12-10-2016, 02:49 PM
[attachment=72932]
Abstract—Many technical communities are vigorously
pursuing research topics that contribute to the Internet of Things
(IoT). Today, as sensing, actuation, communication, and control
become ever more sophisticated and ubiquitous, there is
significant overlap in these communities, sometimes from slightly
different perspectives. More cooperation between communities is
encouraged. To provide a basis for discussing open research
problems in IoT, a vision for how IoT could change the world in
the distant future is first presented. Then, eight key research
topics are enumerated and research problems within those topics
are discussed.
INTRODUCTION
mart devices. Smartphones. Smart cars. Smart homes.
Smart cities. A smart world. These notions have been
espoused for many years. Achieving these goals has been
investigated, to date, by many diverse and often disjoint
research communities. Five such prominent research
communities are: Internet of Things (IoT), Mobile Computing
(MC), Pervasive Computing (PC), Wireless Sensor Networks
(WSN), and most recently, Cyber Physical Systems (CPS).
However, as technology and solutions progress in each of
these fields there is an increasing overlap and merger of
principles and research questions. Narrow definitions of each
of these fields are no longer appropriate. Further, research in
IoT, PC, MC, WSN and CPS often relies on underlying
technologies such as real-time computing, machine learning,
security, privacy, signal processing, big data, and others.
Consequently, the smart vision of the world involves much of
computer science, computer engineering, and electrical
engineering. Greater interactions among these communities
will speed progress.
In this paper, as a backdrop to identifying research questions, I
briefly highlight a vision for a smart world (Section II). I then
discuss open research questions categorized into 8 topics
(Section III). The research discussed is representative rather
than complete. Two goals of the paper are: (i) to highlight a
number of significant research needs for future IoT systems,
and (ii) to raise awareness of work being performed across
various research communities.
II. VISION AND IOT SCOPE
Many people [8], including myself [28][29], hold the view
that cities and the world itself will be overlaid with sensing
and actuation, many embedded in “things” creating what is
referred to as a smart world. But it is important to note that
one key issue is the degree of the density of sensing and
actuation coverage. I believe that there will be a transition
point when the degree of coverage triples or quadruples from
what we have today. At that time there will be a qualitative
change. For example, today many buildings already have
sensors for attempting to save energy [7][38]; home
automation is occurring [3]; cars, taxis, and traffic lights have
devices to try and improve safety and transportation [9];
people have smartphones with sensors for running many
useful apps [2]; industrial plants are connecting to the Internet
[1]; and healthcare services are relying on increased home
sensing to support remote medicine and wellness [11].
However, all of these are just the tip of the iceberg. They are
all still at early stages of development. The steady increasing
density of sensing and the sophistication of the associated
processing will make for a significant qualitative change in
how we work and live. We will truly have systems-of-systems
that synergistically interact to form totally new and
unpredictable services.
What will be the platform or platforms that support such a
vision? One possibility is a global sensing and actuation utility
connected to the Internet. Electricity and water are two
utilities that can be used for a myriad of purposes. Sensing and
actuation in the form of an IoT platform will become a utility.
IoT will not be seen as individual systems, but as a critical,
integrated infrastructure upon which many applications and
services can run. Some applications will be personalized such
as digitizing daily life activities, others will be city-wide such
as efficient, delay-free transportation, and others will be
worldwide such as global delivery systems. In cities perhaps
there will be no traffic lights and even 3D transportation
vehicles. Smart buildings will not only control energy or
security, but integrate personal comfort, energy savings,
security and health and wellness aspects into convenient and
effective spaces. Individuals may have patches of bionic skin
with sensing of physiological parameters being transmitted to
the cloud which houses his digital health, and to the surrounding smart spaces for improved comfort, health,
efficiency, and safety. In fact, smart watches, phones, body
nodes, and clothes will act as personalized input to optimize
city-wide services benefiting both the individual and society.
Consequently, we will often (perhaps 24/7) be implicitly
linked into the new utility. Some examples of new services
include immediate and continuous access to the right
information for the task at hand, be it, traveling to work or a
meeting, exercising, shopping, socializing, or visiting a doctor.
Sometimes these activities will be virtual activities, or even
include the use of avatars or robots. Many outputs and
displays for users may be holographic. Credit cards should
disappear and biometrics like voice or retinas will provide safe
access to buildings, ATMs, and transportation systems.
A sensing and actuation utility will not only exist in public
spaces, but also extend into the home, apartments, and
condominiums. Here people will be able to run health,
energy, security, and entertainment apps on the infrastructure.
