Нашел упоминание:
https://github.com/renproject/ren/wiki/GatewaysThe Darknodes responsible for the shard at epoch E will generate a new ECDSA private key using the RZL sMPC algorithm (no Darknodes ever see the private key). This is done is such a way that the new ECDSA public key is known, but the respective Shamir’s secret shares are encrypted for the Darknodes at epoch E+1. The Darknodes at E combine all UTXOs into a single transaction that forwards all BTC to the newly generated ECDSA public key.
The ECDSA public key and encrypted Shamir’s secret shares are stored as state in the base block (see Consensus). The Darknodes at epoch E+1 get the public key and their respective share of the private key from the base block, and the rotation is finished. For the duration of epoch E+1, the Darknodes at epoch E will continue to support gateway scripts built at epoch E, and will transform all relevant RenVM transactions for E+1.
Но понятнее не стало.
Старые ноды из прошлой эпохи генерируют новый приватник совместо, сохраняют его в каком-то базовом блоке и затем новая партия нод получает оттуда свои части.
Так получается старые ноды совместно знают и новый ключ, разве нет?