inventions

Technical Note An -Based Prototype for Data Security of Regulated Electricity Market

Aasim Ullah 1,* , S M Shahnewaz Siddiquee 2, Md Akbar Hossain 3 and Sayan Kumar Ray 3

1 School Engineering, and Mathematical Sciences, Auckland University of Technology, Auckland 1010, New Zealand 2 Department of Energy Engineering, University College Cork, College Rd, T12HY8E Cork, Ireland; [email protected] 3 School of Digital Technologies, Manukau Institute of Technology, Manukau 92068, New Zealand; [email protected] (M.A.H.); [email protected] (S.K.R.) * Correspondence: [email protected]; Tel.: +64-22439370

 Received: 22 September 2020; Accepted: 25 November 2020; Published: 27 November 2020 

Abstract: Data security of present-day power systems, such as the electricity market, has spurred global interest in both industry and academia. The electricity market can either be regulated (state-controlled entrance, policies, and pricing) or deregulated (open for competitors). While the security threats in a deregulated electricity market are commonly known and have been investigated for years, those in a regulated market still have scope for extensive research. Our current work focuses on exploring the data security of the regulated electricity market, and the regulated New Zealand Electricity Market (NZEM) has been considered for this research. Although the chances of cyberattacks on state-controlled regulated electricity market are relatively less, different layers of the current SCADA systems do pose some threats. In this context, we propose a decentralized Ethereum Blockchain-based end-to-end security prototype for a regulated electricity market such as the NZEM. This prototype aims to enhance data security between the different layers of the current SCADA systems. The detailed operation process and features of this prototype are presented in this work. The proposed prototype has prospects of offering improved data security solutions for the regulated electricity market.

Keywords: SCADA; blockchain; Ethereum; security; electricity market

1. Introduction The worldwide demand for electricity is expected to rise by 1.3% per year until 2040, primarily due to the effect of globalization [1]. This surge in demand has led to the interconnection of a wide range of distributed energy resources and electricity infrastructures, which are primarily the different electricity generation sites and the distribution channels. This inter-connectivity is commonly known as the Internet of Energy (IoE). The data generated from the various elements of IoE need to be managed securely as they are subject to hacking and cyberattacks, which include jamming, false data injection, and distributed denial-of-service attacks [2]. For example, a cyberattack on the U.S. grid in Western US created periodic blind spots at a grid control center and several small power generation sites for about 10 h on 5 March 2019. Contemporary power systems encountered remarkable advancement of data security in recent years. Contrary to traditional power systems, the NZEM is yet to adopt the advancement. One of the reasons is governing administration issues about company fixed revenues for line companies. There are distributed generation and several regional power suppliers in NZEM. Data security of the suppliers is an important term for any power market, and NZME is not an exception.

Inventions 2020, 5, 58; doi:10.3390/inventions5040058 www.mdpi.com/journal/inventions Inventions 2020, 5, 58 2 of 14

Supervisory Control and Data Acquisition (SCADA) systems are an integral part of the physical infrastructure of NZEM that monitors and stores real-time data of the grid network. A SCADA system is generally composed of a centralized control module and associated field level devices, i.e., sensors and actuators. The control module of SCADA provides a decision support platform that performs the related control task of the system. Given the dynamics of the SCADA system, the key features that make the SCADA system more susceptible to cyberattacks lie within its architecture and standard communication protocols. In many cases, the SCADA system adopts standardized technologies without enhancing the default security protocols. This practice can allow malicious agents to take over the SCADA system easily by exploiting the known vulnerabilities of the default security protocols. Subsequently, the usage of an unsecured network to connect multiple control modules also makes the system open for malicious attacks. Recently, most of the technical information about the specific SCADA control modules have been widely available as open-source content. This information, however, can be used to compromise the security of the entire SCADA system. Currently, there are many methods in place to reinforce SCADA network security that range from improved authentication for the user for access control, better firewalls, and intrusion detection system, protocol vulnerability assessment, and improved security for the connected devices and platforms . However, all the typical vulnerabilities are still being exploited by the adversaries utilizing improved malicious agents and approaches. An example of a cyberattack aiming at SCADA system vulnerabilities in recent years was the Ukrainian power outage in 2015. Blockchain technology, equipped with the key features of digital, chronological, time-stamped, distributed , consensus-based, and cryptographically sealed, is considered as a potential tool to provide the data security of the electricity market. The in blockchain can be used not only to enhance the speed and security of a smart grid [3] but also to prevent the retroactive alteration of data. Blockchain technology has immense prospects in better and secured streamlining of management of SCADA data transactions and peer-to-peer data transactions. The prospect of implementing blockchain technology for a regulated electricity market is investigated in this paper, and a decentralized end-to-end Ethereum Blockchain prototype is proposed to enhance the data security between the different layers of the current SCADA systems used in regulated electricity market like NZEM. In comparison to other existing blockchain protocols, Ethereum has more durability, which implies that it has reduced possibility of becoming obsolete since it stores data immutably. Its decentralized and distributed peer-to-peer data transaction is unique compared to other existing . Moreover, Ethereum’s smart contracts feature eradicates the demand for a third-party payment system. Moreover, it provides users with a platform and for building the applications. Therefore, in this work we have considered the Ethereum blockchain to address the following major research inquiries for a regulated market using SCADA system: (1) How can blockchain smart contracts support the state-owned regulated market? (2) How can blockchain safe-guard grid data for the communication level of the SCADA system which is sensitive to cyber-threat? (3) What are the prospective privacy and safety regulation for applying blockchain to NZEM? The remaining paper is structured as follows. While Section2 presents a review of the data security in power systems, the current status of data security in regulated and deregulated electricity markets is presented in Section3. Section4 discusses the decentralized Ethereum blockchain-based end-to-end data security prototype, and the paper concludes in Section5.

