The block proposer / round leader signs the previous randomness source with their BLS signature to generate the new source, and so on.
See here:
https://medium.com/elrondnetwork/elrond-improvement-change-in-consensus-and-randomness-source-d764a3fad35
The block proposer / round leader signs the previous randomness source with their BLS signature to generate the new source, and so on. See here: https://medium.com/elrondnetwork/elrond-improvement-change-in-consensus-and-randomness-source-d764a3fad35