@Override
  public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable throwable) {
    LOG.trace("Handshake error:", throwable);
    connectionFuture.completeExceptionally(throwable);
    ctx.close();
  }
Generates the next message in the handshake sequence.

@param msg Incoming Message
@return Optional of the next Handshake message that needs to be returned to the peer
ethereum/p2p/src/main/java/org/hyperledger/besu/ethereum/p2p/rlpx/connections/netty/AbstractHandshakeHandler.java