Implementation of IoT in Healthcare System

This paper discusses the implementation of IoT in healthcare system and the need for security measures to protect sensitive data. It covers different authentication algorithms like ECC and CoAP and their effectiveness in ensuring data security. The paper also talks about different proposals for group authentication and smart health gateways.

Implementation Of IoT In Health Care
System
61234Beulah Moses- 11
Masters in IT – Networking
[e-mail]
ABSTRACT – Internet of things refers to the computing system where each entity is equipped with sensor
and microcontroller. The microcontroller along with the sensor is used for communicating with the real
world. In the IOT system, the devices are connected with each other through various sensors and the
communication between the devices takes place over the internet. The data, which is generated by the devices,
is stored in the cloud to work with them whenever necessary. Authentication is one of the primary and
important means to ensure that data is secure and protected. The architecture required to implement the
authentication algorithm has been discussed as well. The ECC algorithm over the CoAP protocol has been
used. The authentication procedure that has been discussed in this paper provides an efficient mechanism,
capable of ensuring strong security of the system.
Keywords— CoAP, ECC, authentication, security
1. INTRODUCTION
Internet of things has evolved over the years,
thanks to the advancement of various interconnected
technologies like IPv6, wireless network and
microcontroller and sensor electronics. The evolution
of the IoT has heavily influenced various sectors like
business, sports, health and many more. IoT in
healthcare is an important research topic as the
technology has lot of potentials for the sector in terms
of bringing more automation and transparency in
healthcare administrations (Gope & Hwang, 2016 ).
However the threats that the technology poses along
with the benefits needs careful attentions. The task to
control the systems and integrate it with the IoT
technology is indeed challenging. Researchers are
particularly concern about this, even more than the
benefits that the system will provide following the
implementation . Different methods have been
provided by different researchers to control IoT
devices and the topic has managed to get widespread
attentions and provides an excellent opportunity to
conduct further research in the field to come up with
even better solutions (Wu et al., 2017).
Data protection is one of the critical issues that
need to be considered when dealing with the network
devices. Security plays a vital role in the context of
IoT technology (Tyagi , Agarwal & Maheswari ,
2016). In case there is a malicious attack or
interference takes place and the attacker becomes
successful in hacking the network of the system then
they will be able to steal important data that is
intended to be kept safe and private for the data is
highly sensitive in nature. In order to protect the
devices from outside access that is intended for
illegal purpose, it is important to have the correct
security measure in practise. Authentication has an
important role to play to ensure security of the IoT
devices. Different researchers have provided different
mechanism for authentication for the IoT devices and
network (Bhatt, Dey & Ashour, 2017). However the
mechanisms have certain drawbacks. The
mechanisms have not considered the limitations of
IoT devices which have often very limited resources
in terms of memory and processing power. In order to
design effective authentication techniques it is
important to combine the characteristics of the end
devices and a proper balance should be maintained
between the available resources so that efficient,
secure and suitable authentication mechanism can be
designed that suits the need of the IoT environment
(Laplante & Laplante , 2016).
Here the overall introduction of the topic is given.
Factors like importance of the topic, justification for
the topic selections and the need for the research on
the topic have been discussed. The process to ensure
the data security in IoT is challenging task. The
report will discuss the methods to ensure the data
security and how it can be implemented using the
ECC authentication algorithm.
2. BACKGROUND/LITERATURE REVIEW
Li et al.,( 2018) have talked about the importance
of RFID technology for the device authentication in
the IOT environment. RFID or the radio frequency
identification technology helps to identify a device
remotely with the RFID tag. The authors points out
that RFID technology is highly efficient I recognizing
devices. The authors further add that in the IOT

environment, millions of devices are connected to the
internet and with each other as well. Hence it is
important to implement techniques that can help to
identify the devices amongst the polls of connected
devices. RFID technology has lot of potential in this
context. RFID tags has the ability to store
information and send this information remotely, thus
enabling the wireless communication between the
devices and the database that store information about
this devices. This information can be then used for
the identification of the devices. However the authors
suggest that there should be proper data monitoring
technology in order to derive useful information from
the data sent by the devices connected over IP
network. Once the data is sent by the smart and RFID
enabled devices over the IP network, the data is then
processed in the central data base and converted into
human readable format. One of the most important
features that make RFID tags more efficient than the
standard barcode technology is the ability of the
RFID tag to support more advanced communication
style. In order to read information from the RFID tag
it is not mandatory for the device to be in the line of
sight which means that the device can be tracked
from anywhere. In the IOT environment, wireless
communication plays an important role and
technology like this, according to the authors, only
increase the efficiency of the communication with
ease in device identification.
