Threshold Demo

Imagine you have many parties with large quantities of data, where some data collection or analysis is done by a smaller number of more powerful entities. We consider this situation here in a simple example where "lower" parties submit data values to the computation, and "upper" parties count how many of those inputs are larger than some threshold value, and return that count.

Running Demo

1. Running a server:

   node demos/threshold/server.js

2. Either open browser based parties by going to http://localhost:8080/demos/threshold/client.html in the browser, or a node.js party by running

   node demos/threshold/party.js <input> <lower party count> <upper party count>

   If the lower party count is n, then the first n parties to submit will be considered lower parties. Any subsequent parties' are thus upper parties and their inputs will be ignored.

3. Running tests: run the following. Note that you do not need to have the server running when running the tests; they run the server on their own.

   npm run-script test-demo -- demos/threshold/test.js

File structure

The demo consists of the following parts:

1. Server script: server.js
2. Web Based Party: Made from the following files:
   • client.html: UI for the browser.
   • client.js: Handlers for UI buttons and input validations.
3. Node.js-Based Party:
   • party.js: Main entry point. Parses input from the command line and initializes the computation.
4. The MPC protocol: Implemented in mpc.js. This file is used in both the browser and node.js versions of the demo.
5. test.js: mocha unit tests.
6. Documentation:
   • This README.md file.