Problem Description

Usage of threshold crypto now

Threshold crypto is attracting a lot of attention currently from a practical perspective:

Axelar Network is a blockchain bridge project that uses threshold network as a gatekeeper of tokens between different platforms
Anoma Network is a blockhain that uses threshold network to prevent front running attacks
ConsensusLab is looking to use DKGs to pinpoints state of Filecoin on other blockchains (BTC)
ConsensusLab is looking to use DKGs to checkpoint subnet's state into parents subnets
CryptoNetLab is looking at generalized threshold network to allow smart contract to "have a secret" that can unlock many use cases (data management is one)

Problems with current constructions

Scalability

For all these use cases, ideally we need large set of participants: the larger the size is the more trust we can have in the system. However, doing a DKG (the setup phase) over a large set of participants is unpractical (because of $O(n^2)$ complexity)

Weight compatible

In a permission-less environment participants are associated with weights, and the idea is to randomly sample participants such that the totality of the selected nodes have a weight superior to a given threshold

Doing weighted DKG is extremely impracticable as we usually "emulate" as many nodes as one's weight, which comes back to the scalability issue.

Note: Ferveo from Anoma is maybe the first DKG that tackles this nicely. It is still open questions for us whether it is practicable and the trade offs they are making.

Compatible with existing schemes

Ideally we want DKGs to be compatible with schemes that are already existing on other blockchains so interopability is given. The natural use case for DKGs is threshold signature: if the signature is compatible with well known schemes then the network can act as a participant easily in these other blockchains