def get_config_options(otype):
    """ Return list of valid configuration options for nodes and dispatcher."""
    if otype is 'node':
        return ['node_name', 'node_type', 'node_id', 'node_description', 'primary_node', 'ip', 'port_frontend', 'port_backend', 'port_publisher', 'n_responders', 'lsl_stream_name', 'primary_n_channels', 'primary_channel_names', 'primary_channel_descriptions', 'primary_sampling_rate', 'primary_buffer_size_s', 'run_publisher', 'secondary_node', 'secondary_n_channels', 'secondary_buffer_size', 'secondary_channel_names', 'secondary_channel_descriptions', 'default_channel']
    elif otype is 'dispatcher':
        return ['node_list', 'port', 'ip', 'n_threads', 'run_pubsub_proxy', 'proxy_port_in', 'proxy_port_out']
    else:
        return None