Wireless body area networks (WBANs), a relatively new technology that has emerged in response to the exponential growth in the demand for healthcare, have shown themselves to be promising and are already being utilized extensively in the field of human health monitoring. Within the scope of this paper, a conceptual framework of an optimal workload allocation algorithm for edge computing-based WBAN systems is presented. Users can enhance their WBAN system by optimizing the workload allocation algorithms, which will result in a reduction in latency, energy consumption, job failure, and communication load. A final evaluation of the effectiveness of the proposed strategy was carried out, and the results of the experiment demonstrate that the proposed approach was successful in improving the quality of the system by lowering the number of transmission failures and the amount of power that was consumed.
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979-8-3503-6491-0/24/$31.00 ©2024 IEEE
Conceptual Framework for the Optimization of
Edge Device Workload Allocation in Wireless
Body Area Networks
Sachinthani Alahakoon
Faculty of Information Technology,
City University Malaysia,
Petaling Jaya 46100,
Malaysia
sachi@gwu.ac.lk
Mustafa Muwafak Alobaedy
Faculty of Information Technology,
City University Malaysia,
Petaling Jaya 46100,
Malaysia
mustafa.theab@city.edu.my
Yousef Fazea
Department of Computer Sciences
and Electrical Engineering,
Marshall University, One John
Marshall Drive, Huntington, WV
25755, USA,
fazeaalnades@marshall.edu
Abstract— Wireless body area networks (WBANs), a
relatively new technology that has emerged in response to the
exponential growth in the demand for healthcare, have shown
themselves to be promising and are already being utilized
extensively in the field of human health monitoring. Within the
scope of this paper, a conceptual framework of an optimal
workload allocation algorithm for edge computing-based
WBAN systems is presented. Users can enhance their WBAN
system by optimizing the workload allocation algorithms, which
will result in a reduction in latency, energy consumption, job
failure, and communication load. A final evaluation of the
effectiveness of the proposed strategy was carried out, and the
results of the experiment demonstrate that the proposed
approach was successful in improving the quality of the system
by lowering the number of transmission failures and the amount
of power that was consumed.
Keywords— Workload allocation, wireless body area
networks, edge computing
I. INTRODUCTION
Through the enhancement of patient care, as well as the
optimization of clinic operations and financial measures, the
Internet of Medical Things (IoMT) contributes to the overall
betterment of the healthcare industry [1]. Some important
applications of IoMT include telemedicine services, with
secure and reliable connectivity, healthcare professionals can
remotely examine patients, provide consultations, and monitor
their progress. IoMT streamlines healthcare operations by
automating administrative tasks. This leads to cost savings,
increased productivity, and improved overall efficiency in
healthcare delivery. Furthermore, IoMT enables continuous
remote patient monitoring and transmitting patient data to
healthcare providers [1]. Patients' medical data collected via
wearable healthcare devices such as wearable sensors and
smart implants, enable continuous monitoring of chronic
conditions like diabetes, and cardiovascular diseases also
helps healthcare providers to identify trends, predict disease,
and provide personalized treatments.
This form of network is known as Wireless Body Area
Network (WBAN) and comprises gateway devices, sensors,
and additional devices located throughout the body [2]. Edge
computing is gaining popularity in WBAN because it enables
organizations to achieve near-real-time results by processing
data as close to the source as possible. Its applications go
beyond the medical field to include sports, entertainment,
aerospace, and the military, among others. As a result, it adds
greatly to both economic and social value [3].
A. WBAN for Health: Sensors and Computing
A WBAN is a network that interconnects sensor nodes,
enabling communication between individuals and objects.
The utilization of a singular WBAN enables the monitoring
variety of biomedical sensors that track a patient's vital signs.
Biomedical sensors can monitor several vital indicators such
as temperature, cardiac rate, breathing rate,
electroencephalogram, electrocardiogram, blood pressure,
and glucose level [4]. Every set of vital signs is represented by
a unique type of clinical data that is completely different in
format and content from the other data sets. As a result, the
data collected by biomedical sensors are heterogeneous
depending on the category of data, it requires different types
of processing by medical professionals [5],[6].