2. A Review of Data Security in Power System and introduction of Blockchain Data security in power system offers new prospects to maximize the energy performance of the power market. It provides the efficiency, and security for the fundamental detailed facilities of energy suppliers [4]. Modern cyber-security systems for power systems have turned complex and the cyberattacks are becoming smarter every day. The profound incorporation of cyberattacks can deliver false information to the control management facility team and eventually can result in system disorder, Inventions 2020, 5, 58 3 of 14

fiscal impairment, or critical consequences such as long hour’s blackouts. A current severe example of cyberattack was the 2015 Ukraine blackout [5]. False data injection attack refers to the manipulation of system data to trick away the control center without the flag service [6]. There are several studies [5,7] that exhibit the effect of False Data Injection Attacks (FDIA) on the modern grid system. However, in reality, grid security can be compromised not only by FDIAs but also by other forms of cyberattack namely denial of service (Dos), cyber topology attacks and data framing attacks [8,9]. Hence it is very essential to ensure the integrity and consistency of data to make the grid more secure and reliable. Several strategies have been suggested to identify and prevent cyberattacks depending on traditional centralized data communication and storage process [10]. Moreover, currently existing communication and measured meter data storage mechanisms are not fully protected against a cyberattacks. In some cases, even if the meters have been upgraded to PMU (phase measurement systems), they are still vulnerable to cyber-threats due to their dependency on global positioning system. Enhancing the self-defensive capabilities of modern power systems against cyberattacks requires the adoption of state-of-the-art innovations in distributed system security technologies. In this regard a modern distributed power system can be viewed as distributed advanced measurement infrastructure that includes distributed data acquisition, data monitoring, and storage on both grid side and demand side [11]. First, introduced in 2008, blockchain is designed to facilitate peer to peer electronic transactions directly without the involvement of a third party [12]. In blockchain, each peer works as a node to form a distributed network where they participate in estimating the solution to a hash-based mathematical problem to ensure the integrity of the transaction. Each time when a transaction is made, it is encapsulated in a block and added to the blockchain framework. The recorded block contents are called as ledgers, and all the information is updated synchronously to the entire network so that the record of the ledger is kept by each peer in the network. Since the advent of blockchain, technology has been mostly focused on the financial domain in the form of maintaining virtual , cross border payments and settlements, security issuance, and payments. The most prominent application of blockchain technology is the system, a framework which maintains a global for peer to peer transaction. Following the Bitcoin system, some companies, such as Etherium, , Ripple, Chain, , etc., have been set up in recent years. Among other works, the blockchain swarm system by Ferrer [13] and Sharples and Domingue [14] is mentionable and has good prospects to be implemented for power systems. Recently, there has been a shift observed in the energy market towards a distributed market structure [15] with increased number of prosumers and increase volume of data. In a centralized market structure, storing this large volume of data has higher costs, and the risk of compromising all data is very high under any cyberattack. It is also difficult for the market entity to access the previous data if they are stored in one organization under a centralized market. Hence, transparency issues also arise for the market operators. Addressing this problem, many authors have provided different techniques on adopting blockchain technology in the energy market to ensure better data security and market operation. In [16], a distributed blockchain based protection framework has been proposed to improve the data security by resisting external network attacks in a modern power system. This proposed framework utilizes distributed security features of the blockchain system and uses smart energy meter as node to keep the recorded power data with a distributed ledger which ensures the integrity and consistency of the data. In [17], a sovereign blockchain based smart grid management system is being proposed to protect the data of the consumers for ensuring the transparency and integrity of the data. It also protects the data from tampering under any cyberattack. This proposed system uses smart contacts to detect the grid operation and identify any malicious agents in the system. In [18] a distributed blockchain based power market trading platform is proposed to provide P2P secured transactions. In this blockchain based P2P transaction model, all the participating nodes and Inventions 2020, 5, 58 4 of 14 all transaction are stored. Since the data are stored in the blockchain and they are connected to all the nodes, they are more secure and transparent. The security risks for a deregulated electricity market are therefore recognized and well defined. The security threat for regulated market is obvious, unknown, and meaningful to investigate. In this paper, the proposed Ethereum blockchain network deals with data security features of the regulated market system indicated as follows: : The fundamental element of this Ethereum blockchain signifies the data confidentiality on a distributing system (for any kind of data capturing, recording, updating or storing). It discharges the data-dependency on central node, which has high data security risk. Transparency: In this work, the data script in each node written and updated transparently with trusted source in blockchain system. Open Sourcing: Ethereum Blockchain system is very public. All data tracking can be verified publicly, and people and new applications in the system are easy to create. It itself can transfer and store revenue like a retail outlet. A transaction concerning two parties can exchange the transaction details. Autonomous: Autonomy Chain Cloud of Ethereum Blockchain network controls the node by trusting a single head source for the entire system. The system ensures the data confidentiality so that no one can intercept it. Immutability: In the used system, the transaction records are saved permanently and cannot be modified without having control on at least more than half of the nodes simultaneously. Anonymity: Ethereum blockchain technologies solved the trust problem between node and node, so data transfer or even transaction can be anonymous, only needing to know the person’s blockchain address. Anonymousness: Ethereum blockchain system data transaction can be done anonymously. Knowing blockchain address suffice for any transaction.

3. Electricity Market and Data Security This section highlights the current status of the regulated and deregulated electricity markets, the use of blockchain-based transaction and security in the electricity market, and the state of NZEM. It also provides an overview of the potential cybersecurity issues in the current electricity markets.

