@Override
  public String messageName(final int protocolVersion, final int code) {
    switch (code) {
      case IbftV2.PROPOSAL:
        return "Proposal";
      case IbftV2.PREPARE:
        return "Prepare";
      case IbftV2.COMMIT:
        return "Commit";
      case IbftV2.ROUND_CHANGE:
        return "RoundChange";
      default:
        return INVALID_MESSAGE_NAME;
    }
  }
Get ibft sub protocol.

@return the ibft sub protocol
consensus/ibft/src/main/java/org/hyperledger/besu/consensus/ibft/protocol/IbftSubProtocol.java