Blockchain-based Intelligent Monitored Security System for Detection of Replication Attack in the Wireless Healthcare Network

— Wireless sensor networks have revolutionized the way healthcare works replacing the traditional methods with sensor-enabled IoT devices that help in monitoring the data. The data is collected by these sensors that are there on the body of the user, the data is transmitted over the network to the healthcare monitoring systems. The transmission follows the route of the wireless channel that is not secure as it can be accessed by legitimate as well as illegitimate users. These pose security threats; one such attack is a replication attack. This makes the replicas of the original node, replaces the data with the malicious content for attacking the system, and deploys the node back to the network making it difficult to detect. The aim of the work is to review the Blockchain-based intelligent monitored security system for the detection of replication attacks in the wireless healthcare network. The method used for review is the secondary research method. The main focus of the work is kept on the literature review for obtaining insights and knowledge. The results show that blockchain provides the required security to the data carried by the sensor-enabled IoT. The result contributed to the understanding of the different blockchain techniques in securing data. The system component is farmed in the work and verified in the results.

I. INTRODUCTION 1 Wireless healthcare networks have revolutionized the way the healthcare sector is monitored replacing the traditional method for efficiently operating the patient's health [1]. As every technology comes with certain drawbacks along with benefits, the open-access nature of the network makes it vulnerable [2]. The unauthorized access behavior and open-end threats can pose security concerns to the patient's healthcare data. The data collected by the wearable devices for healthcare monitoring have security issues. One of the most challenging attacks is the replication attack [3]. This attack is on the sensor node carrying the sensitive healthcare data of the patient, the attacks replace the sensor nodes with replicas of the sensor Submitted  nodes and replace the original data with fake data and deploys the sensor node back in the database [4].
Wireless healthcare systems are approachable to all the people around the globe, and this has reached every corner of the world [5]. The open-access nature of the technology of wireless healthcare networks and its wireless channels makes the transmission through the network unsecured [6]. The main aim of the work is to review the blockchain-based intelligent monitored security system for the detection of replication attacks in the wireless healthcare network. Blockchain is one of the most promising technologies for providing security [7]. Blockchain is known to provide a double layer of authentication and security to the data using cryptographic techniques and tools [8]. The data of the healthcare monitoring systems is observed and thus, detects such attacks on the wireless network of the healthcare monitoring system [8].
The work is structured as follows: Section II is a literature review that provides the overall understanding of the topic. The main focus of the work is centric on the review. The literature review explains the field of research, and the review is structured in different heading to provide the complete coverage of the topic. The system component table is included following the review. This states the common instances with the help of components and attributes for an overall view of the work. Section III explains the methodologies used for the work. Section IV; classification table, is also included. Section V is evaluation table. Section VI is system architecture. Section VII is the results and key findings of the work. Furthermore, Section VIII is discussion and Section IX is the conclusion that includes the major finding.

A. Field of Research
The research is made in the area of blockchain technology. The technology blockchain is evolving day by day with newer advancements. Blockchain technology provides security to the data using the cryptographic hash functions. The review is classified under different literature review headings. These explain the process from start to end and establish the knowledge in a hierarchal structure. The focus is made on blockchain technology in eliminating the replication attacks for securing healthcare data. Different models and techniques are discussed for this in the review. The research gap is stated at the end of the review and different instances and attributes along with factors are placed in the component table.

1) Wireless healthcare network and its security concerns
The Internet of Things (IoT) has advanced over time. IoT is considered to be the most prominent platform as it is dynamically used in resource sharing and helps in interconnecting different systems altogether. Reference [9] shows that one of the technical advancements of IoT can be seen in wireless healthcare networks. The platform connects different sensor nodes that monitors a patient's health and transfer the data through the network to the healthcare systems. The authors state that wireless healthcare has benefited many across the globe, however; the open nature of wireless channels makes them vulnerable to security threats. These threats are targeted at the sensitive data of the patient [10]. This makes the users question the integrity of the technology. The attackers can misuse the data or sell it further to a third party. As this data is sensitive, this needs to be protected [11].
The advancement of wireless healthcare data has uplifted and upgraded the traditional way of healthcare monitoring. Reference [17] shows that, after the COVID 19 outbreak in recent years, this technique is used all around the world to fight against the pandemic. The authors explain that wireless healthcare monitoring systems are facing security issues. The threat of data confidentiality is surfacing as the data is facing a privacy leak [18]. This becomes one of the major challenges that the wireless healthcare system is facing. Attacks like DDoS, network conjunction, and many more overload the server with unwanted data to access the legitimate data [54]. This needs to be solved in order to get the proper aid to every person.