3.1. Traditional Data Security Issues in Regulated and Deregulated Market In a regulated energy market like NZEM, a central control (utility company) is charged with electricity generation, distribution, and bidding. Hence the communication is restricted between the consumer’s smart meter and the utility company. Most of the time, in such a traditional regulated market, communication between the different electricity nodes happens through the use of traditional communication protocols and encryption protocols, which are highly vulnerable to security threats and malicious attacks. A data breach in a single node can compromise the whole market framework leading to a chain of catastrophic events. On the other hand, in a deregulated market, consumers can decide to purchase electricity from different retailers. Since many entities (e.g., retailers, operators, consumers, etc.) can participate in active trading in a deregulated market, these different market entities may require access to different data for different purpose [19]. For example, a grid operator may require access to short-term or long-term consumption data, location and personal information of the consumer, and power quality index data such as voltage and frequency data in order to maintain grid stability. Any breach in data security on this ecosystem can pose potential harm to consumers, retailers, and operators. Since in a deregulated market the consumer is trading with different retailer, a peer to peer secure transaction and data security model can be effective against potential cyber or malicious attacks. Leveraged with the concepts of peer-to-peer data sharing and safe transaction facility, the blockchain technology was initially utilized for fiscal security. The energy market started using this technology primarily for data trading and also for energy transmission and dispatch [3]. Traditionally, Inventions 2020, 5, 58 5 of 14 in a regulated energy market, utility companies own and operate the electricity. The tariffs of electricity are usually set and regulated by state commissions or regulatory boards. On the contrary, in a deregulated energy market, multiple competitors can buy electricity and sell it to the retail suppliers who then set different prices for the customers. The electricity service providers or competitors in a deregulated market form a cluster with their customers. It utilizes the decentralized blockchain Inventions 2020, 5, x FOR PEER REVIEW 5 of 14 technology to provide the security of the data flows from each customer to competitors in the cluster and from competitorsretail suppliers to thewho governmentthen set different entity. prices for Since the customers. it is a peer-to-peer The electricity service secured providers transaction or model, competitors docompetitors not have in a access deregulated to each market other’s form a cluster data. with their customers. It utilizes the decentralized blockchain technology to provide the security of the data flows from each customer to competitors in Figure1 showsthe cluster the and approach from competitors of transaction to the government in the traditional entity. Since blockchain-based it is a peer-to-peer transactionsecured model. As shown in thetransaction figure, model, a traditional competitors blockchaindo not have access is a to decentralized each other’s data. system that stores transaction data at each peer. DataFigure is stored1 shows in the a approach hub-based of transaction cloud system, in the traditional and the blockchain-based process can transaction then be executed by model. As shown in the figure, a traditional blockchain is a decentralized system that stores developing precisetransaction smart data contracts at each peer. for Data blockchain is stored in technology.a hub-based cloud Only system, the and authorized the process Government can then people can see differentbe executed competitor’s by developing data precise as shown smart incontracts Figure for1 ,blockchain but the competitorstechnology. Only themselves the authorized will not have access to other’sGovernment data. people can see different competitor’s data as shown in Figure 1, but the competitors themselves will not have access to other’s data.

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Figure 1. TraditionalFigure 1. Traditional Blockchain Blockchain based based transaction transaction model model for deregulated for deregulated market. market. Commented [M5]: The upper left of this picture is incomplete, please replace it with a picture that meets the 3.2. An Overview3.2. An of Overview NZEM of as NZEM a Regulated as a Regulated Electricty ElectrictyMarket Market requirements An electricity market is very much similar to any other market where products (in this case its An electricityelectricity) market are bought, is very sold, muchand traded similar in wholesale to any and other retail fashion. market The where electricity products market is thus (in this caseCommented its [AU6R5]: Figure replaced electricity) aredivided bought, into sold,generation, and transmission, traded in wholesaledistribution, and and retail. retail The fashion. wholesale Theof electricity electricity depends market is thus divided into generation,on power generation transmission, and connection distribution, to the grid andby the retail. transmission The wholesale company. It of also electricity facilitates depends on buying and selling of power between generators and re-sellers. The retail market is responsible to sell power generationit to end-users. and connection In NZEM, power to the generation grid by companies the transmission can bid to supply company. electricity Itat grid also injection facilitates buying and selling ofpoints power across between the country generators whereas there and tail companies re-sellers. bid Thefor the retail electricity market at grid is exit responsible points. to sell it to end-users. In NZEM,There powerare six principal generation power companies companies in NZEM can,bid namely, to supply Meridian, electricity Con-tact, Genesis, at grid Mighty injection points River, Trust Power, and Todd. Half of NZEM’s electricity generation is based on hydro power and across the countrythere are whereas geothermal, there wind tail farms, companies gas, biomass bid plants, for and the thermal electricity stations at as grid well. exitThe generated points. There arepower six is principal then trans-mitted power through companies the national in NZEM,power grid, namely, which is Meridian,owned, operated, Con-tact, and Genesis, Mighty River,maintained Trust Power, by the state and owned Todd. Transpower Half New of NZEM’sZealand. The electricity national grid generationhas nearly two ishundred based on hydro grid exit points (GXPs) throughout New Zealand, and these GXPs are the supply points for power and theredistribution are geothermal,networks. The line wind companies farms, distribu gas,te electricity biomass throughout plants, New and Zealand thermal by linking stations as well. The generated power is then trans-mitted through the national power grid, which is owned, operated, and maintained by the state owned Transpower New Zealand. The national grid has nearly two hundred grid exit points (GXPs) throughout New Zealand, and these GXPs are the supply points for distribution networks. The line companies distribute electricity throughout New Zealand by linking the national grid, and they also sell electricity to retailers. The details of the distribution companies in Inventions 2020, 5, 58 6 of 14