Installing and running new apps will be as easy as plugging in
a new toaster into the electric utility. One app may help
monitor and control heart rate, another perform financial and
investments services, another automatically ordering food and
wine, or even predicting a impending medical problem that
should be addressed early to mitigate or even avoid the
problem. Humans will often be integral parts of the IoT
system. The Industrial Internet is also a form of IoT where the
devices (things) are objects in manufacturing plants, dispatch
centers, process control industries, etc. Consequently, in the
future the scope of IoT is enormous and will affect every
aspect of all our lives.
III. RESEARCH
The spectrum of research required to achieve IoT at the
scale envisioned above requires significant research along
many directions. In this section problems and required
research are highlighted in 8 topic areas: massive scaling,
architecture and dependencies, creating knowledge and big
data, robustness, openness, security, privacy, and human-inthe-loop.
Each of the topic discussions primarily focuses on
new problems that arise for future IoT systems of the type
described in Section II. The research topics presented in each
case are representative and not complete.
Many important topics such as the development of
standards, the impact of privacy laws, and the cultural impact
on use of these technologies are outside the scope of the paper.
A. Massive Scaling
The current trajectory of the numbers of smart devices being
deployed implies that eventually trillions of things will be on
the Internet. How to name, authenticate access, maintain,
protect, use, and support such a large scale of things are major
problems. Will IPv6 suffice? Will protocols such a 6LowPAN
play a role? Will entirely new standards and protocols
emerge? Since many of the things on the Internet will require
their own energy source, will energy scavenging and
enormously low power circuits eliminate the need for
batteries? How will the massive amounts of data be collected, used, and stored? What longitudinal studies will be
performed? How will the real-time and reliability aspects be
supported [5][13]? How will devices including mobile devices
be discovered? Will the emergence of a utility model, if it
occurs, mean entirely new standards? How will such a utility
be achieved? It is unlikely that any solution immediately
becomes the norm. Many protocols and variations will coexist.
What will be the architectural model that can support the
expected heterogeneity of devices and applications?
B. Architecture and Dependencies
As trillions of things (objects) are connected to the Internet it
is necessary to have an adequate architecture that permits easy
connectivity, control, communications, and useful
applications. How will these objects interact in and across
applications [37]? Many times, things or sets of things must be
disjoint and protected from other devices. At other times it
makes sense to share devices and information. One possible
architectural approach for IoT is to borrow from the
smartphone world [2][4]. Smartphones employ an approach
where applications are implemented and made available from
an app store. This has many advantages including an
unbounded development of novel applications that can execute
on the smartphones. Various standards and automatic checks
are made to ensure that an app can execute on a given
platform. For example, the correct version of the underlying
OS and the required sensors and actuators can be checked
when the app is installed [12]. A similar architectural
approach for IoT would also have similar advantages.
However, the underlying platform for IoT is much more
complicated than for smartphones. Nevertheless, if IoT is
based on an underlying sensor and actuator network that acts
as a utility similar to electricity and water, then, different IoT
applications can be installed on this utility. While each
application must solve its own problems, the sharing of a
sensing and actuation utility across multiple simultaneously
running applications can result in many systems-of-systems
interference problems, especially with the actuators.
Interferences arise from many issues, but primarily when the
cyber depends on assumptions about the environment, the
hardware platform, requirements, naming, control and various
device semantics. Previous work, in general, has considered
relatively simple dependencies related to numbers and types of
parameters, versions of underlying operating systems, and
availability of correct underlying hardware. Research is
needed to develop a comprehensive approach to specifying,
detecting, and resolving dependencies across applications.
This is especially important for safety critical applications or
when actuators can cause harm.
Let’s consider a few examples of dependencies [21][31][32].
Assume that we integrate several systems responsible for
energy management (controlling thermostats [17], windows,
doors, and shades) and home health care (controlling lights,
TVs, body nodes measuring heart rate and temperature, and
sleep apnea machines [33]). If information can be shared, this
would allow the energy management system to adjust room
temperature depending on the physiological status of the residents as detected by the home health care system. Also,
integration will allow avoiding negative consequences. For
example, the integrated system will not turn off medical
appliances to save energy while they are being used as
suggested by the home health care system. In addition to these
advantages, all the systems can share sensors and actuators,
which will reduce cost of deployment, improve aesthetics of
the rooms, and reduce channel contention. However,
integrating multiple systems is very challenging as each
individual system has its own assumptions and strategy to
control the physical world variables without much knowledge
of the other systems, which leads to conflicts when these
systems are integrated without careful consideration. For
example, a home health care application may detect
depression and decide to turn on all the lights. On the other
hand, the energy management application may decide to turn
off lights when no motion is detected. Detecting and resolving
such dependency problems is important for correctness of
operation of interacting IoT systems.