Lopes & Hilgert (2017) have proposed for two
phase algorithm for group authentication: pre
authentication phase and group authentication phase
In the pre authentication phase the GA of the group
who is responsible for creating the group generates a
public key and associated private keys. This keys are
then used for authenticate the devices in the group.
The keys are generated using the threshold
cryptosystem. In the group authentication phase the
authenticity of every devices in the group is checked
using the private and public keys that were generated
in the pre authentication phase. The GA in this phase
creates another random secret key that is shared
among all the devices in the group and the devices
need to address the random key to complete the
authentication process in the group authentication
phase.
Jan et al., (2016) have provided a mutual
authentication schema for the IoT implementation in
health care. This schema helps to validate the
identities of the IoT devices. The schema first
identifies the devices in the IoT environment before
the devices are actually integrated in the real
network. In order to perform the authentication in the
IoT environment before integrating with the network
the authors have proposed for “decreased
communication overhead”. The schema is based on
the. Constrained Application Protocol or CoAP. The
authentication is performed using the 128-bit
“Advanced Encryption Standard” or AES. The
authors suggest claims that due to such high level of
encryption value the devices are highly secured in the
IoT environment where the security playsa major role
for successful implementation of the technology. In
the CoAP technique, the identity of the server and the
client is first is verified. Based on the identity the
system then allows the client to access the server
based on the conditions that was determined by the
protocol in the request made by the client. Thus it is
not easy for the user to access the server without
performing proper authentication and the verification
of the request is also necessary to get access to the
server.
Hofheinz & Jager (2016) have proposed for
public key algorithm for the authentication purpose.
Data that is collected by the IoT devices is stored in
the cloud servers and secured database. However it is
important to note that in order to protect the data it is
very much important to protect the authenticity and
the integrity of the data. The integrity of the data can
be maintained by the mechanism called “message
digest” which is a secured hash algorithm. The
algorithm produces predefined hash value to secure
the digital content. It is not easy to access a digital
content and modify it without the proper
authentication if the content is secured with a
predefined hash value. The authenticity of the data
can be maintained by the public key based key based
digital signature technique. In the public key based
cryptography algorithm two keys are generated
known as public and private key. The private key
belongs to the owner of the data which needs to be
used to prove the claim of the user that the user really
owns the data. The public key is for the use of other
users who wants to access the content. The public
key is accessible to anyone who wants to verify the
signature of a digital content or data.
Stallings (2016) has proposed for hashing
algorithm for digital content cryptography. The
signature for the data is produced by hashing the
digital content and a hash value is produced in this
process. The value is attached to the content as the
form of digital signature. In order to the read the
content the digital content needs to be hashed again
and in the second step the hashed value which is
reconstructed in the hashing of the content has to
matched with the public key along with the signature
that is attached with the content.
Su, Wong, & Chen (2016, May) have proposed for
a group authentication technique. The technique is
based on the Threshold Cryptography. The scheme is
used for the authenticate devices in a group. The

authors describe that in the IoT environment lot of
devices are connected together. Hence the task of
securing those devices is a challenging option.
However with the use of the group authentication
technique it is possible to authenticate devices in a
group. The authors have used the method of releasing
the token to perform the authentication. The method
is based on the “Shamir’s secret sharing scheme”.
The algorithm is implemented in the Wi-Fi
environment. Each group in the network constitutes a
set of devices and the devices communicate with each
other by sharing secret key. There may be any
number of groups and the range of the connectivity is
decided based on the Wi-Fi standard. The groups can
even overlap with each other and one device may
belong to more than one group. However there is a
primary device in every group which is responsible
for monitoring the communication in the group. Each
time a new device is added to the group, a new key
pairs is generated which is distributed by the primary
device within the group to keep the existing devices
in the group updated about the inclusion of the new
devices in the group. The TCGA algorithm
constitutes of five key modules 1. Distribution of
key. 2. Updating of key. 3. Generation Group Credits.