NZEM are publicly available just like other regulated market pricing and revenues. Re-tail companies in NZEM sell electricity to end-users. A list of energy retailers can be found in [20]. Retailers buy electricity at wholesale prices (contract and spot). The pricing and revenues for line companies in NZEM regulated market are fixed by the Commerce Commission. Residential users, industry buyers, and business clients all buy electricity from retail providers. As discussed in Section2, in a regulated market like NZEM where the entrance, policies, and pricing are state controlled, the data security threats are mostly in generation and transmission zones. On the contrary, for a deregulated market where distribution companies have no limit of revenue, the data security threat are mostly on the distribution retailer consumer zone. NZEM is a regulated market run by government bodies that keeps a check on the generation of revenues of suppliers. In such a regulated market, the entrance and price charges are entirely controlled by the government. Hence, for a model like NZEM, there are less data security threats to the information exchanged and shared between the suppliers. In recent years, like multiple other countries, New Zealand also upgraded its power system by incorporating different digital devices into the grid, turning it into a smart grid. The purpose of the smart grid deployment is to enhance the operational efficiency of the entire power system, including generation, transmission, distribution, and retail. In the smart grid, the different components of the power system can communicate with each other, and this makes the grid more “intelligent” in its overall operation. However, smart grids are more vulnerable to potential cyberattacks. The use of Supervisory Control and Data Acquisition (SCADA) system to manage smart grids makes it further vulnerable to cybersecurity threats. This is basically due to the integration of intelligent electronic devices, data concentrators, and other communication equipment. In general, cyber threats in a regulated grid infrastructure can be classified into four categories [21]: (i) Key-based attacks, (ii) Data-based attacks, (iii) Impersonation-based attacks, and (iv) Physical-based attacks. Each of these cyberattacks focuses on exploiting the features or protocols of specific entities in the grid to take control of the system. The traditional blockchain-based transaction model for the deregulated market (explained in Figure1) is not applicable to NZEM; rather a blockchain solution has more prospects if implemented for SCADA security as discussed in Section4.

4. An Ethereum Blockchain Based End-to-End Security Prototype In this section, an Ethereum blockchain prototype is presented to provide end-to-end security for the SCADA based regulated energy market. Hence, this section discusses the basic elements of a SCADA system and provides details about blockchain construction.

4.1. Overview of SCADA System SCADA is a system of software and hardware elements used to monitor and control the NZEM. SCADA consists of different modules for monitoring, gathering, and analyzing real time system data. Functional modules of SCADA include hardware for process monitoring and process control, data acquisition module, user interface, communication modules, and software platform. The process control system of SCADA basically consists of remote terminal units (RTU’s) and programmable logic controllers (PLC) that connect a series of sensors for real time monitoring and data collection. Remote terminal unit or RTUs is a microprocessor controlled electronic device, which interfaces physical objects (such as circuit breakers) in the power grid to a SCADA system. Figure2a illustrates the functional architecture of a SCADA system. In a high-level architecture, the functional components of SCADA can be described as below: Inventions 2020, 5, x FOR PEER REVIEW 7 of 14

(3) Communication Module: This can be wired or wireless and facilitates communication (through analog or discrete signals) between all the different functional modules using a predefined communication protocol. On a larger scale, a long-range communication module can utilize phone network, satellites, microwave, or cellular packet data.

Inventions(4) 2020Host, 5 Computer:, 58 It acts as the central monitoring and control point and also hosts the software7 of 14 platform to facilitate the monitoring and interaction.

(a)

(b)

FigureFigure 2.2.Prospective Prospective security security threat threat in ( ain) Supervisory (a) Supervisory Control Control and Data and Acquisition Data Acquisition (SCADA) (SCADA) network (networkb) Gateway (b)/ firewallGateway/firewall of internal of network. internal network.

4.2. SCADA(1) Operational Configuration Equipment: and Smart Operational RTU equipment of SCADA in a smart energy network perspective is the circuit breakers, which can be operated by actuators or relays. In this proposed blockchain prototype, the Smart RTUs in the physical layer of SCADA are (2) Local processors: These may have multiple inputs from instruments (e.g., programmable considered as nodes for a decentralized network. Using a cloud simulation environment, we show logic controller, remote control unit, intelligent electronic devices, etc.) and outputs to the operational the effectiveness of the proposed prototype in protecting the system from cyberattacks. In the equipment. They include PLC, RTUs, intelligent electronic devices, and automation controller for simulation, a cloud-based SCADA network is used to accumulate, broadcast, and store data in the monitoring and control. proposed prototype. Customized collection, transmission, and receival of signal data between the (3) Communication Module: This can be wired or wireless and facilitates communication communication and physical layer are done through the smart RTUs of SCADA. The communication (through analog or discrete signals) between all the different functional modules using a predefined path is linked through the RTU-nodes. Only authorized users, who have access to the communication protocol. On a larger scale, a long-range communication module can utilize phone communication, are able to certify the data acquisition and process for the reports or signaling of network, satellites, microwave, or cellular packet data. different process used in the production environment. Advanced metering infrastructure (AMI) (4) Host Computer: It acts as the central monitoring and control point and also hosts the software plays an important role in the proposed decentralized data security system. It is envisioned that AMI platform to facilitate the monitoring and interaction. should contain the following key features: 4.2. SCADA Configuration and Smart RTU In this proposed blockchain prototype, the Smart RTUs in the physical layer of SCADA are considered as nodes for a decentralized network. Using a cloud simulation environment, we show the effectiveness of the proposed prototype in protecting the system from cyberattacks. In the simulation, Inventions 2020, 5, 58 8 of 14 a cloud-based SCADA network is used to accumulate, broadcast, and store data in the proposed prototype. Customized collection, transmission, and receival of signal data between the communication and physical layer are done through the smart RTUs of SCADA. The communication path is linked through the RTU-nodes. Only authorized users, who have access to the communication, are able to certify the data acquisition and process for the reports or signaling of different process used in the production environment. Advanced metering infrastructure (AMI) plays an important role in the proposedInventions decentralized2020, 5, x FOR PEER data REVIEW security system. It is envisioned that AMI should contain the following8 of 14 key features: (1)(1) Individual Individual smart smart RTU RTU with with distinctive distinctive IP IP address, address, data data storage storage and and process process drive, drive, RAM, RAM, signalsignal sender–receiver sender–receiver device. device. All All RTUs RTUs of of the th samee same layer layer need need to to be be inter-channeled. inter-channeled. (2)(2) A A public–private public–private key key must must be be used used to to encrypt encrypt each each smart smart RTU. RTU. (3)(3) Accessibility Accessibility of of bidirectional bidirectional information information gateway gateway for for related related parties parties and and associated associated systems. systems. InIn the the following following subsection, subsection, we are we going are going to discuss to discuss an Ethereum an Ethereum blockchain blockchain prototype prototype to facilitate to anfacilitate end-to-end an end-to-end data protection. data protection. The proposed The prop Ethereumosed Ethereum blockchain blockchain has three has elements: three elements: (i) Block, (i) (ii)Block, Smart (ii) Contract, Smart Contract, and (iii) Miner.and (iii) Miner.

