Transaction Flow Research Articles

Bitcoin miners: Exploring a covert community in the Bitcoin ecosystem

In the Bitcoin ecosystem, bitcoin miners play an indispensable role in maintaining the Bitcoin’s blockchain. As a consequence, they are also rewarded with newly-created bitcoins and transaction fees. However, there are very limited studies to fully understand the characteristics and behaviors of bitcoin miners. In this paper, we conduct a comprehensive measurement study to shed insights into the community of bitcoin miners. By analyzing over ten-year bitcoin transaction logs, we observe that the scale of bitcoin miners shrinks significantly in recent years, and a small fraction of miners received most of newly generated bitcoins. In the early stage of the Bitcoin ecosystem, the mining reward was evenly distributed among miners, but later became more concentrated to a few highly active miners. For most of miners, their active duration is less than one year, and the interval between consecutive mining actions is more than 100 days. By further examining the transaction flows, we find that a significant portion of bitcoins have been hoarded for over 5 years, and the hoarding phenomenon becomes intense in recent years. We also discuss the implications of our findings, and believe our measurements enable us to have a better understanding of the whole Bitcoin ecosystem.

Smart University Library Management System Based on Internet of Things

With the innovation of new technologies, many life concepts have been changed. However, libraries remain the same in many sides while the main role of libraries has been changed and new references may not need a classical library as it was 50 years ago. In the same time, library services can be improved using Internet of Things (IoT) to increase user satisfactions. In recent years, there has been arisen in the diversity of implementation based on radio-frequency identification (RFID) systems and has been successfully utilized in several areas such as health care and transportation. RFID-based library management system will let rapid transaction flow for the library and could prove instant and long-term benefits to library in traceability and security. To solve the problem that it is inconvenient to find references in the traditional library, a kind of reference positioning system using RFID technology is designed to achieve fast search references in the library. Searching and sorting misplaced references are a hard task often carried out by the librarians. In this paper, the performance of RFID reader motion and tags allows fast transaction flow and easily handling the process like references borrowing from library can be done using RFID technology and users will get notified using Global System for Mobile. Two big issues have been exposed and tried to find the best solution for them, first is the management process of any library, from user management to shelving system and the second one is the data and reference security. The results show that the system can quickly find the references that bookworms hid, and the references are not timely put back on the shelves. Furthermore, the new library hall design and IoT-based system improve the security.

ANALISIS EFISIENSI PENERAPAN TRANSAKSI NON TUNAI DALAM PENGELOLAAN KEUANGAN DAERAH PADA SEKRETARIAT DAERAH KOTA METRO PROVINSI LAMPUNG

Implementation of non-cash transactions in each region are different, both constraints and applications. The non-cash transaction system is considered to be more practical, efficient, easy, even able to support the economy through increased money circulation speed. The implementation of this non-cash system is one of the forms to realize the financial management that is transparent, accountable, effective and efficient. The aim of this study is empirically to know the efficiency of the implementation of non-cash transactions in regional financial management at Metro District. The research method used is a quantitative descriptive method. The results showed that the implementation of the non-cash transactions in regional financial management at Metro City, Lampung Province provides many benefits namely transactions become highly efficient and also effective. The advantage of implementing a non-cash transaction system is that the use of all transaction flows can be traced so that it is more accountable because all transactions are backed by valid proof; treasurer does not have to hold cash with varying risks of crime, loss and error counts; avoiding financial abuse in regional devices; more efficient usage of budgets and more controlled cash-in flows; improve internal control of cash management and simplify billing acceptance. In addition, non-cash transactions tend to be more cost-effective when compared to the use of cash transactions with kartal money, banknotes or coins and accelerate the implementation of book close as well as financial reporting and guaranteed reliability.Keywords: Efficiency, Non-Cash Transactions