4. Authentication of Listener. 5. Message Decryption
Moosavi et al., (2015) have proposed for SEA
architecture for IoT based healthcare system. The
architecture consist of smart health gate-ways. The
health related information is captured from the
sensors that are either body-worn or implanted. The
sensors collect data of the patient and send it to the
database for monitoring purpose. The architecture
consists of medical sensor network, smart heath
gateway and back end system. The medical sensor
networks helps in sensing, identifying and
communicating the medical related data. Sensors are
attached with the patient. The sensors are highly
advanced and help to collect necessary information
about the patient condition. The sensors measure
body temperature and collect data about the bio-
medical and context signal. This data are useful to
monitor the condition of the patient. The sensors can
also supplement the data with the context information
like date, time and location which helps toget precise
information about the medical condition of the
patient. The bio medical and the context signal that is
captured by the sensors are transmitted to the
gateway. The data is sent to the gateway with the
help of wired and wireless communication protocol.
the communication protocols include standard
communication standards like serial , SPI , Bluetooth
technology. Signal can also be sent using the Wi-Fi
or IEEE 802.15.4 wireless communication standard.
Rahman et al., (2015, January) have proposed for
smart health gateway. Smart health gateway which
supports the communication protocol serves as a
connecting point between the MSN and the local
switch or network. Data generated from different sub
-networks are received by this gateway. The protocol
conversion is also performed by the gateway. The
gateway also aggregates the collected data and is also
capable in data filtering. The gate way even provides
some higher level service like dimensionality
reduction of the collected data. The back end system
constitutes the remaining part of the architecture. It
includes a cloud platform where the data is stored for
processing. The system also includes data warehouse
and big data analytic servers where data are analyzed
to extract the meaningful information from the
collected data that helps to find the relevant
information about the patient. The back end system
also consists of local data base of the hospital where
the data is stored temporarily before it is sent to the
cloud server and big data analytics server. The
system also consists of web clients which provides
the interface for the data visualization and data
apprehensions.
Porambage et al., (2014) have proposed for two
phase authentication protocol to authenticate and
secure the IoT devices. According to the authors the
protocol is highly efficient for authentication
purpose. In the wireless sensors networks that
follows centralised architecture consists of a central
entity. the sensor nodes in the network collects
information from the sensors and send it to the
central entity that is responsible tom maintain the
centralised network, the fadta is themn proceesed by
the central entity and the information is provided over
the network. However IOT follows distributed
network architecture. There is no central unit that
collects and process the information. The mechanism
is completely different from the centralised network.
Here the sensor nodes are responsible for sensing the
data. The data is then processed by the sensor nodes
itself and then the information is exchanged with
other nodes in the network. However there are certain
security concern that needs to be addressed while
following such distributive network architecture.
There are serious threats of the devices to be hacked
and once a node is hacked it is possible to exploit
other nodes in the network as well. once the nodes
are hacked it is possible to obtain sensitive
information from the nodes and based on the field of
application the sensitivity of the data varies. When
implementing IoT in the context of healthcare it is
much more important to secure the information with
proper authentication technique. The authors have
proposed two phase authentication technique. In this
proposed technique the authors describes the
mechanism to authenticate the sensor nodes and the
devices that are used for end to end communication.

In the first phase the nodes generates a authentication
key to be used by the communicating devices. In the
next phase the communicating devices will generate
another key. The key will then be verified by the
communicating node and if matches only then the
communication will takes place. The mechanism, as
per the authors will enhance the security of the
devices and also help to authenticate the devices
more securely.
Lee, Alasaarela & Lee (2014, February) have
suggested for a authentication scheme for securing
the IoT servers. The scheme is based on Elliptic
Curve Cryptography (ECC) based algorithms. The
authentication protocol proposed by the authors is
applicable for the embedded devices that follow the
HTTP protocol. The protocol makes use of the
cookies generated by the HTTP protocol for
authenticate the devices. The devices need the
TCP/IP configuration to be connected with the
protocol. The embedded devices are often limited in
size and processing power. That is why the algorithm
designed for the embedded system has to be efficient
and it has to address the constraint that the embedded
devices bring in the IoT environment. The
architecture that has been proposed by the authors
uses HTTP cookies which, according to the author
have been optimized so that it fit in the constrained
environment of embedded devices. The protocol
consists of three phases namely Registration phase,
Pre-computed and login phase and authentication
phase. In the registration phase the devices register
with the cloud servers and upon successful
registration the server send back a cookie which is
stored by the device. In the next phase or the Pre-
computed and login phase, the device has to send a
login request to login. Once the login request is
accepted the device enters into authentication phase.
In the authentication phase the device needs to send
the cookie provided by the server during the
registration phase. The server then checks if the
cookie matches with the cookie provided by the
server during the registration phase. The device is
authenticated only if the cookies matches, otherwise
error message are generated by the server. The
authors claim that the mechanism is quite useful and
advanced in managing authentication related issues.