4.3.4.3. Block Block Construction Construction TheThe literal literal meaning meaning ofof blockchainblockchain is is chain chain of of blocks. blocks. A block A block is a iscontainer a container data datastructure, structure, which whichstores stores key keytransaction transaction information, information, like like day day and and time time of of transaction, amountamount ofof transaction, transaction, participantparticipant in transaction,in transaction, and and so on. so Internally,on. Internally the blocks, the blocks are linked are bylinked the cryptographic by the cryptographic and hashing and concepts.hashing Aconcepts. hash function A hash routes function random routes data random to meaningful data to meaningful preset sized preset data. In sized summary, data. In each summary, block iseach connected block withis connected one-way with (i.e., one-way data is irreversible) (i.e., data is hash irreversible) string-links hash and string-links the resultant and hash the valueresultant is dihashfferent value from is the different previous from hash the values. previous In hash the process, values. theIn the blocks process, are collision the blocks resistant, are collision which resistant, means thatwhich if any means transaction that if inany the transaction block is changed in the byblock an unauthorized is changed by entry, an unauthorized it invalidates entry, all hash it addressesinvalidates ofall the hash block addresses sequences of one the byblock one. sequences The communication one by one. amid The thecommunication client-nodes isamid routinely the client-nodes carried out is withoutroutinely individual carried intervention.out without indivi Figuredual3 shows intervention. the construction Figure of3 shows the chain the along construction with the of details the chain of thealong contents with ofthe block details connections. of the contents of block connections.

FigureFigure 3. 3.Construction Construction of of the the chain chain along along with with the the details details of of the the contents contents of of block block construction. construction. 4.4. Development of Ethereum Smart Contract 4.4. Development of Ethereum Smart Contract Smart contracts help a customer (or miner) to trade data of any value via a transparent, conflict-free systemSmart whilst contracts preventing help any a third-partycustomer (or access. miner) Initially, to trade a data single of ledger any value is off viaered a totransparent, the customer conflict- as a sourcefree system of trust fromwhilst blockchain, preventing and any data third-party exchange thenaccess. happens Initially, between a single nodes. ledger Smart is contracts offered areto the a collectioncustomer set as of a elaboratedsource of trust logic, from which blockchain, are developed and data in JavaScript exchange platform.then happens Protected between data nodes. are stored Smart contracts are a collection set of elaborated logic, which are developed in JavaScript platform. Protected data are stored in blockchain database and can be retrieved only by authorized users. Figure 4 shows the construction flowchart of Smart Contract and its interaction with a different layer of the SCADA system. The data monitoring is developed in Python Zerynth IDE environment [22], and the communication layer for smart RTUs is made with microchips of espressif [23]. Zerynth is designed to link the IoT platforms of smart RTU to cloud services. Figure 5 shows sample of a smart contract script developed for the local Ethereum node operation in blockchain. Verified smart contract data is then transferred to Rinkeby (refer to Figure 4), which is a platform of the Ethereum blockchain test network (test net) [24]. Rinkeby test net, in contrast to Ethereum main network (main net) is an authorized network. Inventions 2020, 5, x FOR PEER REVIEW 9 of 14

For the console panel, Web3-Ethereum JavaScript API is used in the project [25]. “Web3.js” is a selection of libraries that facilitates communication with local Ethereum node via IPC or HTTP Inventions 2020 5 connection. ,A, 58deploy file and script codes are developed using HD wallet provider and web3.9 ofThe 14 HD wallet, with a public/private key tree feature, represented a master node (Meta Mask). Meta Mask Inventions 2020, 5, x FOR PEER REVIEW 9 of 14 inis blockchaina crypto wallet database for blockchain, and can be retrievedwhich offers only a by risk-free authorized approach users. on Figure a unique4 shows decentralized the construction web flowchartplatformFor the to of linkconsole Smart up Contractto panel, blockchain-based Web3-Ethereum and its interaction programs JavaScript with [26]. a di APMoreover,fferentI is used layer Application in of the the project SCADA Binary [25]. system. Interface“Web3.js” The (ABI) data is a selectionmonitoringspecification of islibraries is developed used thatas in afacilitates Pythonstandard Zerynth communication approach IDE environmentto communicate with local [22 Ethereum], with and thecontracts communicationnode viain IPCthe Ethereumor layer HTTP for connection.smartenvironment. RTUs A is madedeploy with file microchipsand script codes of espressif are developed [23]. using HD wallet provider and web3. The HD wallet, with a public/private key tree feature, represented a master node (Meta Mask). Meta Mask is a crypto wallet for blockchain, which offers a risk-free approach on a unique decentralized web platform to link up to blockchain-based programs [26]. Moreover,RTU, Application Sensor Communication Binary Interface Layer (ABI) specificationServer operation: is used asReading a standard from the Blockchain approach to communicate with contracts in the Ethereum SCADA, environment. Communication Web3 HTML Docs Server Cloud, Data Collection Layer JS Asset Communication link RTU, Sensor Communication Layer Server operation:Reading from the Blockchain Data processing in SCADA, Transaction Energy Management Optimization Layer Metamask Rinkeby CommunicationModule Web3 HTML Docs Server Cloud, Data Collection Layer JS Asset Communication link Writing operation: on Blockchain by client