SISTEM PELAYANAN BANTUAN MENTOR BIMBINGAN BELAJAR (BAMBIMBEL) BERBASIS WEB

Adanya tuntutan penerimaan mahasiswa baru dengan menggunakan ujian Seleksi Nasional Perguruan Tinggi Negeri (SNMPTN) di Indonesia, siswa lulusan SMA/SMK diharapkan menguasai beberapa mata pelajaran dasar. Berdasarkan data primer wawancara penjurusan siswa yang dilakukan SMA/SMK di Indonesia belum cukup untuk membekali siswa dalam persiapan mengikuti ujian seleksi nasional, layanan bimbingan belajar didominasi jumlah terbanyak di kota besar, kemudian mahalnya biaya bimbingan belajar membuat siswa sulit punya kesempatan untuk mengikuti bimbingan belajar sehingga perlu dirancang sistem pelayanan bimbingan belajar yang dapat diikuti oleh siswa tanpa dibatasi ruang dan waktu. Salah satunya adalah sistem bimbingan belajar berbasis web. Bimbingan belajar termasuk salah satu Pendidikan non-formal. Pasal 1 angka 12 Undang-Undang Nomor 20 Tahun 2003 tentang Sistem Pendidikan Nasional menyatakan pendidikan non-formal adalah jalur pendidikan di luar pendidikan formal yang dapat dilaksanakan secara terstruktur dan berjenjang. Tujuan dari penelitian ini adalah merancang dan menghasilkan sebuah sistem pelayanan bantuan mentor bimbingan belajar (BAMBIMBEL). BAMBIMBEL juga memfasilitasi siswa yang ingin belajar untuk persiapan seleksi perguruan tinggi negeri. Metode yang digunakan adalah metode perancangan sistem berbasis web dengan pemodelan Unified Modeling Language (UML), pengujian sistem menggunakan metode Black Box, berdasarkan pengujian yang diamati dapat disimpulkan hasil eksekusi melalui data uji dan fungsionalitas dari sistem BAMBIMBEL berjalan dengan baik dan sesuai dengan yang diharapkan

Adaptive Model for Credit Card Fraud Detection

<p>While the flow of banking transactions is increasing, the risk of credit card fraud is becoming greater particularly with the technological revolution that we know, fraudulent are improve and always find new methods to deal with the preventive measures that financial systems set up. Several studies have proposed predictive models for credit card fraud detection based on different machine learning techniques. In this paper, we present an adaptive approach to credit card fraud detection that exploits the performance of the techniques that have given high level of accuracy and consider the type of transaction and the client's profile. Our proposition is a multi-level framework, which encompasses the banking security aspect, the customer profile and the profile of the transaction itself.</p>

Information Technology in The Activities of Service Enterprises

The article discusses the process of informatization in the system of activity of service enterprises. The essence of the definition of informatization in the service sector is revealed. The article describes the experience of using an operating level system that supports management operations, monitors elementary actions of an organization such as sales, payments, cash deposits, payroll. The main goal of the system at this level is to answer common questions and conduct transaction flows through the organization. The article indicates that the reform of the methods of managing facilities in the service sector entailed not only a reorganization of the organization of the process of automation of managerial activities, but also the spread of new forms of implementation of this activity.

Performance modeling and analysis of a Hyperledger-based system using GSPN

As a highly scalable permissioned blockchain platform, Hyperledger Fabric supports a wide range of industry use cases ranging from governance to finance. In this paper, we propose a model to analyze the performance of a Hyperledger-based system by using Generalized Stochastic Petri Nets (GSPN). This model decomposes a transaction flow into multiple phases and provides a simulation-based approach to obtain the system latency and throughput with a specific arrival rate. Based on this model, we analyze the impact of different configurations of ordering service on system performance to find out the bottleneck. Moreover, a mathematical configuration selection approach is proposed to determine the best configuration which can maximize the system throughput. Finally, extensive experiments are performed on a real-time system to validate the proposed model and approaches.

Critical Study of Criminal Aspects of Law Number 8 of 1999 Concerning Consumer Protection

Globalization and free trade supported by advances in telecommunications and information technology have expanded the space for the flow of transactions of goods and / or services across national borders, so that the goods and / or services offered vary both in foreign production and production domestic. Such conditions on the one hand have benefits for consumers because consumers' needs for the desired goods and / or services can be met as well as increasingly wide-open freedom to choose various types and quality of goods and / or services in accordance with the wishes and abilities of consumers. The conditions and phenomena can cause the position of businesses and consumers to become unbalanced and consumers are in a weak position. In our daily lives we hear, read and even witness various business practices that are detrimental to consumers. Business practices that are detrimental to consumers are not only carried out by large-scale business actors, but also by medium-sized businesses and small business actors. Violations of consumer rights committed by business actors constitute a potential threat to the welfare of society, due to increased activity of business actors in the production and trade of goods and / or services to meet consumer needs if not monitored and weak law enforcement, consumers will be severely disadvantaged. For this reason, we need to understand the subject of legal protection to consumers through the explanation of Law No. 8 of 1999 concerning Consumer Protection (UUPK), including a study of criminal aspects.

