@VisibleForTesting
  void broadcastBlockRange(
      final long earliestBlockNumber, final long latestBlockNumber, final Hash blockHash) {
    List<EthPeer> peers = getPeersSupportingBlockRangeUpdate();
    LOG.info(
        "Broadcasting blockRange=[{}, {}, {}] to {} peers",
        earliestBlockNumber,
        latestBlockNumber,
        blockHash,
        peers.size());
    if (peers.isEmpty()) {
      LOG.debug("No peers available that support BLOCK_RANGE_UPDATE message.");
      return;
    }
    final BlockRangeUpdateMessage blockRangeUpdateMessage =
        BlockRangeUpdateMessage.create(earliestBlockNumber, latestBlockNumber, blockHash);
    peers.forEach(peer -> broadcastToPeer(peer, blockRangeUpdateMessage));
  }
Broadcasts the block range update message to all peers that support it.

@param earliestBlockNumber the earliest block number
@param latestBlockNumber the latest block number
@param blockHash the hash of the block
ethereum/eth/src/main/java/org/hyperledger/besu/ethereum/eth/sync/BlockRangeBroadcaster.java