Module keygen 

CMP20 non-interactive distributed key generation over P-256.

CMP20’s headline DKG improvement over GG18 is that key generation is non-interactive: a single broadcast round suffices. Each party deals a Feldman VSS and bundles, into one outgoing message, both its commitment list (broadcast) and every peer’s polynomial evaluation (directed). Recipients verify everything locally in the same round and assemble their combined share + the joint public key without any further interaction.

After the round every party holds a combined share x_i = sum_d f_d(i) and the joint public key X = prod_d g^{secret_d} = g^{sum secret_d}. The combined secret is never reconstructed.

Rounds

• Round 1 — deal and assemble. Broadcast Feldman commitments plus a directed share for every peer, all tagged for round 1. On receipt, verify each dealer’s commitments against the bundled evaluation addressed to us, sum the verified shares into x_i, and compute the joint public key. Complete.

Structs

Cmp20DkgP256

CMP20 DKG scheme over P-256. Registered as CMP20-ECDSA-P256.

Cmp20DkgSession

Functions

parse_share

Parse a DKG-produced share blob.