Secured Energy Trading Using Byzantine-Based Blockchain Consensus

To mitigate the problems of demand-supply mismatch in the future grid the solution of renewable energy source (RES) integration results in a bidirectional flow of information and transactions, which are prone to different kinds of cyber attacks, especially in energy trading where the security of financial transactions is of most concern. Electric vehicle (EV) having the advantage of mobility can play a significant role in maintaining demand-supply balance at any location unlike their peers (conventional compensator). For deciding entire system security, securing EVs charging-discharging transactions at all charging stations or connecting points is most important. The system can be made more secure against cyber-attacks with the introduction of the blockchain framework. Hence, in view of secured transactions, the paper focuses on the energy trading process between EVs and distribution network (DN) in a Byzantine based blockchain consensus framework. During peak load period DN initiates the energy trading process by demanding additional power from the EVs. This process of energy trading results in energy and information exchange which needs to be secured through blockchain from vulnerable attacks and threats. Possible scenarios of various cyber-attacks on different nodes of the system are visualized in the form of false data. To highlight the application of blockchain, the Byzantine general problem framework is used which states that for successful attack 33% of information is to be manipulated, in other words, decreasing the probability of attack confirms the system security. Numerical results based on various operating scenarios for the standard IEEE 33 bus system are in agreement with the Byzantine consensus problem indicating improvement in system security.

EC-ElGamal and Genetic Algorithm-Based Enhancement for Lightweight Scalable Blockchain in IoT Domain

Security, data privacy and decentralization are significant challenges in the Internet of Things (IoT) domain. These challenges are inherited attribute of another emerging technology, Blockchain. This enforced convergence of IoT and Blockchain, attracting researchers to study on the effective use of Blockchain’s strength to solve the challenges of IoT. Rapid IoT adoption requires standardization and mature solution on security, data protection for compliance and performance for commercialization. These demands made a surge in variant blockchain flavours and combinations catering to different problems, and one such is Lightweight Scalable Blockchain (LSB). LSB had considerable caveats that require improvement for better adoption in the IoT domain. This paper focuses on encrypting transaction transmission, improving transaction flow, block validation, hash quality, hash rate and storage cost to improvise security and performance. The experimental evaluation is demonstrated on data from the temperature sensor to showcase superior applicability of the proposed work in the IoT domain. Implementation and result comparison with conventional LSB proves, the following achievements 1) An additional layer of transaction encryption using hybrid Elliptic Curve ElGamal (EC-ElGamal) method increases the security of the transmitted transaction for security enhancement. 2) Obtained 20% reduction in transaction processing time, 22% reduction on block validation processing time, 53% improvement on the hash operation and quality with an overall 7% saving on the storage cost thereby increased the overall performance.

An Optimization Model for Transaction Placement in Blockchain Shards

Abstract Sharding technology can be used to improve the scalability of a blockchain system. The suitable placement of transactions into shards can reduce cross-shard ones, so as to improve system throughput and reduce delay. An optimization model for transaction placement to blockchain shards is proposed. Based on time analysis and a transaction flow graph, the fitness is computed to decide which shard is the most suitable one to place a transaction. The experimental results show that the proposed model can effectively reduce cross-shard transactions and reduce transaction delay.

Cipherchain: A Secure and Efficient Ciphertext Blockchain via mPECK

Most existing blockchain schemes are based on the design concept “openness and transparency” to realize data security, which usually require transaction data to be presented in the form of plaintext. However, it inevitably brings the issues with respect to data privacy and operating performance. In this paper, we proposed a novel blockchain scheme called Cipherchain, which can process and maintain transaction data in the form of ciphertext while the characteristics of immutability and auditability are guaranteed. Specifically in our scheme, transactions can be encrypted locally based on a searchable encryption scheme called multi-user public key encryption with conjunctive keyword search (mPECK), and can be accessed by multiple specific participants after appended to the globally consistent distributed ledger. By introducing execution-consensus-update paradigm of transaction flow, Cipherchain cannot only make it possible for transaction data to exist in the form of ciphertext, but also guarantee the overall system performance not greatly affected by cryptographic operations and other local execution work. In addition, Cipherchain is a promising scheme to realize the technology combination of “blockchain+cloud computing” and “permissioned blockchain+public blockchain”.

