def _ensure_static_filters(self):

        if self.static_filters_configured:
            return

        self._define_filter(self._filter_container('nova-base',
                                                   ['no-mac-spoofing',
                                                    'no-ip-spoofing',
                                                    'no-arp-spoofing',
                                                    'allow-dhcp-server']))
        self._define_filter(self._filter_container('nova-vpn',
                                                   ['allow-dhcp-server']))
        self._define_filter(self.nova_base_ipv4_filter)
        self._define_filter(self.nova_base_ipv6_filter)
        self._define_filter(self.nova_dhcp_filter)
        self._define_filter(self.nova_ra_filter)
        if FLAGS.allow_same_net_traffic:
            self._define_filter(self.nova_project_filter)
            if FLAGS.use_ipv6:
                self._define_filter(self.nova_project_filter_v6)

        self.static_filters_configured = True
Static filters are filters that have no need to be IP aware.
dataset/ETHPy150Open nii-cloud/dodai-compute/nova/virt/libvirt/firewall.py/NWFilterFirewall._ensure_static_filters