Algorand

Algorand is a company implementing an open source public ledger utilizing the Byzantine Agreement message-passing protocol to reach consensus among network participants. The Algorand protocol is still in the development phase and is designed to be a blockchain basedblockchain-based payments platform.

Users run a verifiable random function based on a seed generated in the previous block to select a leader, who is in charge of proposing the next block, and members of a committee who are responsible for voting on the validity of that block. This cryptographic lottery results in a rotating, random selection of committee members who are self selecting. Committee members run the computation to see if they won the lottery trivially, and in secret so they do not reveal their identities until they pass their message, or vote to the network with a credential in the form of a digital proof or signature. This secrecy is intended to improve network resilience against committee member corruption from a malicious adversary by obfuscating the identity of the committee until after they have propagated their information to the network.

The Byzantine Agreement process takes multiple steps, introducing a vulnerability where adversaries may corrupt committee members after they have revealed themselves in the first step. Algorand seeks to solvessolve this issue by having each step in the Byzantine Agreement process performed by a player-replacable protocol in which the committee members are swapped out at each step in the protocol — making the adversary unable to predict the committee member in any step until after they have performed their task.

Yongge Wang with his recetnrecent paper "Another look at ALGORAND" (May 11, 2019) says it is possible to fork Algorand even with 1/3 malicious users and possibility to bribe validators easily is not unrealistic.