diff --git a/schema/projects/aif.xsd b/schema/projects/aif.xsd
index 0fc76bf..6d9797d 100644
--- a/schema/projects/aif.xsd
+++ b/schema/projects/aif.xsd
@@ -219,8 +219,8 @@
                                             <xs:complexType>
                                                 <xs:attribute name="name" type="t_std_nonempty" use="required"/>
                                                 <xs:attribute name="enabled" type="xs:boolean" use="optional" default="true"/>
-                                                <xs:attribute name="sigLevel" type="t_std_nonempty" use="required"/>
-                                                <xs:attribute name="mirror" type="t_aif_pacuri" use="required"/>
+                                                <xs:attribute name="sigLevel" type="t_std_nonempty" use="optional"/>
+                                                <xs:attribute name="mirror" type="t_aif_pacuri" use="optional"/>
                                             </xs:complexType>
                                         </xs:element>
                                     </xs:sequence>