A Blockchain-Assisted Trust Access Authentication System for Solid

The Solid (Social Linked Data) project focuses on data sharing and privacy security and aims to build a decentralized ecosystem that radically changes the way web applications work today. Our goal is to introduce a “trust access authentication system” to achieve secure authentication and fine-grained access control, thereby promoting the implementation of Solid. Blockchain, equipped with multiple security properties and authentication functions, is a crucial technology. In this paper, we present a blockchain-assisted system for secure authentication in Solid and for implementation of fine-grained access control policies. Specifically, we explore to integrate threshold RSA signatures in a permissioned blockchain system to enable a fault-tolerant distributed signature scheme, thereby enhancing the resilience and robustness of authentication system. Moreover, we utilize smart contract to control transaction flows and manage access control policies automatically. Experimental results show that our proposed trust access authentication system enhances security, scales well, and is efficient and economically feasible.

Research on modeling of electric power transaction process based on block chain technology

Block chain technology is one of the optional technologies for the realization of intelligent power transactions on the residential side, and the specific transaction process is lacking research. Based on the composition of the block chain and its technical characteristics, this paper proposes a typical transaction flow for market participants in the electricity transaction under the environment of the residential side open electricity market based on block chain technology. According to the needs of power trading, the power trading using block chain technology is divided into 7 steps and abstracted separately. Finally, the power transaction based on block chain technology is analyzed, and the transaction process is further explained in combination with the case, which provides a reference for the introduction of new technologies for the design of ubiquitous power internet of things power transactions.

АНАЛІЗ ЗАСТОСУВАННЯ ІНСТРУМЕНТІВ РИНКОВОГО ПРОФІЛЮ ТА МЕТОДИКИ СКАЛЬПІНГА У ВНУТРІШНЬОДЕННІЙ ТОРГІВЛІ Ф’ЮЧЕРСНИМИ КОНТРАКТАМИ.

The article discusses the tools of the theory of market profile used to analyze the distribution of exchange volumes, as well as the principles of practical application of the analysis of the flow of orders and scalping elements. This paper proposes its own intraday trading strategy based on the assumption that the traders have open unprofitable positions on the market based on data from the report on changes in the open interest of the Chicago Mercantile Exchange and their identification using non-standard application of market profile and scalping tools, which makes it possible to adopt effective trading decisions. Using the tools for analyzing the volume of transactions of market auction participants - the levels of the value area, we identified the zones of possible concentration of open unprofitable positions, which in the future can be massively closed, creating a price impulse. Using scalping tools - Level I and Level II (the flow of transactions and market depth), changes in the nature of the dynamics of the flow of orders of participants in a market auction were analyzed. The strategy was tested on real stock data of a futures contract on the E-mini S&P 500 stock index by real-time testing. The test results confirm the assumption that there is a constant presence of open unprofitable positions in the market, since transactions based on the search for concentration zones of these positions were made against the direction of the price trend, which moves the market to identified zones. The massive closure of unprofitable positions, later confirmed by orders of bidders, turned out to be able to unfold the current market intraday trend, which makes it possible to make effective trading decisions and in the future increase trade capital. The use of exchange volume analysis tools in trading has proven to be very effective and can complement any intraday techniques, increasing profitability and lowering risk indicators in trading. The test results showed a critical effect of commission costs on intraday trading methods, which can significantly reduce the profitability indicator up to a loss-making strategy result

Identifying suspicious addresses in Bitcoin thefts

Bitcoin as a popular digital currency has been a target of theft and other illegal activities. Key to the forensic investigation is to identify bitcoin addresses involved in the bitcoin transfers. This paper presents a framework, FABT, for forensic analysis of bitcoin transactions by identifying suspicious bitcoin addresses. It formalizes the clues of a given case as transaction patterns defined over a comprehensive set of features. FABT converts the bitcoin transaction data into a formal model, called Bitcoin Transaction Net (BTN). The traverse of all bitcoin transactions in the order of their occurrences is captured by the firing sequence of all transitions in the BTN. When analyzing transaction flows, FABT exploits the notion of “bitcoin fluid” to track where the bitcoins passed through given addresses (called dyeing addresses) have flown and determine the extent to which each of the other addresses is related to the dyeing addresses. The splitting, merging, and dyeing operators are used to capture the distribution of coins throughout transaction flows. FABT also applies visualization techniques for further analysis of the suspicious addresses. We have applied FABT to identify suspicious addresses in the Mt.Gox case. A subgroup of the suspicious addresses has been found to share many characteristics about the received/transferred amount, number of transactions, and time intervals.