3. SOLUTIONS
Based on the literature review the project finds out
the following requirements:
 Review of the authentication issues in the
IoT enabled healthcare system
 Design of proper authentication algorithm
 Review of the algorithm
 Comparison of the algorithms proposed
by previous works
 Suggest the most appropriate algorithm
based on the assessment of the strength
and weakness of other proposed
techniques by previous researchers.
4. Future Research
One of the major challenges that make the IOT
environment venerable to security threats is the lack
of proper security measure for the device
authentication. There are lot of security issues in the
IOT environment. However the prevent resource
exhausting is the most concerning fact that the
developers must address in order to maintain the
device security intact in the IOT environment. In
order to propose the effective security algorithm for
the IOT devices the resource constrains must be taken
care of. IOT devices are often resources limited. The
devices have very limited resources in terms of
processing power and storage memory. Hence the
algorithm must be optimized in such a way it
supports the limited processing power and storage of
the IOT devices. The mechanism that has been
proposed in the report has been optimized according
to the resources available. The mechanism is based
on the Constrained Application Protocol (CoAP) [31]
and Elliptic Curve Cryptography [32].
The application protocol or is designed in
accordance with the IETF working group. It provides
overview about the Constrained Restful Environment
(CoRE). The knowledge about the CoRE helps to
define the implementation architecture that is suitable
for the the sensor nodes implemented in the highly
constrained environment like IOT. The CoAP
protocol is highly efficient to create communication
between these constrained nodes. The protocol
defines the web interfaces that help to make
communication between the nodes to make device
communication over the connected network. In the
figure 1, different protocol stack has been shown.
These protocols are commonly used in the IOT
environment.
In order to understand the effectiveness of the
CoAP protocol for the IOT environment, it is
important to have in-depth knowledge about the most
widely used protocol that has almost made
dominance on the internet communication
technology. It is known as The Hypertext Transfer
Protocol or HTTP. In order to understand the reason
why the HTTP protocol is not chosen for the IOT
implementation, despite it being so popular and
widely used for the internet communication, the
drawbacks of the protocol must be clearly defined
and also needs to be carefully analyzed. HTTP is
basically a structured text that finds the logical link or
the hyper link between the nodes that contains the
text. This links are used by the protocol to facilitate
communication between the nodes. With the

introduction of the Internet of the things or IOT, the
definition of the internet has been completely
redefined. The internet is not all about the human
interaction anymore. With the IOT, machines and the
devices are getting connected to the internet in a
rapid rate. With the context of the internet getting
redefined, the requirements for the communication
are also changing. The IOT communication has some
special needs which the HTTP protocol is not
efficient to address. In IOT communication, the
information generated by one node needs to mapped
to all the nodes that participates in the
communication. small packets of information must be
shared in high volume due to vast amount of data
generated by the devices or the communication
nodes. HTTP protocol is not efficient in addressing
these requirements of IOT communication. the
important feature that makes the CoAP appropriate
for the IOT communication is that it allow machine
to take the roles of both client and server and also
allows to switch between these roles whenever it is
necessary. It also supports asynchronous message
transfer over the protocol which follows datagram
orientation. One popular example of such protocol is
the UDP protocol. An optional request or response
layer is also included with the CoAP messaging for
providing connection that is reliable like the
Transmission control protocol or TCP. The CoAp
layer has been shown in the figure 2.The operational
layer is useful for the dealing with the UDP protocol
as well as dealing with the asynchronous interactions
between the communicating needs. A 4 byte header
file is generated for minimizing the traffic due to
traffic overhead. CoAP includes methods like GET,
POST, PUT and DELETE which provides codes for
the device to response to the communication request.
The code is also necessary for reflecting the
execution status for the client request.
CoAP provides four different types of messages:
CON Message:
It means “Confirmable” request. When a CON
message is sent by a source node, then it is the
responsibility of the recipient to send the response
message using the ACK or the Acknowledge
message. The message is of high importance and
must be treated with importance .
NON Message:
It refers to the message that is “Non-
Confirmable”. Whenever a NON request is sent by
the sending node, the is no need for the recipient to
respond to the message. The message is not of much
importance.
ACK Message:
It refers to “Acknowledgement” messages.
Once the sending node sends the CON message, it
should be acknowledged by the recipient. However it
is not sufficient to acknowledge the message by the
recipient the sending node must be made aware of the
fact that the recipient has received the message and it
should be forwarded to the sending node. The
recipient must sent the ACK message to the response
of the CON message. The ACK message may also
contain information about the details about the
message processing.
