Help: possible to scale?

[jaredweinfurtner]

Is it possible to have potentially thousands of clients garble their shares, send it to 2 nodes to perform the mpc calculations? I would like to create a demo showing 10000 homes provide their occupancy in order to know the city's total occupancy without knowing each individual home's occupancy. Would it be possible for each home to garble their secret (occupancy - unsigned integer - and send it to 2 mpc nodes to perform the aggregation function?

[markkurossi]

The basic garbled circuit protocol works with two parties, but there are versions for n>2. I started implementing BMR protocol (enabled with -bmr command line argument) but the implementation is not completed. I also don't know if that protocol would scale to tens of thousands of parties because of the additional communication requirements between parties. Another option could be using custom protocol, similar to the one used in the Boston University's Gender Pay Equity project (http://www.cs.bu.edu/techreports/pdf/2015-009-mpc-compensation.pdf). I think that could scale to your demo.