2) Threats associated with replication attack on WHN
There are many attacks that interrupt the secure data flow in the transmission of the data through the sensors of the wireless Healthcare Network (WHN). Reference [15] shows that out of many attacks of replication attack, the attacks on the CT scan and image processing is one of the major ones. These attacks block the server and manipulate the image processing systems. As stated by the author this makes it hard for the system to process. These attacks hamper the process of the healthcare monitoring systems and data carried by the system for processing [14]. These attacks need to be addressed to properly and securely proceed with the analysis of the data [13].
A replication attack is the kind of attack that replaces the original node with the fake node carrying the data that can attack the database and manipulates the entire database. Reference [18] shows that one of the most prominent attacks is the replication attack. It is hard to detect the source, as the node carries the same identify as the original one and pose as the legitimate one. It is further stated by the authors, that the node is efficiently deployed back in the data after changing the original data with the fake data [17]. The node carrying the personal and sensitive data of the user is exposed to multiple threats due to the open-access nature of the wireless channels [13].

3) Blockchain-based intelligent monitored security system
The outbreak of the pandemic of COIVD-19 has affected the medical services industry differently. The spread of COIVD-19 has been disturbing to the worldwide medical services industry, as this is one of its sorts of pandemics that are seen by the world to date. Reference [63] shows that this caused medical services to understand the issue with the keeping up of the information and maintaining it. As the quantity of patients is expanding step by step till today, the issue that the medical care industry is facing is the upkeep security of the information [14]. Blockchain is one of the emerging technologies that have the potential of maintaining security in the database [19]. Blockchain is known for providing the desired security layer with the implementation of cryptography along with securing the data [19].
Digital data is targeted with many attacks. Reference [20] shows that the data scavenging attack in the resource for monitoring carrying data faces data leak issues because of the attack. As the system needs security, the authors explain that the issues while sending the data and receiving can be solved using blockchain technology. Blockchain technology is proposed to overcome the security challenges in order to secure the data and its privacy [21]. Blockchain is known to be providing a dual layer of authenticity to the system using the cryptographic hash functions [22], [23]. Blockchain works on the principle of encrypting and decrypting for providing security to the system [24], [15].

4) Blockchain technology in replication attack detection
The pandemic recently has shaken the entire world. The outbreak of COVID-19 has alarmed the healthcare monitoring systems around the globe. Reference [25] shows that the pandemic has made every country revisit its healthcare monitoring infrastructure. The authors explain the healthcare system needs to keep a close tab on the patients suffering from the same. The vulnerabilities in the system make it a taking point. The databases lack in providing security to the system and ultimately the unauthorized can access the data [20]. Blockchain technology has made it easier for the monitoring system in providing security to the healthcare system [12], [19]. Blockchain is among the technology that eliminates the risks associated with unauthorized access [5]. Blockchain can easily detect attacks using the encryption technique. Blockchain provides security from end to end [12], [10].
The advancement of the IoT has made the healthcare monitoring system easier as compared to the traditional methods. The data is collected using the sensor-enabled IoT and transmits data through wireless channels. Reference [21] shows that the open-access behavior of the wireless sensor networks has made the system vulnerable to attacks. A replication attack is one of the kinds of attacks that target the node carrying the data [29], [18]. The node carrying the data is replaced with the malicious node that is replicated and poses the same as the original node. The node is deployed back in the message and poses the same as the original. The author stated that the issue can be solved using the blockchain-based privacy-preserving scheme. This scheme realized the secure sharing of the medical data among the entities suing the zero-knowledge proof. Blockchain provides dual security to the data for security [3], [26].
The revolution of the internet of things has helped to transform any object into network data with the help of WSN [2], [27]. This has provided the platform for many applications such as smart grids, smart homes, and smart cities [25], [28]. One of the major implementations of IoT is in healthcare monitoring. Reference [17] explains that these sensor-enabled pose certain threats in privacy leakage during the handling process of data. These issues have been addressed using the M-PPKS. This approach is based on homomorphic encryption that ensures that the privacy of the user is maintained and there is no leakage of data. This enhances mutual privacy in the healthcare system. Blockchain technology uses encryption and decryption techniques to ensure the security of the data in the database [29]- [31]. The security of the system is a must as it carries sensitive data relating to the patient [32], [34].

