s (the Multi-Service Operators), who see their current four mainstream business
(telephone, TV/radio, internet and cellular) under pressure and who are looking to offer new services to
their subscribers. Their new so-called “fifth play” offerings include home security, energy management,
home care, and many others. The fifth play also includes devices that connect to the smart meter, the
set-top box or the home gateway, and from there on to the internet enabling users to control their
equipment and their energy bill with their smart phone.
Looking at an average household today, people may be connected with between 5 and 10 devices
(computers, laptops, smart phones, TV’s) to the internet. In the next few years, this number will be
easily dwarfed when maybe 100 sentrollers per household are getting connected to the Internet: the
Internet of Things.
© GreenPeak Technologies 2013 – IoT & Sentrollers White Paper
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4. The Internet of Things
Some interesting observations can be made regarding how the Internet of Things will change the
internet as we know it. In the first place the stellar increase in the number of nodes will require an
increase of the number of internet addresses available (each “thing” on the Internet of Things needs a
unique identification number). This problem that has already been addressed by the IETF through the
introduction of IPv6, succeeding IPv4.
The other observation is that the Internet of Things will not likely (and definitely not initially) create a lot
of additional network traffic. People have a tendency to produce or absorb a lot of data (e.g. a video, the
“higher definition” the better!), but in comparison sentrollers are relatively minimal in data production
or consumption (bits instead of Terabytes).
This means that building the Internet of Things does not require a lot of extra work on the infrastructure of the internet: with the new IPv6 addressing scheme the current infra-structure is capable of
handling the Internet of Things on top of the Internet of People. People may ask themselves however,
whether the growing dependency on the Internet not only for content, but also for sentrollers, is going
to put higher demands on the security and reliability of the Internet. Definitely more work needs to be
done to avoid the growing critical dependency on the Internet that could cause massive disruption of
the society.
ZigBee
The next interesting question about the internet of Things is: how will it be built up, and what role will
existing wired, and in particular wireless technologies be playing. The most challenging part is how to
get a device “on the network” (on the internet): the access technology itself. What technologies and
service models are required to enable cost effective connectivity? And do devices need roaming, that is,
do they move around while staying connected to the Internet. In this last respect it is probably good to
notice that “Things” by nature are more static than “People”, so roaming may be less of a requirement.
At the same time cost is a serious requirement: the cost of “connecting” a Thing may quickly outpace
the cost of the thing itself.
In this respect it is also interesting to notice that the requirement for high data rate is replaced by the
requirement for a long battery life. For instance most of the WiFi devices today are connected to the
mains power, and if not, say with a laptop or a smart phone, everyone has his own regular routine to
make sure the batteries of the devices are regularly charged.
The world of sentrollers however is different. Connecting sentrollers to the mains power can be
cumbersome: expensive wiring, expert installation. But 100 devices in your home with a battery life of
one year means that you have to change on average two batteries every week – worse: every week
there are two sensors that stopped functioning and need attention. So, for sentrollers, the data rate is
of low priority compared to the device’s energy consumption. This means that the battery life of the
device preferably should exceed its life!
© GreenPeak Technologies 2013 – IoT & Sentrollers White Paper
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5. ZigBee is an open standard like WiFi that describes the protocols for data-communication of sentrollers
in the 2.4 GHz worldwide – one frequency band worldwide. The ZigBee name is owned by the ZigBee
Alliance, an industry group with more than 400 members, including most of the large semiconductor
companies, who make chips for building products that will be connected to the Internet of Things. The
ZigBee standard describes the radio protocols (based on IEEE 802.15.4) as well as the network layers and
application profiles. This makes it possible for devices of different vendors to interoperate in a way as
expected by the end-user.
ZigBee has not been introduced with the same fanfare with which Apple introduced WiFi and gave the
acceleration of the Internet of People a major boost with the Apple Airport, the first home router/access
point in the industry. But the reality is that many utilities and large operators worldwide, led by Comcast
in the USA and their Xfinity program, are equipping their set-top boxes and gateways today with ZigBee,
effectively building a corner stone for the Internet of Things in every home.
For the cable operators, one financial justification comes from the standardization of remote controls
(replacing infra-red with radio technology) thereby reducing service calls. But considering the fact that a
remote control essentially is a ‘sentroller’, it effectively implements the Internet of Things already in a
cost effective way, preparing for the roll-out of new smart home services, like security, energy
management and home care.
© GreenPeak Technologies 2013 – IoT & Sentrollers White Paper
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6. Comparing
This may be a good point to summarize comparing the Internet of People with the Internet of Things.
Internet of People
Internet of Things
Computers:
Sentrollers:
smart phones, tablets, laptops,
computers, TV’s, game consoles, etc.
smart meters, thermostats, motion
sensors, remote controls, etc.
Content sharing and distribution
Sense and controls
High data rate
Long battery life
Dynamic roaming
Static (roaming)
Outdoor/on the road
GSM/3G/LTE
Neul
At home/in the office
WiFi (IEEE 802.11)
ZigBee (IEEE 802.15.4)
Average 5-10 units per household
and growing
Emerging, growing 100 units per
household and beyond
Devices
Characteristics
Main Function
Key Requirement
Roaming
Access Technologies
Volume
However, putting the two Internet’s side-by-side does not mean that there will be two Internet’s. The
existing Internet of People will easily absorb the Internet of Things with the existing infrastructure, once
the transition to IPv6 is completed.
Beyond the Smart Home
As mentioned the Internet of Things starts at the Smart Home, driven by utilities and MSO’s 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, maybe not directly connected to the Internet of Things, but that will be just a
small step further. Beyond the Smart Buildings there are already many ideas floating around about
Smart Cities. One interesting example of a simple, but effective application: 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. All that is required is a motion sensor in a street lamp and an
effective standard infra-structure that interprets the data that comes in.
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7. Also industries, logistics, agriculture, etc. 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,
populating the Internet of Things.
Summarizing
It is clear that the Internet of Things is starting with consumers – in the house – implementing the Smart
Home. The wireless access technology for the Smart Home is ZigBee, the open worldwide IEEE standard,
equivalent to WiFi. Where WiFi stands for reliable high data rate connectivity, ZigBee stands for a long
battery life. In the same way as WiFi today is synonymous for wireless Internet of People, ZigBee is
becoming synonymous for the wireless Internet of Things, making it possible for “any-Thing” to
seamlessly connect to the internet any place, any time and without worries about power or battery life.
The Internet of Things will further enable new services that will make our lives safer and more secure,
more convenient and comfortable. The Internet of Things will also help to manage our costs, in
particular regarding energy consumption, as it allows us to reach out to any device in our home from
any place in the world. In this way the arrival of the Internet of Things will fuel a new industry of devices
and services that will rapidly outgrow the current Internet of People and our dependency on
interconnectivity will grow even stronger.
www.greenpeak.com
© GreenPeak Technologies 2013 – IoT & Sentrollers White Paper
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