EtherTwin

This repository is part of a research project on blockchain-based Digital Twins: https://doi.org/10.1016/j.ipm.2020.102425

The EtherTwin prototype originates from a research approach to share Digital Twin data over its lifecycle. To allow the participation of the multiple lifecycle parties without relying on trusted third parties (TTPs), EtherTwin relies on a distributed approach by integrating the Ethereum blockchain and the distributed hash table (DHT) Swarm. On the basis of AutomationML (AML) files that specify assets, a Digital Twin can be created and shared with the twin's lifecycle parties. The EtherTwin prototype allows to:

• create Digital Twins
• share each twin
• upload documents
• update twin specification and documents (versioning)
• create sensor data feeds
• control access of users by lifecycle roles and asset attributes
• list asset components (specification parsing)

An exemplary use case is given in the following video. The video is based on a slightly outdated version of EtherTwin, but it illustrates the core functionality well.

Live demo: For a live demonstration of the prototype using a private Ethereum blockchain, visit http://ethertwin.ur.de/. An Ethereum account will be automatically created for you with the private key stored in your browser's local storage. Before you can issue transactions, you'll need to request some Ether on our test blockchain at http://ethertwin.ur.de:3333/0x0 (replace 0x0 with your Ethereum account).

Project setup

npm install

Prerequisites

Download Parity to set up your Ethereum blockchain. Create a folder network, add the parity.exe and password.txt. Then run the following console command in the network folder to start your blockchain:

parity --config dev --unlock "0x00a329c0648769a73afac7f9381e08fb43dbea72" --password .\password.txt --unsafe-expose --jsonrpc-cors=all

Download Swarm to set up the DHT. Then run the following console command:

swarm --bzzaccount <accountAddress> --config ./config.toml --datadir . --httpaddr=0.0.0.0 --corsdomain '*' --password password.txt```

Install Truffle to initialize the Smart Contracts:

npm -i truffle
truffle migrate --network parity

Configuration

Add config.json with the corresponding values (IP) for the Swarm DHT etc. Note that the values for the registry and authorization are optional:

{
  "swarm": "http://<IP>:5000",
  "ethereum": {
    "rpc": "ws://<IP>:8546",
    "registry": "<RegistryContractAddress>",
    "authorization": "<AuthorizationContractAddress>"
  }
  "agent_key": "<ethereum private key for device agent>"
}

You also need to add an appropriate log file in the misc folder, for example by renaming logs.xml.example to logs.xml.

Run

Run the device agent

npm run agent

Run the main web app for development with hot reloads

npm run serve

Build static files for deployment

npm run build

Usage

An exemplary specification for the twin creation can be found at misc/CandyFactory.aml, which originates from the CPS Twinning prototype. Various screenshots showing the EtherTwin prototype functionality can be found at misc/Screenshots. The following screenshot illustrates the Home site of our EtherTwin prototype - showing all twins of the user.

Research and Citation

Please consider citing our publication if you are using our EtherTwin prototype for your research: https://doi.org/10.1016/j.ipm.2020.102425

B. Putz, M. Dietz, P. Empl, and G. Pernul, "EtherTwin: Blockchain-based Secure Digital Twin Information Management", Information Processing & Management, vol. 58, no. 1, 2021.