Proof of Staked Authority (PoSA) is a hybrid consensus mechanism that combines elements of Proof of Stake (PoS) and Proof of Authority (PoA). In this model, validators must not only stake their tokens, as in PoS, but also pass an identity verification, similar to PoA, to confirm their credibility and reliability.

Key Features of PoSA:

Token Staking:
- Participants must stake (freeze) their tokens to become validators. Like PoS, the more tokens staked, the higher the chance of being selected to validate blocks.
Trust through Identification:
- As in PoA, validators in PoSA must be known and verified individuals or organizations, which increases trust in the network. This helps protect the system from malicious actors and prevents anonymous validators from participating.
High Performance:
- PoSA ensures fast transaction validation and low latency, making it an effective mechanism for high-throughput blockchains.
Security:
- The combination of staking and identity verification reduces risks from attacks, such as Sybil attacks (where an attacker can create many fake validators to gain control).

Example of Use:

Binance Smart Chain (BSC) uses the PoSA mechanism, where validators are verified and stake their BNB tokens to participate in validating transactions and creating blocks.

Conclusion:

PoSA is an efficient hybrid mechanism that combines the economic incentives of PoS with the reliability of PoA, offering high performance and security for networks where both speed and trust in validators are crucial.