MultiversX's consensus mechanism, Secure Proof of Stake (SPoS), is engineered to make each round of consensus fast, secure, and fair. SPoS keeps things moving by picking validators using an unpredictable randomness source. Here’s the twist: this randomness isn’t guessed or predetermined; it’s generated from the previous block and signed by the current block proposer, meaning it’s impossible to predict, even for a split second. This ensures validator selection is as secure as it is surprising!

Each round, a new block proposer and validation group are picked at lightning speed, thanks to SPoS’s deterministic selection process. No lengthy debates here; once the randomness source is signed, the proposer with the smallest hash takes the lead, and everything wraps up in around 100 milliseconds.

Speed and security come from these ultra-short rounds, making it hard for any attacker to swoop in and influence the process. SPoS also incentivizes reliability by rewarding validators with high ratings—so those who keep their nodes up and running have a better shot at selection.

Once a block is proposed, validators sign off using a modified BLS multisignature scheme in just two rounds of communication. The result? A secure, resilient network that combines speed, fairness, and stability, ensuring that MultiversX runs as efficiently as possible without sacrificing security.

Reference: https://docs.multiversx.com/learn/consensus/