5) Secured wireless healthcare networks using blockchain technology
Blockchain has gained attention all around the world because of its characteristics of undeniable nature and the benefits and security it provides to the database. [35] explain that the limitations faced by the internet of things can be solved using blockchain technologies. Blockchain has the ability to provide security to wearable devices in healthcare systems. Blockchain has a higher bandwidth overhead, higher computation complexities, latency, and restricted scalability, these factors can't be directly inherited in IoT [34], [36]. The authors discussed the ELIB model that is specifically made to fulfill the requirements of the IoT constrained. The blockchain ensures the complete security of the database and provides security to the data [37], [34].
The advent of blockchain technology has been revolutionary in recent years. Blockchain technology provides a secure platform for data. Blockchain enables data protection and detects anomalies in the system. Reference [35] explains that blockchain implementation secures healthcare services in the prediction of diseases in fog computing. Cardiovascular and diabetics are the disease that can be predicted by monitoring the health records collected with the help of healthcare wearables [66], [52]. The patient's data is collected using the fog nodes and stored in a blockchain database. The clustering techniques are applied to the data collected. The data is sent further for the healthcare monitoring system to consider the data and act upon it. Blockchain provides a dual layer of security to the database [40], [47]. Implementation of blockchain in healthcare systems is very helpful [33], [46].
The modernizations of the healthcare sector have provided room for the implementation of the internet of things and applications based on healthcare systems [45], [23]. Reference [47] shows that the modification of healthcare monitoring has provided the users' various benefits. The sensor-enabled devices help in monitoring the patient's health. The data is collected by the wearables and transmitted to the healthcare system. The wireless channels used for the transmission of the data pose security threats in the data; this can be solved using blockchain technology [45], [8], [26]. Blockchain technology uses a cryptographic hash function in providing the necessary security to the data [43], [14]. The blockchain implementations have bought significant impacts in providing security, enabling encryption techniques [1], [47].

C. Research Gap
The authors explained the implementation of the blockchainbased intelligent monitoring system for securing the wireless healthcare network from replication attacks. Many authors have explored the aspects of replication attacks on healthcare systems and the effective use of blockchain in providing security to the database. However, the authors didn't discuss the problems associated with the implementation of blockchain in the healthcare system. Blockchain implementation requires higher computational resources and is not that cost-effective.

D. System Component
Components of the system in general terms are described as the fundamental factors that are used to describe the overall process of the system. This work aimed to review blockchainbased intelligent systems for the detection of replication attacks in wireless healthcare networks. To get the insights and understanding of the work, 12 articles were selected that were reviewed in the work. The common components are selected in the work.
The component tables discuss the common instances based on the attributes from the selected 12 papers. The same is discussed in Table I. The system component table is based on the simple steps of input-process-output-evaluation. The factors, attributes, and instances are selected from the selected research articles after deep analysis of the research articles. The factors such as healthcare data, blockchain-based monitoring, attack detection, and attacks are the process steps that are input, process, output, and evaluation. The attributes such as healthcare dataset, data capturing devices, the framework used, techniques, and more. The instances are searched in the selected articles and then filled in the table to provide overall understanding.

III. METHODOLOGIES
The methodologies are the process that is defined before the beginning of the work. The methodology is a process of defining the process, belief, and rules for the completion of work. The methodologies include the process of data collection, the method in which the data will be organized and analyzed. The work is based on the review, the methodologies are chosen appropriately. The data is collected with the help of the CSU library. The keywords that best defined the topic were chosen at the beginning of the work. The keywords such as blockchain, healthcare monitoring, replication attack, security in wireless sensor networks, and many more that best suited the topic. The filters were restricted to the year 2020-2021 and the respected technology for selecting the 30 papers initially. Among the 30 Q1 selected papers, best 12 were selected for the review.
The research method used for the review is the secondary research method. The secondary research method collects the data from secondary sources such as research papers and journal articles related to the topic selected. The data is collected from secondary sources. The data is cited in the entire work along with the year of publishing. The research articles selected are published and provided a good source for the research work.