Abstract—Many technical communities are vigorously
pursuing research topics that contribute to the Internet of Things
(IoT). Today, as sensing, actuation, communication, and control
become ever more sophisticated and ubiquitous, there is
significant overlap in these communities, sometimes from slightly
different perspectives. More cooperation between communities is
encouraged. To provide a basis for discussing open research
problems in IoT, a vision for how IoT could change the world in
the distant future is first presented. Then, eight key research
topics are enumerated and research problems within those topics
are discussed.
INTRODUCTION
mart devices. Smartphones. Smart cars. Smart homes.
Smart cities. A smart world. These notions have been
espoused for many years. Achieving these goals has been
investigated, to date, by many diverse and often disjoint
research communities. Five such prominent research
communities are: Internet of Things (IoT), Mobile Computing
(MC), Pervasive Computing (PC), Wireless Sensor Networks
(WSN), and most recently, Cyber Physical Systems (CPS).
However, as technology and solutions progress in each of
these fields there is an increasing overlap and merger of
principles and research questions. Narrow definitions of each
of these fields are no longer appropriate. Further, research in
IoT, PC, MC, WSN and CPS often relies on underlying
technologies such as real-time computing, machine learning,
security, privacy, signal processing, big data, and others.
Consequently, the smart vision of the world involves much of
computer science, computer engineering, and electrical
engineering. Greater interactions among these communities
will speed progress.
In this paper, as a backdrop to identifying research questions, I
briefly highlight a vision for a smart world (Section II). I then
discuss open research questions categorized into 8 topics
(Section III). The research discussed is representative rather
than complete. Two goals of the paper are: (i) to highlight a
number of significant research needs for future IoT systems,
and (ii) to raise awareness of work being performed across
various research communities.
II. VISION AND IOT SCOPE
Many people [8], including myself [28][29], hold the view
that cities and the world itself will be overlaid with sensing
and actuation, many embedded in “things” creating what is
referred to as a smart world. But it is important to note that
one key issue is the degree of the density of sensing and
actuation coverage. I believe that there will be a transition
point when the degree of coverage triples or quadruples from
what we have today. At that time there will be a qualitative
change. For example, today many buildings already have
sensors for attempting to save energy [7][38]; home
automation is occurring [3]; cars, taxis, and traffic lights have
devices to try and improve safety and transportation [9];
people have smartphones with sensors for running many
useful apps [2]; industrial plants are connecting to the Internet
[1]; and healthcare services are relying on increased home
sensing to support remote medicine and wellness [11].
However, all of these are just the tip of the iceberg. They are
all still at early stages of development. The steady increasing
density of sensing and the sophistication of the associated
processing will make for a significant qualitative change in
how we work and live. We will truly have systems-of-systems
that synergistically interact to form totally new and
unpredictable services.
What will be the platform or platforms that support such a
vision? One possibility is a global sensing and actuation utility
connected to the Internet. Electricity and water are two
utilities that can be used for a myriad of purposes. Sensing and
actuation in the form of an IoT platform will become a utility.
IoT will not be seen as individual systems, but as a critical,
integrated infrastructure upon which many applications and
services can run. Some applications will be personalized such
as digitizing daily life activities, others will be city-wide such
as efficient, delay-free transportation, and others will be
worldwide such as global delivery systems. In cities perhaps
there will be no traffic lights and even 3D transportation
vehicles. Smart buildings will not only control energy or
security, but integrate personal comfort, energy savings,
security and health and wellness aspects into convenient and
effective spaces. Individuals may have patches of bionic skin
with sensing of physiological parameters being transmitted to
the cloud which houses his digital health, and to the surrounding smart spaces for improved comfort, health,
efficiency, and safety. In fact, smart watches, phones, body
nodes, and clothes will act as personalized input to optimize
city-wide services benefiting both the individual and society.
Consequently, we will often (perhaps 24/7) be implicitly
linked into the new utility. Some examples of new services
include immediate and continuous access to the right
information for the task at hand, be it, traveling to work or a
meeting, exercising, shopping, socializing, or visiting a doctor.
Sometimes these activities will be virtual activities, or even
include the use of avatars or robots. Many outputs and
displays for users may be holographic. Credit cards should
disappear and biometrics like voice or retinas will provide safe
access to buildings, ATMs, and transportation systems.
A sensing and actuation utility will not only exist in public
spaces, but also extend into the home, apartments, and
condominiums. Here people will be able to run health,
energy, security, and entertainment apps on the infrastructure.