WBAN can be divided into three types depending on the
compute location. These are Cloud computing, fog
computing, and edge computing-based WBAN systems. Edge
computing is a computationally efficient, safe, private, and
cost-effective approach for leveraging the Internet of Things
(IoT) at scale. It eliminates the possibility of data breaches or
network overloads, making it a superior alternative to fog
computing and cloud computing. In addition, edge computing
provides resilience and redundancy for mission-critical tasks.
However, it does encounter challenges in the WBAN
application process. The WBAN method utilizes several inbody, on-body, and off-body biomedical sensors, requiring the
edge computing device to process large quantities of data
simultaneously [3]. Due to the time-sensitive nature of such
applications, it is necessary to identify the most desired
processing requirements and prioritize them. Following the
development of diverse WBAN models, researchers focus on
enhancing the quality of service by addressing and
overcoming technological challenges. With the help of rapid
growth in biomedical sensors, low-power Integrated Circuits
(ICs), and improvements in communication speed WBAN
technology has emerged as an innovative, cost-effective
solution for continuous health monitoring methods offering
real-time updates. Consequently, the field of WBAN has
attracted many researchers, particularly in optimizing
resource and workload allocation strategies. These efforts aim
not only to elevate service quality but also to bolster security
measures for protecting sensitive medical data and to drive
down the operational costs associated with health monitoring
systems [3].
B. Challenges in Workload Optimization
Prior to making critical medical decisions, collected raw
data should be processed and analyzed. Therefore, the
2024 International Symposium on Networks, Computers and Communications (ISNCC) | 979-8-3503-6491-0/24/$31.00 ©2024 IEEE | DOI: 10.1109/ISNCC62547.2024.10759005
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processing of data is the most important aspect of WBANs.
WBANs employ varied utilize different data processing
strategies. Particularly, data processing for edge-based
applications can be performed by edge processors themselves.
Due to the urgent nature of many medical applications of
WBANs, the most critical processing requirements must be
identified. Processing requirements and processing priorities
can be diverse significantly, reflecting the unique needs of
each user.
The WBAN system faces a significant challenge in finding
an optimal strategy to accomplish the user's goal by allocating
workload to edge nodes [1]. By using a suitable algorithm, it
can achieve the desired performance, reduce processing delay
or latency, lower power consumption, and enhance the
throughput and growth of real-time applications that require
local processing and storage capabilities [1]. The goal of this
research is to introduce a conceptual framework to reduce
processing delays and achieve the desired performance. Given
the nature of the application, the most critical factors are
speed, reliability, latency, and energy consumption. However,
current routing algorithms cannot fully address these issues
due to high propagation loss and challenging channel
conditions [7].
The objective of this study is to significantly enhance the
efficiency and speed of WBAN while reducing latency,
lowering energy consumption, and minimizing the occurrence
of task failures, by optimizing workload allocation algorithms
for different WBANs with various edge device processing
elements.
Remote patient monitoring has gained significant
popularity in recent years driven by population growth and the
impact of the pandemic. Many hospitals and doctors have
adopted the WBAN system for patient monitoring. Integrating
edge computing with WBAN enables the health sector to
extend its medical resources flexibly across locations while
reducing time and costs. Edge computing has the ability to
decrease latency, ultimately enhancing performance for the
client [8].
Medical professionals increasingly use biomedical sensors
to monitor various human body variations, aiming to
maximize the benefits of resources within the WBAN system
[9]. Considering the system integrates numerous sensors, the
edge processor faces a significant workload. The processor in
the edge device can discontinue or become overwhelmed,
leading to slowdown and reduced efficiency coupled with
high power consumption due to its heavy workload.
Therefore, there must be an optimal workload allocation
method for the WBAN system to achieve effective results.