VII. RESULTS
The review of Blockchain-based intelligent monitoring system for detection of replication attack in the wireless healthcare network. The results from the work are as follows: The advancement of the internet of things has revolutionized the way healthcare works these days. Reference [48] explained that wireless healthcare networks have provided a platform to connect different sensor nodes to the healthcare monitoring system for efficiently monitoring the patient's data. Blockchain has bought various advancements, applicability, and authorization in the field of technology. Blockchain has various benefits one of which is providing security to the system and data. Reference [35] explains that blockchain technology has made it easier and reliable for healthcare systems especially monitoring systems in providing security to the healthcare system The system component table that was proposed in the research work is based on the overall understanding of the articles that were initially selected for the review. The system component explains the insights and understanding about the process steps that are input-process-output-evaluation. Based on these process steps the factors-attributes, and the instances are defined in the system component table. The system component table can be verified with the help of the percentage graph and theoretical description of the term frequency used in the work. The verification of the system component with the help of system verification, explains the terms that are used in the work with the help of the percentage of the terms used. The general understanding behind this is to state the usefulness of the system component and verify whether it is useful or not. The terms selected are from the instances and attributes of the system component table. It states the completeness of the work, as how many authors have used the term. The more the percent the more effective is the system component table. This process cannot be achieved using any software or any specific tool as this is completely based on context-dependency, this masked it difficult to automate the process, refer to Fig. 1. For example, the term data is used by 80% of authors to state the input in the system and 75% of authors stated the term healthcare dataset.  . This  depicts the theoretical analysis of the system component table,  refer to Table IV. The most frequently used terms are selected from the system component. The terms are thoroughly checked in the selected 12 articles for the analysis of the terms selected. The frequency of the terms is stated in the table. The higher the frequency the more effective the system component table. The frequency here refers to the appearance of the term in the paper.

VIII. DISCUSSION
The work explains the review of blockchain-based intelligent monitoring systems for the detection of replication attacks in wireless healthcare networks. Based on the work of the authors that were initially selected, the system component table and system classification table are prepared that define the factors, attributes, and instances of the work of different authors. The component table explains the important factors related to the topic. The factors were selected such that they explain the inputprocessing-evaluation-output of the work.

A. Healthcare Data
The factors such as healthcare data that is a factor that states the datasets used in the work, the second attribute is data capturing devices that explain the devices that are used in healthcare monitoring that is a source of input in the system, the framework used in other attributes that define the input step.

B. Blockchain-based Monitoring
Blockchain-based monitoring is the factor that sates the processing step of the system. The attributes such as techniques, algorithms, tools, models, systems, and network attributes. These attributes are used for the processing of the work. The instances define the different approaches by the authors.

C. Attack Detection
The next factor is attack detection that explains the evaluation step that is the attributes of this factor explain the different approaches used for the evaluation such as the attributes are attack types, data type, and blockchain-based detection outcomes.

D. Evaluation
The last step is the evaluation that states the outcomes of the work, the attribute in the evaluation is performance parameters that explain the outcomes of each of the works of authors after the completion of the process.
System classification tables explain each of the instances that are defined in the component table corresponding to the authors. The classification table explains the components stated in the component tables as per the literacy work of the authors. The information provided in the component table helps in understanding the different attributes that are used in the work. The component table provides an overview of the different techniques, algorithms, frameworks, tools, and other parameters and components that are used for the detection of replication-based attacks in the healthcare system. The blockchain techniques and algorithms along with other parameters can be viewed in one place. The work of the authors can be analyzed with the help of the classification table.

IX. CONCLUSION
Wireless sensor networks have gained a lot of attention from various sectors for implementing the technology for the betterment of the sector. One such sector is the healthcare sector. The implementations of wireless sensor networks have eased down the monitoring of healthcare systems. The open nature of wireless channels makes the system vulnerable to threats. These threats pose security issues related to the privacy and confidentiality of the data. Replication attacks make replicas of the node, infuse them with the malicious data and deploy them in the network in place of the original node. Replication attacks go undetected because of their properties. This issue is solved using blockchain-based monitoring systems. The aim of the work was to review the Blockchainbased intelligent monitoring system for the detection of replication attacks in the wireless healthcare network. Blockchain technology brings various advantages to the data and system. Blockchain provides security to the data and eliminates such risks and threats. The proposed system component is verified graphically and theoretically. Through the above-held review, it can be concluded that a blockchainbased intelligent monitoring system can be used for the detection of replication attacks in wireless healthcare networks as it provides security to the data and the system. The technology in the future can be used in other domains as well for security and privacy challenges.