Query: Blockchain process modeling

title: The Role of Modeling in Blockchain Process Design
abstract: Blockchain could introduce a new approach by which organizations view and govern their information and technology projects. Processes involving blockchain are oftentimes transaction based, decentralized, and require coordinated communization before implementation. This approach may introduce new challenges to conventional modeling techniques. In this study, the role of modeling during the design phase of blockchain processes is explored. This role is described through a theory derived from 30 semi structured interviews, two case studies, and two focus groups. The results are applied to inter organizational business process modeling. The role of modeling, the effects on this role caused by the introduction of blockchain, and the shortcomings of current modeling techniques are described. Additionally, the study provides several opportunities for future research.

title: Decentralized Business Process Modeling and Instance Tracking Secured by a Blockchain
abstract: For supporting the conceptualization and the management of enterprise models in a decentralized manner, this paper introduces an approach based on model versioning and blockchain technologies. The main contribution is twofold, consisting of a. the creation of models for inter organizational business processes in a decentralized environment, and b. means for tracking process instances using meta data at run time. Models for business processes, workflows, and instance states are collaboratively created as part of a decentralized architecture. Based on this approach, a hierarchical versioning and modeling approach is employed in order to create and manage public and private models in a transactional fashion. For forming relationships among decentralized participants, semi formal models linked to a blockchain are suggested. The approach is evaluated with a supply chain use case and demonstrated in an implemented modeling tool.

title: Modeling and Enforcing Blockchain Based Choreographies
abstract: Distributed Ledger Technology (DLT) and blockchains in particular have been identified as promising foundations to realize inter organizational business processes. Capabilities such as shared data and decision logic defined as smart contracts open up entirely new ways to implement process choreographies. However, current choreography modeling languages solely focus on direct interactions between organizations; they do not take into account the conceptually new features of blockchains, like shared data and smart contracts. To bridge the gap between choreography modeling and implementation, this paper critically analyzes the assumptions of choreography languages. We propose new language concepts specifically targeting blockchain capabilities, and we define their operational semantics. Our work is evaluated with a proof of concept implementation and an analysis of three real world case studies from the private and the corporate sectors.

title: Modeling and execution of blockchain aware business processes
abstract: The blockchain is an emerging technology that allows multiple parties to agree on a common state without the need for trusted intermediaries. Moreover, business process technology streamlines the automation of inter and intra organizational processes while cutting down on costs. With the new business opportunities provided by blockchains, it becomes vital to combine both technologies to allow the modeling and execution of blockchain based interactions within business processes. However, the existing business process modeling languages lack support to intuitively model the various interactions with blockchains. In this paper we address this issue by proposing a business process modeling extension that captures the particularities of blockchains. We also show how to transform the proposed constructs into standard compliant models, and we present an integration architecture that allows external applications, to communicate with the blockchains. Finally, we validate our approach by providing a prototypical implementation that proves its practical feasibility.

title: Performance Modeling of PBFT Consensus Process for Permissioned Blockchain Network (Hyperledger Fabric)
abstract: While Blockchain network brings tremendous benefits, there are concerns whether their performance would match up with the mainstream IT systems. This paper aims to investigate whether the consensus process using Practical Byzantine Fault Tolerance (PBFT) could be a performance bottleneck for networks with a large number of peers. We model the PBFT consensus process using Stochastic Reward Nets (SRN) to compute the mean time to complete consensus for networks up to 100 peers. We create a blockchain network using IBM Bluemix service, running a production grade IoT application and use the data to parameterize and validate our models. We also conduct sensitivity analysis over a variety of system parameters and examine the performance of larger networks

title: An Empirical Study on Modeling and Prediction of Bitcoin Prices With Bayesian Neural Networks Based on Blockchain Information
abstract: Bitcoin has recently attracted considerable attention in the fields of economics, cryptography, and computer science due to its inherent nature of combining encryption technology and monetary units. This paper reveals the effect of Bayesian neural networks (BNNs) by analyzing the time series of Bitcoin process. We also select the most relevant features from Blockchain information that is deeply involved in Bitcoin's supply and demand and use them to train models to improve the predictive performance of the latest Bitcoin pricing process. We conduct the empirical study that compares the Bayesian neural network with other linear and non linear benchmark models on modeling and predicting the Bitcoin process. Our empirical studies show that BNN performs well in predicting Bitcoin price time series and explaining the high volatility of the recent Bitcoin price.