RST Message:
It refers to the “RESET “message. Now it might be
possible that during the communication there occur
errors due to reason like network traffic, internet
speed. Now in order to make the communicating
node aware of this, the recipient of the message must
send RST message. It will help the sending node to
understand that error has been occurred in the
communication process. in case the recipient does not
make the sending node of this communication error,
it will continuously send message to the recipient, it
will not only increase traffic over the network, a lot
of data packet will remain on the network without
processing which will affect the communication
between other communicating nodes connected to the
same network. The RST message will help the
sending node to understand that the recipient is not
able to understand the message or the recipient is no
longer interested in receiving the message which will
help to avoid network traffic due to sharing of
message without any particular purpose.
In order to achieve security restrictions of similar
level, ECC considers key of smaller sizes. Although
there are several other asymmetric cryptographic
keys, but the security level provided by the ECC
algorithm is much better and improved. Those
features provided by the other algorithms considers
larger key sizes, for instance a 256-bit symmetric key
must be secluded by at least 15,000-bit RSA, on the
other hand, ECC uses an asymmetric key size of only
512 bits to ensure equivalent security level. This
decrease in the key size makes it possible for
significant cost saving and more compacted design
execution. Chips that are smaller are able to run
cryptographic process in a much faster rate. It also
minimizes the power consumption thus increase the
efficiency .these features are especially appropriate
for environments where there are resource constrain
issues. A comparison of key size with equivalent
security levels between ECC and RSA has been
provided in the subsequent section.
Key size
( ECC)
Key size
( RSA)
Reduction ratio
(approximate)
162 1024 1:16
256 3074 1:12

383 7684 1:20
512 15365 1:30
The authentication mechanism proposed here will
help to implement ECC authentication mechanism
over CoAP connection. These two approaches when
combined will help to optimize overhead to the IOT
network. It will further help in minimizing the
communication as well as the pocessing power that is
required to make authentication of the IoT devices. It
is also effective in achieving powerful and efficient
security for the IoT devices.
Authentication mechanism can be passing through
multiple stages.
Stage1:
It is the initialization phase. Here the Control
system generates a private key that is used for
communication with the ECC.
Stage2:
It is the device registration phase. It includes the
pre authentication process over CoAP where IoT
devices are checked if it is already authenticated or
not. Control station will then checks the device ID
that will help to find out whether there is a
corresponding entry for it. If there is no entry of
device then an ID will be generated with the help of
control private key. Along with it an encrypted
password will be generated which will be stored back
in the IoT device.
Stage3:
Mutual authentication stage, IoT device use this
password to generate authentication key and send it
back to the control system when it is try to connect it.
Control system check these key using corresponding
IoT entries stored at the control system.
Stage4:
All traffic pass between IoT devices and control
station then will be encrypted and secured against
different types of attack. Figure 5 proposed
authentication mechanism shows the detailed steps of
proposed authentication method between IoT device
and control station.
5. Advantages/ Disadvantages (5 marks)
Constrained Application Protocol can be referred
to as the web transfer protocol that is specially
designed in order to make it compatible with
constrained devices as well as constrained networks
CoAP are specially appropriate for designing
protocol that implements a request/response based
interaction that is implemented for communication
between the endpoints of communicating nodes or
the networks
CoAP contains some key concepts of the Web
including URIs and Internet media types
CoAP happens to be very common and at the same
highly reliable. It is an effective choice for the
application of data transferring, especially for the
IoT environment.
Elliptic Curve Cryptography refers to asymmetric
cryptographic algorithm. It is applied for providing
security and that too with the same level as provided
by RSA. However the special feature of ECC is the
key size as it works with much smaller key sizes.
ECC works with much smaller key sizes while
providing security of higher level .
Due to smaller devices and lower processing
power the IOT environment is highly constrained.
However ECC works finely with the constraint
environment of IOT
ECC has the ability to provide encryption that is
highly reliable. It also helps to minimize the overhead
of the IOT network.
6. Conclusion
In this paper, a thorough review has been
conducted on the use of IoT in healthcare. Security
issues are highly critical when dealing with the
healthcare system. In order to overcome the issues
authentication mechanism has been proposed. The
mechanism is highly reliable. While proposing the
mechanism it had been made sure that the mechanism
is compatible with the IOT devices. The IOT devices
have limited memory and also have limitation in
terms of processing power. Hence it has been made
sure that the proposed mechanism address the
constrains of The proposed reliable authentication
mechanism mainly depends on CoAP with ECC
algorithms. Proposed method fit the requirements of
IoT constrained devices. Small ECC key has reduced
the calculation requirements while providing a
powerful encryption better than other types of
cryptography.
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