Installing and running new apps will be as easy as plugging in
a new toaster into the electric utility. One app may help
monitor and control heart rate, another perform financial and
investments services, another automatically ordering food and
wine, or even predicting a impending medical problem that
should be addressed early to mitigate or even avoid the
problem. Humans will often be integral parts of the IoT
system. The Industrial Internet is also a form of IoT where the
devices (things) are objects in manufacturing plants, dispatch
centers, process control industries, etc. Consequently, in the
future the scope of IoT is enormous and will affect every
aspect of all our lives.
III. RESEARCH
The spectrum of research required to achieve IoT at the
scale envisioned above requires significant research along
many directions. In this section problems and required
research are highlighted in 8 topic areas: massive scaling,
architecture and dependencies, creating knowledge and big
data, robustness, openness, security, privacy, and human-inthe-loop.
Each of the topic discussions primarily focuses on
new problems that arise for future IoT systems of the type
described in Section II. The research topics presented in each
case are representative and not complete.
Many important topics such as the development of
standards, the impact of privacy laws, and the cultural impact
on use of these technologies are outside the scope of the paper.
A. Massive Scaling
The current trajectory of the numbers of smart devices being
deployed implies that eventually trillions of things will be on
the Internet. How to name, authenticate access, maintain,
protect, use, and support such a large scale of things are major
problems. Will IPv6 suffice? Will protocols such a 6LowPAN
play a role? Will entirely new standards and protocols
emerge? Since many of the things on the Internet will require
their own energy source, will energy scavenging and
enormously low power circuits eliminate the need for
batteries? How will the massive amounts of data be collected, used, and stored? What longitudinal studies will be
performed? How will the real-time and reliability aspects be
supported [5][13]? How will devices including mobile devices
be discovered? Will the emergence of a utility model, if it
occurs, mean entirely new standards? How will such a utility
be achieved? It is unlikely that any solution immediately
becomes the norm. Many protocols and variations will coexist.
What will be the architectural model that can support the
expected heterogeneity of devices and applications?
B. Architecture and Dependencies
As trillions of things (objects) are connected to the Internet it
is necessary to have an adequate architecture that permits easy
connectivity, control, communications, and useful
applications. How will these objects interact in and across
applications [37]? Many times, things or sets of things must be
disjoint and protected from other devices. At other times it
makes sense to share devices and information. One possible
architectural approach for IoT is to borrow from the
smartphone world [2][4]. Smartphones employ an approach
where applications are implemented and made available from
an app store. This has many advantages including an
unbounded development of novel applications that can execute
on the smartphones. Various standards and automatic checks
are made to ensure that an app can execute on a given
platform. For example, the correct version of the underlying
OS and the required sensors and actuators can be checked
when the app is installed [12]. A similar architectural
approach for IoT would also have similar advantages.
However, the underlying platform for IoT is much more
complicated than for smartphones. Nevertheless, if IoT is
based on an underlying sensor and actuator network that acts
as a utility similar to electricity and water, then, different IoT
applications can be installed on this utility. While each
application must solve its own problems, the sharing of a
sensing and actuation utility across multiple simultaneously
running applications can result in many systems-of-systems
interference problems, especially with the actuators.
Interferences arise from many issues, but primarily when the
cyber depends on assumptions about the environment, the
hardware platform, requirements, naming, control and various
device semantics. Previous work, in general, has considered
relatively simple dependencies related to numbers and types of
parameters, versions of underlying operating systems, and
availability of correct underlying hardware. Research is
needed to develop a comprehensive approach to specifying,
detecting, and resolving dependencies across applications.
This is especially important for safety critical applications or
when actuators can cause harm.
Let’s consider a few examples of dependencies [21][31][32].
Assume that we integrate several systems responsible for
energy management (controlling thermostats [17], windows,
doors, and shades) and home health care (controlling lights,
TVs, body nodes measuring heart rate and temperature, and
sleep apnea machines [33]). If information can be shared, this
would allow the energy management system to adjust room
temperature depending on the physiological status of the residents as detected by the home health care system. Also,
integration will allow avoiding negative consequences. For
example, the integrated system will not turn off medical
appliances to save energy while they are being used as
suggested by the home health care system. In addition to these
advantages, all the systems can share sensors and actuators,
which will reduce cost of deployment, improve aesthetics of
the rooms, and reduce channel contention. However,
integrating multiple systems is very challenging as each
individual system has its own assumptions and strategy to
control the physical world variables without much knowledge
of the other systems, which leads to conflicts when these
systems are integrated without careful consideration. For
example, a home health care application may detect
depression and decide to turn on all the lights. On the other
hand, the energy management application may decide to turn
off lights when no motion is detected. Detecting and resolving
such dependency problems is important for correctness of
operation of interacting IoT systems.