public function createCidrRule($protocol, $cidr_ips, $from_port, $to_port = null) {
    $params = array_merge($this->getCommonRuleParams($protocol, $from_port, $to_port),
      array(
        'security_group_rule[source_type]' => 'cidr_ips',
        'security_group_rule[cidr_ips]' => $cidr_ips
      )
    );

    $this->executeCommand('security_group_rules_create', $params);
  }