While there are various workload allocation methods for
the edge device across multiple applications, these methods
often fall short for time-critical applications. Hence, there is a
pressing need to develop an optimal workload allocation
algorithm specifically designed for time-critical edge
computing applications such as WBAN. By employing
optimizing workload allocation algorithms for specific
applications with different edge processors, users can
experience a significantly improved and more responsive
WBAN system.
II. LITERATURE SEARCH AND REVIEW
Prior research has suggested multiple strategies for
distributing edge workloads among distinct applications. The
majority of research is centered around work offloading
methods and resource allocation algorithms in order to
optimize device time delay and energy usage in edge settings.
The years between 2015 and 2020 witnessed a substantial
surge in edge computing, which garnered considerable interest
from both industry and academia.
In [10], provides a comprehensive analysis of workload
and resource allocation in edge-based WBANs. The
assessment suggests that although there have been some
investigations on workload distribution for fog and cloud
computing, only the studies on task offloading and resource
allocation were directly relevant to edge computing. Here are
the pertinent studies that have been undertaken in recent years.
In their work, Yuan et al., [7] presented a Two-Stage
Potential Game-based Computation Offloading Strategy. This
strategy attempts to optimize resource consumption in
WBANs by taking into account task and user priorities.
They initiate the process by articulating the challenge of
maximizing system utility, specifically focusing on the quality
of service (QoS) of activities. Computation offloading was
modeled using reward, cost, and penalty functions. They
enhance the feasibility of the algorithm and decrease the
expense of computation by implementing a two-stage
optimization approach. This method effectively resolves the
problem of conflicting strategies in the strategy space of the
possible game model [7]. The control mechanism presented in
[11] utilizes bargaining game theory to facilitate resource
sharing across the multi-access edge computing-assisted
WBAN platform, which has limited computing and
communication resources. The proposed approach evaluated
the advantages of both intra- and inter-WBAN interactions.
In 2023, Li et al. [12] discussed resource allocation and
data offloading strategy for an edge-based telemedicine
system. Utilizing cooperative game-based development, they
allocated slots in WBAN to minimize system costs.
Additionally, they employed a bilateral matching game-based
system to optimize the data offloading problem in edge
computing networks.
Furthermore, researchers have recorded the practice of
delegating tasks as a means of distributing workload. Zhang
and Zhou introduced computational task offloading strategies
that leverage mobile cloud computing and mobile edge
computing for WBAN [13]. They devised a three-tier system
along with an optimization technique to decrease expenses
associated with energy usage and latency.
A study was conducted to examine the efficacy of
optimization methods for WBANs. Every optimization
approach possesses unique advantages and disadvantages,
simplifying the process of choosing the appropriate strategy
by consulting comparative results [14]. Specific
methodologies can be utilized to tackle problems in situations
where conventional optimization approaches may not be
appropriate, such as cases requiring discontinuous, nondifferentiable, stochastic, or very non-linear objective
functions.
In the next section, we will introduce a conceptual
framework for workload allocation, aiming to build upon the
foundational insights gleaned from the literature review. This
framework will encapsulate the cutting-edge strategies and
methodologies identified in recent research, tailored
specifically for optimizing workload allocation in WBANs
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and similar edge computing applications. Our focus will be on
addressing the challenges highlighted in previous studies and
proposing innovative solutions to enhance system
performance, efficiency, and user satisfaction.
III. A
TRI-PHASE APPROACH TO ENHANCING WBAN
EFFICIENCY
The proposed conceptual framework consists of three
phases to examine optimal workload allocation in edge-based
WBANs. These are designing the WBAN model, developing
the workload allocation algorithm, and carrying out
experimental evaluations.
Fig. 1. Fig 1: Overview of Methodology
A. Phase 1
As a first phase of research, simulate different WBANs
with a combination of different biomedical sensors using a
suitable network simulation tool. Real-world deployments of
WBANs can be expensive due to hardware, recruitment, and
ethical considerations involving human subjects. Therefore,
the phase 1 objective is designing WBANs to reflect realworld scenarios with different sensor sets and collect data on
sensor node transmission times to the edge processor through
simulations.