Figure 4. The Construction flowchartData ofprocessing Smart Contract. in Transaction Energy Management Optimization Layer Figure 4. The Construction flowchart of Smart Contract. MetamaskZerynth is designed to link theRinkeby IoT platforms of smartModule RTU to cloud services. Figure5 shows sampleimport of a streams smart contract script developed for the# Configuration local Ethereum file node operation in blockchain. Writing operation: on Blockchain by client Verified# Ethereum smart contract modules data is then transferred to Rinkebyimport config (refer to Figure4), which is a platform of from blockchain.ethereum import ethereum import math the Ethereumfrom blockchain.ethereum blockchain testimport networkrpc (test net) [24].import Rinkeby json test net, in contrast to Ethereum main network (main net) is an authorized network. import requests # WiFi drivers Figure 4. The Construction flowchart of Smart Contract. from espressif.esp32net import esp32wifi as net_driver # import Real-Time Clock module import# for ESP-8266 streams ##import Configuration rtc file ## Ethereumfrom broadcom.bcm43362 modules import bcm43362 as importimport configtimers fromnet_driver blockchain.ethereum import ethereum importt=timers.timer() math from# for blockchain.ethereumParticle Photon import rpc importt.start() json from wireless import wifi import requests # WiFi drivers def get_epoch(): from# SSL espressif.esp32net module for https import esp32wifi as net_driver # importuser_agent Real-Time = {"user-agent": Clock module "curl/7.56.0"} #import for ESP-8266 ssl #importreturn rtc ##to from read broadcom.bcm43362 from analogue sensor import bcm43362 as importint(json.loads(requests.get(" timers http://now.zerynth.com/", net_driverimport adc t=timers.timer()headers=user_agent).content)['now']['epoch']) # for Particle Photon t.start() from wireless import wifi Figure 5. A Smart contract script fordef localget_epoch(): Ethereum node operation. # SSL module for https user_agent = {"user-agent": "curl/7.56.0"} import ssl return 4.5. Data#to readTransaction from analogue Process sensor for Mining int(json.loads(requests.get("http://now.zerynth.com/", import adc headers=user_agent).content)['now']['epoch']) Ethereum is an electronic currency used for funds exchange in an encrypted system which does not depend on any legalized central banking system. The blockchain transaction system in Ethereum Figure 5. A Smart contract script for local Ethereum node operation. data framework as Figureonline 5.payment A Smart contractsystem isscript described for local in Ethereum this section. node operation. ForEthereum the console employs panel, public Web3-Ethereum keys to address JavaScript deposits and API send is used currency. in the projectThe public [25 ].keys “Web3.js” also track is 4.5. Data Transaction Process for Mining athe selection transaction of libraries details. thatIn Ethereum facilitates blockchain communication systems, with data local exchanges Ethereum or transactions node via IPC are or usually HTTP connection.unseenEthereum and Aanonymous. deploy is an electronic file andThe script currencysystem codes fixes used are the developedfor “tru fundst”s exchange usingissue in HD betweenin wallet an encrypted provider nodes withsystem and web3.its whichanonymity The does HD notwallet,feature. depend with Knowing on a public any legalizeda/ privateblockchain keycentra treeaddressl banking feature, provides system. represented the The transaction ablockchain master node details,transaction (Meta which Mask). system have Meta in two Ethereum Mask major is a datacryptosections: framework wallet for as blockchain, online payment which osystemffers a risk-freeis described approach in this on section. a unique decentralized web platform to linkEthereumPrincipal up to blockchain-based employsdata: It features public programs keys the details to address [26 ].of Moreover, transaction deposits Application and files, send records, currency. Binary dealing, Interface The public contract (ABI) keys specificationhistory, also track and theisbank used transaction clearing as a standard information. details. approach In Ethereum to communicate blockchain withsystems, contracts data exchanges in the Ethereum or transactions environment. are usually unseen and anonymous. The system fixes the “trust” issue in between nodes with its anonymity feature. Knowing a blockchain address provides the transaction details, which have two major sections: Principal data: It features the details of transaction files, records, dealing, contract history, and clearing information. Inventions 2020, 5, 58 10 of 14

4.5. Data Transaction Process for Mining Ethereum is an electronic currency used for funds exchange in an encrypted system which does not depend on any legalized central banking system. The blockchain transaction system in Ethereum data framework as online payment system is described in this section. Ethereum employs public keys to address deposits and send currency. The public keys also track the transaction details. In Ethereum blockchain systems, data exchanges or transactions are usually unseen and anonymous. The system fixes the “trust” issue in between nodes with its anonymity feature. Knowing a blockchain address provides the transaction details, which have two major sections:

InventionsPrincipal 2020, 5, x data FOR: PEER It features REVIEW the details of transaction files, records, dealing, contract history,10 of 14 and bank clearing information. Public data: Anyone can verify some transaction data at permitted level and can also participate in the process of getting consensus. As Ethereum Ethereum is a Public Public Blockchain, Blockchain, permitted transaction details will be public,public, and the systemsystem can be involvedinvolved in the progressionprogression of gettinggetting consensus. In Figure 66,, an Encrypted process in in active active RTU RTU nodes nodes during during tr transactionansaction with with public public and and private private key key details details is isshown. shown.

