Fast DDS中提供了两种级别的仿问控制：

1 Domain Governance: 定义域级别的安全策略（全局规则）.

2 DomainParticipant Permissions ： 定义参与者的具体权限（个体规则）

先说一下Domain Governance，配置文件如下所示：

<dds xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:noNamespaceSchemaLocation="omg_shared_ca_domain_governance.xsd">
    <domain_access_rules>
        <domain_rule>
            <domains>
                <id_range>
                    <min>0</min>
                    <max>230</max>
                </id_range>
            </domains>
            <allow_unauthenticated_participants>false</allow_unauthenticated_participants>
            <enable_join_access_control>true</enable_join_access_control>
            <discovery_protection_kind>ENCRYPT</discovery_protection_kind>
            <liveliness_protection_kind>ENCRYPT</liveliness_protection_kind>
            <rtps_protection_kind>ENCRYPT</rtps_protection_kind>
            <topic_access_rules>
                <topic_rule>
                    <topic_expression>HelloWorldTopic</topic_expression>
                    <enable_discovery_protection>true</enable_discovery_protection>
                    <enable_liveliness_protection>false</enable_liveliness_protection>
                    <enable_read_access_control>true</enable_read_access_control>
                    <enable_write_access_control>true</enable_write_access_control>
                    <metadata_protection_kind>ENCRYPT</metadata_protection_kind>
                    <data_protection_kind>ENCRYPT</data_protection_kind>
                </topic_rule>
            </topic_access_rules>
        </domain_rule>
    </domain_access_rules>
</dds>

里面定义了域级别的配置，下面是详细解释：

再说一下 DomainParticipant Permissions，里面定义了某个Participant所在的domain ID范围，以及Publish和Suscribe的Topic。如体如下所示

<dds xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:noNamespaceSchemaLocation="http://www.omg.org/spec/DDS-Security/20170801/omg_shared_ca_permissions.xsd">
    <permissions>
        <grant name="ParticipantPermissions">
            <subject_name>emailAddress=example@eprosima.com, CN=DomainParticipantName, O=eProsima, ST=MA, C=ES</subject_name>
            <validity>
                <not_before>2013-06-01T13:00:00</not_before>
                <not_after>2038-06-01T13:00:00</not_after>
            </validity>
            <allow_rule>
                <domains>
                    <id_range>
                        <min>0</min>
                        <max>230</max>
                    </id_range>
                </domains>
                <publish>
                    <topics>
                        <topic>HelloWorldTopic</topic>
                    </topics>
                </publish>
            </allow_rule>
            <default>DENY</default>
        </grant>

        <!-- Fill the subject name with the information specified in the Participant certificate -->
        <grant name="OtherParticipantPermissions">
            <subject_name> emailAddress=xxx@eprosima.com, CN=xxx, OU=x, O=x, ST=XX, C=XX</subject_name>
            <validity>
                <not_before>2013-06-01T13:00:00</not_before>
                <not_after>2038-06-01T13:00:00</not_after>
            </validity>
            <allow_rule>
                <domains>
                    <id_range>
                        <min>0</min>
                        <max>230</max>
                    </id_range>
                </domains>
                <subscribe>
                    <topics>
                        <topic>HelloWorldTopic</topic>
                    </topics>
                </subscribe>
            </allow_rule>
            <default>DENY</default>
        </grant>
    </permissions>
</dds>