To simulate WBAN models, various simulation tools such
as PyLayer, Castalia, MoBAN, QualNet, Matlab, NS2, NS3,
OMNET, OMNET++, OPNET, etc can be used. This research
was chosen to be conducted with OMNET++ with the simple
programming language Python, due to its user-friendly
graphical user interface. Further, this tool supports modeling
any network, such as Wireless sensor network (WSN),
Software-Defined Networking (SDN), Ad-hoc, or Cellular
(4G, 5G, and Beyond5G (B5G) ), can be used with both
Ubuntu and Windows operating systems, and, most
importantly, can be used with simple programming languages
such as Python and C++ [15].
Different WBANs with different sets of biomedical
sensors would then be designed to simulate real-world
WBANs. Data transmitting time of each sensor node to the
edge processor can be collected using simulation design. The
characteristics of the proposed workload allocation method
will be evaluated with the different WBANs with a
combination of different biomedical sensors. Fig. 2 shows the
WBAN simulation design with the OMNET++ software.
Fig. 2. Fig 2: Simulating WBAN using OMNET++
Additionally, an online real-world data set will be used in
the simulation. datasets should be found from the original
sources or verify the data set validation with the original
sources. The majority of government institutes, agencies,
health departments, non-profit organizations, and educational
or research centers offer their data sets available for academic
use. In this research use electroencephalogram (EEG),
electrocardiogram (ECG), Blood pressure, Temperature, and
Oxygen saturation (SpO2) datasets for the simulation. But
with the different WBAN models, we can use different sets of
sensor data. These data sets processing utilizes a selected edge
processor and determines the data processing time required for
the algorithm's fitness function. This processing time is
different for different edge processors.
B. Phase 2
The second phase of this conceptual framework is to
develop optimal workload allocation algorithms to enhance
the system's quality. After successfully designing a WBAN,
different workload allocation algorithms would be applied to
find the optimum workload allocation algorithm for edgebased WBAN. Following a comprehensive review of the
relevant literature, the PSO method was selected to optimize
workload allocation in WBAN. Mainly considered their time
complexity ((), − number of iterations, − size of the
given data set, −dimension) and the performance. The
fitness function was designed for the PSO model by
considering the priority list of sensors. In the fitness
function,
added to add priority value to the sensors
according to the priority list. These priority values can be
changed according to the user requirements. With a few
changes, this fitness function can be used for different
applications.
Where n = number of sensors,
=
th
sensor’s
processing time +
th
sensor’s data transferring time,
=
th
sensor scanning count for collecting data,
= weight of
th
sensor
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C. Phase 3
Phase three of the conceptual framework is carrying out
experimental evaluations. The objective of the third phase is
to evaluate the performance of the workload allocation
algorithm across various WBAN configurations.
Experiments would be carried out to determine the
optimum workload allocation method that is independent of
the WBAN for each processing element. There are several
edge computing processors that can be used with WBANs,
such as NVIDIA Jetson Nano, Arduino Yun, Banana Pi M3,
Raspberry Pi, and ESP 32 [16]. In this part of the research, at
least two different processing elements (Raspberry Pi4 and
ESP 32) will be used. The Raspberry Pi4 and the ESP32 are
two of the most popular microcontrollers on the market that
can be used as edge processors. They are two small, lowpower consumption, low-cost microcontrollers with high
community support. Both processors can interface with other
systems to provide Wi-Fi and Bluetooth functionality through
their SPI / SDIO or I2C / UART interfaces [17]. The ESP32
however has a faster processor and more flash memory which
results in more power draw.
Fig. 3 depicts the fundamental experimental model utilized
in the research. Start by evaluating the network quality of the
system, focusing on the communication strength between the
edge node and cloud server. This process involves sending
data packets to the cloud and measuring the time it takes for
those packets to be received.
Fig. 3. Fig 3: Basic experiment model
Then update the data sending frequency of the algorithm
(frequency of data sending to the cloud from the edge node).