Transferred Transaction Storage Info #Hash RTU Node

Encrypt Data Signature RTU Node RTU Node Public Private Blocks Key Key

Consensus RTU Node

RTU Node RTU Node

RTU Node

Figure 6. Encryption process in active remote terminal unit (RTU) nodes during transaction.transaction.

The transaction procedure confirmsconfirms the computing potentiality to get hold of consensusconsensus and subsequently files files the the transaction transaction details details to to network. network. For For any any authorized authorized or unauthorized or unauthorized party, party, the theunique unique ID is ID kept is keptas necessitated. as necessitated. In Figure In Figure 7a, a Coinbase7a, a Coinbase account account for an forauthorized an authorized user is usershown. is shown.The user The can usersee the can transaction see the transaction details along details with along main with Ethereum main Ethereum network details network as detailsshown asin shownFigure in7b. Figure The 7Metamaskb. The Metamask Ropsten Ropsten Test Network Test Network and andits transaction its transaction details details are are shown shown in in Figure Figure 77c.. According toto thethe transactiontransaction operation,operation, therethere areare fourfour scenariosscenarios forfor transactiontransaction experienced:experienced:

- Old RTU node confirmsconfirms identityidentity andand sendssends detailsdetails toto newnew RTURTU node.node. - Old RTU node cannot confirmconfirm identityidentity andand failedfailed detailsdetails toto newnew RTURTU node.node. - New RTU node confirmsconfirms identityidentity andand sendssends detailsdetails toto oldold RTURTU node.node. - New RTU node cannot confirmconfirm identityidentity andand failedfailed detailsdetails toto oldold RTURTU node.node.

Ropsten Test Network Main Ethereum Network Deposit Ether X Account1 To interact with decentralized 0x0e2厖 ?f234 applications using MetaMask, user needs Account1 Ether in wallet 0x0e2厖 ? f234

3.234 ETH $0.00 USD Directly Deposit Ether If you already have some Ether, the 0ETH DEPOSIT SEND quickestwaytogetEtherinyournew wallet by direct deposit. $0.00 USD History #42-12/11/2020 at 21:20 -0.9 ETH VIEW ACCOUNT Contract Interaction DEPOSIT SEND CONFIRMED Details coinbase History From You have no transaction yet 0x77d50cb67638f40 > 0x77d50cb67638f40 Buy on Coinbase Transaction Coinbase is wolrd抯 most popular way to buy and sell Bitcoin, Ethereum and . Amount 0.9 ETH

(a) (b) (c)

Figure 7. (a) Coinbase account to see the transaction details. (b) Main Ethereum network details. (c) Analyzing transaction details in Metamask Ropsten Test Network. Inventions 2020, 5, x FOR PEER REVIEW 10 of 14

Public data: Anyone can verify some transaction data at permitted level and can also participate in the process of getting consensus. As Ethereum is a Public Blockchain, permitted transaction details will be public, and the system can be involved in the progression of getting consensus. In Figure 6, an Encrypted process in active RTU nodes during transaction with public and private key details is shown.

Transferred Transaction Storage Info #Hash RTU Node

Encrypt Data Signature RTU Node RTU Node Public Private Blocks Key Key

Consensus RTU Node

RTU Node RTU Node

RTU Node

Figure 6. Encryption process in active remote terminal unit (RTU) nodes during transaction.

The transaction procedure confirms the computing potentiality to get hold of consensus and subsequently files the transaction details to network. For any authorized or unauthorized party, the unique ID is kept as necessitated. In Figure 7a, a Coinbase account for an authorized user is shown. The user can see the transaction details along with main Ethereum network details as shown in Figure 7b. The Metamask Ropsten Test Network and its transaction details are shown in Figure 7c. According to the transaction operation, there are four scenarios for transaction experienced: - Old RTU node confirms identity and sends details to new RTU node. Inventions 2020,-5 , 58 Old RTU node cannot confirm identity and failed details to new RTU node. 11 of 14 - New RTU node confirms identity and sends details to old RTU node. - New RTU node cannot confirm identity and failed details to old RTU node.

Ropsten Test Network Inventions 2020, 5, x FOR PEER REVIEW 11 of 14 Main Ethereum Network Account1 0x0e2厖 ?f234 Account1 Commented [AU9]: Please check if this figure is OK. 0x0e2厖 ? f234

