CryptoBIM: Blockchain-Enabled and Cryptographic Building Information Modeling
Project Team
Martin Fischer, Michael Lepech, Hesam Hamledari
Overview
Existing BIM solutions provide the users with information regarding the latest status of a project; however, an immutable, secure, and accurate record of changes, updates, and decisions is needed. The lack of such records hampers the documentation of contributions by various team members, and it limits the potential uses of project data as input to AI techniques.
We propose the integration of blockchain technology and BIM as a solution to the lack of such immutable records.
Blockchain-enabled and cryptographic building information modeling (CryptoBIM) is introduced as a solution to this problem; CryptoBIM generates an immutable and cryptographically secure record of decisions throughout a project’s life cycle; it is a first step toward the adoption of blockchain technology in the AEC industry, and it can potentially enable applications such as smart contracts and decentralized autonomous organizations.
Project Background
Research Motivation
Lack of an immutable record of changes, updates, and decisions. Using BIM, project members can observe the latest status of a project’s model. This model, however, is the result of thousands of modeling decisions, numerous contributions from project members, and multiple interactions with software that push data to BIM. Current BIM solutions do not provide an immutable and secure record of such changes, updates, and decisions; as a result, it is hard to understand who did what and at what point in time.
Limited input for artificial intelligence (AI)-based and data mining application. Because the records of decisions and changes do not exist, the applicability of AI-based solutions on project data is limited. For example, applying AI and data mining techniques to past project/modeling records can help us more clearly understand the future outcomes of modeling decisions, the project group dynamics, best modeling practices, and patterns of failure among projects. The increasing interest in the integration of sensor data and internet of things (IoT) applications with BIM further necessitates the use of AI and data mining for extracting actionable insights.
Data privacy/ownership. Models, or information about BIM elements, cannot be seamlessly shared due to concerns regarding data privacy and ownership. This poses challenges for collaborations among trades and project members. BIM technology does not allow secure and selective data sharing, and the identities of project members and modelers are not securely documented.
Lack of a mechanism for documenting contributions. A solution is needed to generated a temporal and detailed documentation of the contributions by various project members and also by software that push data to BIM. This provides incentives for project members, but it can also help identify the sources of problems. Such documentation of contributions and the identities of contributors needs to be secure and only available to authorized individuals.
Blockchain technology and cryptography have been proven to address similar limitations in the world of finance, giving rise to the rapidly growing financial technology (Fintech); this proposal aims to explore the use of blockchain to address the discussed limitations and evaluate its effectiveness, challenges, and impacts on the engineering problem.
Research Objectives
The integration of BIM with blockchain technology has not been previously addressed, and it can act a first step toward the adoption of blockchain in the AEC industry. This project will introduce a secure means of generating the immutable distributed ledger for BIM.
With this respect, various issues need to be explored. First, the type and the format of the data stored on the blockchain needs to be identified. Second, a mechanism should be designed to allow members to build reputation while protecting their identity. Further, the extent of the on- and off-chain storage of data should be studied; not all project information needs to be directly stored on the blockchain and in the blocks. Data on the distributed ledger will be shared among various users, and in some cases it may be public. Hence, it is crucial to identify the right data types for on-chain storage. Further, a mechanism needs to be developed to securely link the on-chain and off-chain data for fast and efficient queries on the blockchain.
Updates on the Research Progress
I’ve worked on a blockchain-based design that allows project members to collectively write the history of a project: a mechanism for a set of independent project participants to write a single source of truth, agreeing on who did what at what point in time. This expanded the scope of the original proposal in that the introduced design can handle not only BIM, but other types of data used in AEC projects. It’s a mechanism for independent parties to curate content (‘reality’) collectively and in a decentralized manner, without reliance on a third-party overseeing the process.
For this purpose, I’ve focused on the question of information sharing in AEC. How can we create a trust-less system which allows us to coordinate data access rights without reliance on a trusted centralized party? The introduced blockchain-based design consists of a protocol that allows a peer-to-peer (P2P) network of project participants to manage the level of access to the project data and also collectively decide on the provenance and rights to information.
System Components
The introduced system consists of few components:
1) Content-addressable and decentralized storage of data
2) Public blockchain-based and immutable documentation of data access rights and flow of data
3) Smart property
The solution uses the concept of Smart Property to manage the data access rights and document the flow of data within the project and over its life cycle. The smart property protocol attaches certain metadata to the native cryptocurrencies of a blockchain (e.g., bitcoin); the ‘colored’ instances of that cryptocurrency, while having certain monetary value, would represent a certain level of access to the people within an organization. For example, a bitcoin carrying one type of metadata could allow its holder to modify a BIM file.
Each project member will have access to a digital and color-aware wallet that stores the ‘colored’ instances of cryptocurrencies she owns at a certain time; the protocol will automatically recognize her right to view, modify, or publish the data based on her balance of colored coins.
The blockchain and the distributed ledger will be used to transparently document the flow of data within the organization; however, the data itself will not be stored directly on the chain; a mathematical summary of the data (e.g., a hash of the data) will be instead used to refer to the data.
The implementation
In this research, I plan to use the interplanetary file system (IPFS) to create a content-addressable and decentralized means of storing project data; in this system, project participants will be referring to files based on ‘what’ they contain, and not ‘where’ they sit on a server. For example, everyone will be referencing a certain version of a BIM file using a 24-digit number (i.e., a hash of the file), regardless of where the file sits. This 24-digit numbers, generated by the IPFS protocol, will also be published to the blockchain.
The Bitcoin blockchain and its ledger will be used to document the flow of information over the life cycle of the project; the public nature of the BTC blockchain provides significantly higher degree of security for the introduced system; the data sitting on its ledger is secured by BTC hash rate and its global economy.
The smart property will be implemented using the BTC colored coin protocol.
I’ve already prototyped the IPFS data storage system, but the smart property protocol is still under development.
Publications (in preparation)
Using Bitcoin Blockchain and Cryptography to Build the AEC/FM’s Distributed and Decentralized Truth Machine: 1. Concept
Using Bitcoin Blockchain and Cryptography to Build the AEC/FM’s Distributed and Decentralized Truth Machine: 2. Implementation
Funding Year:
2019