Next, execute the developed PSO algorithm on the edge
processor in order to optimize the allocation of workload.
Once the algorithm is implemented, the number of sensor
scans per transmission is updated to get the maximum benefit
from the system. Then the processed data is sent to the cloud
and end-user for storing and analyzing information that can be
utilized for disease monitoring, diagnosis, and therapy.
Next, evaluate the output and compare the efficiency of
the experimented algorithm with other algorithms or without
any optimization techniques. To accomplish this, power
consumption, and transmission failures of the system will be
measured, as illustrated in Fig. 3. This conceptual framework
and algorithm will optimize workload allocation in edge
processors by considering the network quality. Therefore,
with the developed conceptual framework, it would be
possible to update data sending frequency according to the
communication strength and scanning sensors maximum time
and collect data. Due to the optimum workload allocation,
system data transmission failures and power consumption will
be reduced.
IV. E
XPERIMENTAL RESULTS USING CONCEPTUAL
FRAMEWORKCONCLUSION
The proposed conceptual framework was tested and
validated through an experiment. For this research, we
selected the PSO method to optimize workload allocation in
edge-based WBAN after conducting a thorough review of the
relevant literature. The Raspberry Pi4 microcontroller serves
as an edge processor in this experiment. In this section, we
discussed the experimental results of the present conceptual
framework for optimal workload allocation in edge-based
WBANs.
This distribution has sample size 30, which is generally
considered large enough for the CLT to apply. For the power
consumption of PSO at 25-line quality value, data set
indicated a 95% confidence interval of 3.562 ± 0.0549. This
interval suggests that we can be 95% confident that the true
mean performance of the PSO algorithm lies within the range
of 3.5071 to 3.6169, demonstrating the algorithm's consistent
performance across the dataset.
As shown in Fig. 4, the experimental results are based on
the number of unsuccessful transmission attempts versus
network line quality. The experiment was carried out for both
workload allocation using the PSO algorithm and without any
optimization technique. The graphic shows that compared to
not using any optimization strategy, there are fewer
unsuccessful transmission attempts when the PSO algorithm
is applied.
Fig. 4. Fig 4: Unsuccessful data transmission attempts on each line quality
In both scenarios, the number of unsuccessful transmission
attempts increases as line quality decreases. However, the
graph shows that the number of unsuccessful transmission
attempts of workload allocation without any optimization
technique is almost twice the amount of unsuccessful
transmission attempts of workload allocation with PSO. This
is because workload allocation with PSO helps to reduce
unsuccessful transmission attempts due to the adaptation of
network line quality. Based on the line quality, the PSO
adjusts the sending frequency and the sensor scanning
frequency.
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Fig. 5. Fig 5: power consumption on each line quality
Fig. 5 presents the power consumption of the system for
different network quality with the PSO algorithm and without
any optimization technique. As observed from the figure there
is a higher power consumption for workload allocation
without any optimization technique. Since Raspberry pi4 uses
3.5 W to operate, there is an average 60% increase in extra
power consumption for workload allocation without any
optimization techniques than workload allocation using PSO.
Experimental results show that the employment of the
PSO algorithm enhances the quality of a system by reducing
unsuccessful data transmission and power consumption.
These findings pave the way for more resilient and energyefficient WBAN systems, with significant potential to
improve patient care and operational efficiency in healthcare
applications.
V. CONCLUSION
In this study, we have presented a conceptual framework
for optimizing workload allocation in edge device-based
WBAN. This research contributes to the body of knowledge
in the WBAN field by providing the optimal workload
allocation algorithm and experimental framework. It helps in
conducting experiments which are having high costs in realworld scenarios. The proposed method effectively increases
the WBAN system performance by reducing data
transmission failures and power consumption. In the future,
this framework will be used to experiment with different
optimization techniques and different edge processors. Also,
we intend to work toward a proactive workload allocation
algorithm that enhances the quality of the WBAN system.
Researchers may use this idea to develop new optimal
workload allocation methods to further improve the efficiency
of edge-based WBAN systems.
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