3.234 ETH $0.00 USD 0ETH DEPOSIT SEND $0.00 USD History #42-12/11/2020 at 21:20 -0.9 ETH Contract Interaction DEPOSIT SEND CONFIRMED Details History From You have no transaction yet 0x77d50cb67638f40 > 0x77d50cb67638f40 Commented [M7]: Garbled characters appear above the Transaction picture, please replace it with a picture that meets the Amount 0.9 ETH requirements (a) (b) (c) Commented [AU8R7]: Not clear. Did you mean the Star Figure 7. (a)Figure Coinbase 7. (a) Coinbase account account to seeto see the the transactiontransaction details. details. (b) Main ( bEthereum) Main network Ethereum details. network (c) details. Analyzing transaction details in Metamask Ropsten Test Network. sign on top of Figure 7(a)? this is bookmark sign of the (c) Analyzing transaction details in Metamask Ropsten Test Network. platform. 4.6. Miner Status 4.6. Miner Status In blockchain technology, blocks are formed, and their content verified by miners, who compete between themselves in the process (so-called mining) of appending new blocks to the blockchain. In blockchainThis subsection technology, examines blocks the miner are status formed, based andon different their power content data verified of different by nodes miners, of smart who compete between themselvesRTUs as shown in the in processFigure 8. (so-calledEtherscan, which mining) is a block of appendinganalytics as well new as a blocks block manager to the blockchain. decentralized smart contracts platform for Ethereum, is used for this purpose. Ethers examine and This subsectionbrowse examines the Ethereum the minerplatform status for transaction based ondetails diff likeerent encrypted power data, data block of dinumber,fferent miner nodes of smart RTUs as shownaddress, in currency Figure 8details,. Etherscan, etc. (refer to whichFigure 9). is The a Meta block Mask analytics wallet uses as the well storing as keys a block (like manager decentralizedEther smart and contractsERC20 tokens) platform for the Ethereum for Ethereum, platform is[27]. used Samples for of this transactions purpose. added Ethers to the examine and Rinkeby server are shown in Figure 9a, in which the access is given to the miner only. browse the EthereumThe monitoring platform status for transactionof the application details layer likeof the encrypted SCADA system data, is indicated block number, by the status miner address, currency details,OUT. etc.Moreover, (refer Figure to Figure 9b shows9). the The detailed Meta analys Maskis of wallet the transaction uses the in which storing the miner keys sends (like Ether and ERC20 tokens)thefor request the for Ethereum transactions platform to the Rinkeby [27 server.]. Samples The hash of and transactions miner address details added can to be the derived Rinkeby server from the Rinkeby server address. The integer Ether values and transaction fees show the Ether are shown inbalance Figure used9a, for in the which individual the accesstransaction. is given to the miner only.

Figure 8. Chosen power data of different nodes of smart RTUs. Figure 8. Chosen power data of different nodes of smart RTUs. Commented [M10]: The upper left of this picture is incomplete, please replace it with a picture that meets the The monitoringFigure status 8 shows of the the power application data of different layer companies of the SCADAand Figure system 9 examines is indicatedthe associated by the status transaction details for the same. It is found that peer-to-peer data transaction is secured through hash requirements OUT. Moreover,transaction. Figure Any9b showsunauthorized the detailed party can analysisjust view the of transaction the transaction as hashed in message which but the cannot miner sends the Commented [AU11R10]: It was just an arrow mark. OK request for transactionsretain the original to the values Rinkeby or written server. text. It The is evident hash from and the miner miner address status that details the addresses can be are derived from removed. the Rinkeby serverunique address.and can be Theaccessed integer only by Ether permitted values parties. and Moreover, transaction peer-to-peer fees show data transaction the Ether of balance used Figure 9b shows that the Rinkby server addresses for all five power data of the three different for the individual transaction. Inventions 2020, 5, 58 12 of 14 Inventions 2020, 5, x FOR PEER REVIEW 12 of 14

(a)

(b)

Figure 9. (a(a) )Transaction Transaction added added in in the the Rinkeby Rinkeby server. server. (b) ( bInspecting) Inspecting the the smart-contract smart-contract balance balance on Etherscan.on Etherscan.

5. ConclusionsFigure8 shows the power data of di fferent companies and Figure9 examines the associated transaction details for the same. It is found that peer-to-peer data transaction is secured through hash This paper proposes a decentralized Ethereum blockchain-based safety prototype for better data transaction. Any unauthorized party can just view the transaction as hashed message but cannot security of the regulated power market. The proposed prototype considerably promotes self- retain the original values or written text. It is evident from the miner status that the addresses are defensive functionality against cyber-attack and is an advancement towards data safety in power unique and can be accessed only by permitted parties. Moreover, peer-to-peer data transaction of systems. Substantial technical discussions in the context of the existing power systems are Figure9b shows that the Rinkby server addresses for all five power data of the three di fferent companies highlighted in this paper. The transaction performed is used to address the above-mentioned issue. are unique. Therefore, any unauthorized entry has no chance of false data injection through the One way the proposed system is protecting the data from energy market from manipulation or RTUs/Rinkeby address. fraud is utilizing the immutability characteristic of the blockchain framework. The proposed system uses5. Conclusions ledgers to store the data and each block of the data is stored using a unique hash value. This feature ensures that the data stored cannot be manipulated by an external entity. Moreover, the proposedThis paperframework proposes is adecentralized, decentralized Ethereumwhich makes blockchain-based it impossible safety for prototypean external for betterentity data to compromisesecurity of the the regulated market data power us market.ing cyberattack The proposed such as prototype DDoS. considerably promotes self-defensive functionality against cyber-attack and is an advancement towards data safety in power systems. Inventions 2020, 5, 58 13 of 14

Substantial technical discussions in the context of the existing power systems are highlighted in this paper. The transaction performed is used to address the above-mentioned issue. One way the proposed system is protecting the data from energy market from manipulation or fraud is utilizing the immutability characteristic of the blockchain framework. The proposed system uses ledgers to store the data and each block of the data is stored using a unique hash value. This feature ensures that the data stored cannot be manipulated by an external entity. Moreover, the proposed framework is decentralized, which makes it impossible for an external entity to compromise the market data using cyberattack such as DDoS.

Author Contributions: Conceptualization, analysis, methodology, and experiments, A.U.,; manuscript preparation, A.U., S.M.S.S., and M.A.H.; data curation, A.U., writing—review and editing, A.U., S.M.S.S., M.A.H., and S.K.R. All authors have read and agreed to the published version of the manuscript. Funding: The research received no external funding. Conflicts of Interest: The authors declare no conflict of interest.

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