Financial Variables, Market Transactions, and Expectations as Functions of Risk

This paper develops methods and a framework of financial market theory. We model financial markets as a system of agents which perform market transactions with other agents under the action of numerous expectations. Agents’ expectations are formed of economic and financial variables, market transactions, the expectations of other agents, and other factors that impact financial markets. We use the risk ratings of agents as their coordinates and approximate a description of financial variables, market transactions, and expectations of numerous separate agents by density functions of aggregated agents in the economic domain. The motion of separate agents in the economic domain due to a change of agents’ risk rating produces collective financial flows of variables, transactions, and expectations. We derive equations on collective financial variables, market transactions, expectations, and their flows in the economic domain. These flows define the evolution of financial markets. As an example, we present a simple model with linear dependence between disturbances of volume and the cost of transactions on one hand, and disturbances of expectations that determine transactions on the other hand. Our model describes harmonique oscillations of these disturbances with numerous frequencies and allows an explicit form for fluctuations of price and return to be derived. These relations show a direct dependence between price, return, and volume perturbations.

Blockchain Empowered Wireless Power Transfer for Green and Secure Internet of Things

Wireless power transfer is a promising approach to charge low-power IoT devices for energy replenishment. However, energy attacks from malicious IoT devices can result in significant energy loss to energy transmitters. In this article, we propose a new distributed and secure wireless power transfer architecture by utilizing blockchain. The proposed architecture includes two planes: the energy plane and blockchain plane. We further abstract three types of traffic flows, transaction flow, consensus flow and coin flow, to provide a profound insight into the workflow of blockchain. Furthermore, to obtain the optimal amount of transferred energy in the energy plane, and to resolve high operational overhead of the consensus process in the blockchain plane, we develop a contract theory based wireless power transfer scheme and a DPoS based lightweight consensus scheme, and design an efficient wireless power transfer mechanism by combining the two schemes. Illustrative results demonstrate that our proposed schemes offer significant energy loss reduction with moderate operational overhead.

Rules Assurance: Preventing Unauthorized Access through Building Right Firewall Configuration

Any business organization’s backbone is their infrastructure which establishes the connection between their own intranet, vendor/customer network and external world. Network is linked between these network are through dedicated connection or public connection via internet. To build any network, it requires servers, firewalls, routers, core and access switches with communication link. The topology of network, link type, usage of network devices are chosen based on organization need and type of data transaction flows between these networks. Considering volume of data growth because of digital revolution, sensitiveness of data like Personally Identifiable Information (PII) or Protected Health information (PHI), it is necessary to protect data from hackers and save network from phishing, malware or ransomeware. Firewall will control the access and decides what to allow or deny between networks. These rules are defined in firewall Access Control List (ACL). A strong, well matured access control policy plays a key role to ensure network security and data protection. A firewall rule defines inbound and outbound data traffic between source and destination. These sources and destinations are identified by IP addresses, subnet ranges, protocols, applications, and port numbers. ACL defines what can be accessed / denied from internal (OUT BOUND) or from external (IN BOUND). In general a firewall has hundreds of ACLs and at times in thousands as well. Since frequent changes are inevitable, managing firewall rules becomes a complex task. There is no relationship between these rules and need not be in an order. Firewall will not validate duplicate or overlapping of rules. Every rule in ACL is independent and there are more possibilities of having obsolete and invalid rules. To overcome all these complexities, this wok presents rules mining, which helps to analyze firewall rules, identify security flaws, vulnerabilities from existing rules and eliminate redundant or unused rules from network. This paper proposes a new guidelines that can be used on existing firewall ACL or while building new firewall ACL to protect network from external sources. These guidelines will help network administrators to fix configuration errors.

Classification of position management strategies at the order-book level and their influences on future market-price formation.

Financial prices fluctuate as a results of the market impact of the flow of transactions between traders. Reciprocally, several studies of market microstructure have shown how decisions of individual traders or banks, implemented in their trading strategies, are affected by historical market information. However, little is known about the detailed processes of how such trading strategies at the micro level recursively affect future market information at the macro level. Using a special fined-grained dataset that allows us to track the complete trading behavior of specific banks in a U.S. dollar (USD) versus Japanese yen (JPY) market, we find that position management methods, defined as the number of units of USD bought or sold by banks against JPY, can be classified into two strategies: (1) banks increase their positions by trading in the same direction repeatedly, or (2) banks attempt to reduce their inventories by rapidly shifting their positions toward zero. We then demonstrate that their systematic position management strategies strongly influence future market prices, as demonstrated by our ability using this information to predict market prices about fifteen minutes in advance. Further, by detecting outlier trades, we reveal that traders seem to switch their strategies when they become aware of outlier trades. The evidence obtained here suggests that positions, which are a consequence of historical trading decisions based on the position management strategies of each bank, strongly influence future market prices, and we unravel how market prices at the macro level evolve through an interactive process involving the interaction between well-defined trading strategies at the micro level.