SG Consensus Algorithm Implementation¶

SG Consensus algorithm is based on GOSSIP protocol.
System uses libp2p library for P2P Gossip messaging.

Gossip Message Types

BLOCK ANNOUNCE
VERIFICATION
TRANSACTIONS
STATUS
BLOCK REQUEST

Consensus protocol uses VERIFICATION gossip message for consensus process. There are two different types of VERIFICATION message

VOTE message
FIN message

There are three different types of Vote Messages\ \ Primary Propose\ Primary node broadcasts Primary Propose message to all nodes to validate a transaction.\ Pre Vote\ Nodes after receiving Primary Propose send Pre-Vote message (initial vote) to all other nodes.\ Pre Commit\ Nodes after receiving pre-votes from other nodes sends stronger commitment using pre-commit vote.

Vote Message Format\ | Voting Round Number | Membership Counter | Message Data |

Consensus Protocol Message Sequences¶

sequenceDiagram
    PN->>N1: Primary Propose 
    PN->>N2: Primary Propose 
    N1->>N2: Pre-Vote
    PN->>N1: Pre-Vote
    PN->>N2: Pre-Vote
    N2->>N1: Pre-vote
    N2->>PN: Pre-Vote 
    N1->>PN: Pre-Vote 
    N2->>PN: Pre-Commit 
    PN->>N1: Pre-Commit
    N2->>N1: Pre-Commit
    N1->>PN: Pre-Commit
    N1->>N2: Pre-Commit
    PN->>N2: Pre-Commit 
    N1->>N2: Fin 
    PN->>N2: Fin
    PN->>N1: Fin
    N2->>PN: Fin
    N1->>PN: Fin 
    N2->>N1: Fin