title: Performance Modeling of Hyperledger Fabric (Permissioned Blockchain Network)
abstract: Hyperledger Fabric (HLF) is an open source implementation of a distributed ledger platform for running smart contracts in a modular architecture. In this paper, we present a performance model of Hyperledger Fabric v1.0+ using Stochastic Reward Nets (SRN) From our detailed model, we can compute the throughput, utilization and mean queue length at each peer and critical processing stages within a peer. To validate our model, we setup an HLF network in our lab and run workload using Hyperledger Caliper. From our analysis results, we find that time to complete the endorsement process is significantly affected by the number of peers and policies such as AND The performance bottleneck of the ordering service and ledger write can be mitigated using a larger block size, albeit with an increase in latency. For the committing peer, the transaction validation check (using Validation System Chaincode (VSCC) is a time consuming step, but its performance impact can be easily mitigated since it can be parallelized. However, its performance is critical, since it absorbs the shock of bursty block arrivals. We also analyze various what if scenarios, such as peers processing transactions in a pipeline, and multiple endorsers per organization.

title: Application of Integrated Building Information Modeling, IoT and Blockchain Technologies in System Design of a Smart Building
abstract: AEC) industry has not adopted digital transformation enthusiastically like other industries, for instance, manufacturing, aerospace or finance. Building Information Modeling (BIM) is an innovative technology that is considered as an opportunity for the AEC industry to move to the digital era and improve the collaboration among stakeholders by applying Information and Communication Technologies (ICT) BIM provides all required tools and automations to achieve end to end communication, data exchange and information sharing among collaborators. Accordingly, virtual 3D models, created by the BIM process, delivered as physical assets, monitored in real time and managed using Building Management Systems (BMS) can adopt the Internet of Things (IoT) designs and services. However, the implementation of IoT in a highly modular environment with various moving parts and inter dependencies between stakeholders leads to security concerns. Therefore, this paper proposes system design that employs the blockchain technology as a measure to secure and control the framework that involves integrated IoT and BIM technologies. Although this paper considers system design applied in a smart museum, the authors assume that design is generic and applicable in other building categories. For instance, this design can be implemented in the ongoing Alumni Hall renovation project at State University of New York College at Oneonta.

title: Performance Modeling of the Consensus Mechanism in a Permissioned Blockchain
abstract: We consider a permissioned blockchain and analyze the dissemination and commitment processes of blocks among its corresponding miner nodes in the underlying peer to peer network. We propose a Markovian non purging (n, k) fork join queueing model to analyze the delay performance of the synchronization process among these miner nodes that apply a vote based consensus procedure. We determine the impact of the most influential design and load parameters on the resulting commitment delay of new blocks that are appended to the blockchain after successful commitment decisions and the approval by the fully distributed consensus procedure. The proposed analysis of a permissioned blockchain is illustrated by means of a simple example of a fully interconnected P2P graph applying mean value analysis techniques.

title: Svitlana Filipova Modeling Business Processes on a Blockchain Ecosystem using CMMN
abstract: Blockchain has been speculated to be "the most important invention since the Internet" and has the potential to deliver significant business value for both financial and non financial industries. That is why companies have started to explore how their business processes can benefit from this technology. However, a simple substitution of a current process with new technology will not provide desired outcomes. For this purpose, process redesign is used where process models are made the basis of process analysis and its innovation. This paper examines how blockchain oriented processes can be modelled with CMMN as it is an artefactcentric modelling language. Such an approach might be particularly useful while modeling blockchainoriented processes as the fundamental focus of blockchain is on data that is added on a chain and shared between participants. This paper is based on a case study of a non profit organization providing certification services for companies trading timber relates products. The auditing process of this organization was redesign using blockchain and smart contract technologies and then was modelled with CMMN. For analysis of the suitability of CMMN for modelling blockchain based processes a framework for commonly occurring patterns that are specific to blockchain based applications was used. As a result, CMMN can adequately represent blockchain oriented processes. However, there is a lack of elements in the notation to accurately model certain details specific to blockchain and smart contract technologies.