Thanks, this paper did help improve my understanding of what might be going on, but @victorshoup mentions in this video as well as this post that none of the ECDSA threshold sharing protocols described in that paper satisfied their needs so they designed a new protocol. I couldn’t find a description of the ECDSA threshold protocol that was decided upon.
@Manu mentioned:
The full cryptographic details of the interactive DKG and threshold ECDSA signing will be published in a paper that should appear in the following weeks.
I just found the paper, it came out a couple of weeks ago, here.
This is what I needed to understand what’s going on, and I was able to reproduce resharing to a larger number of nodes. The key insights I was missing were:
- Lambda values can simply be created with the
Randomprotocol - The previous set of dealers can reshare to a larger number of recipients using the same protocol