diff --git a/xos/synchronizer/models/hippie-oss.xproto b/xos/synchronizer/models/hippie-oss.xproto
index 558d8b4..671089a 100644
--- a/xos/synchronizer/models/hippie-oss.xproto
+++ b/xos/synchronizer/models/hippie-oss.xproto
@@ -4,13 +4,15 @@
 message HippieOSSService (Service){
     option verbose_name = "HippieOSS Service";
     option kind = "OSS";
+
+    optional string blacklist = 1 [help_text = "A comma separated list of ONUs that are deemed not to be valid ONUs", null = True, db_index = False, blank = False];
 }
 
 message HippieOSSServiceInstance (ServiceInstance){
     option owner_class_name = "HippieOSSService";
     option verbose_name = "HippieOSS Service Instance";
 
-    required bool valid = 1 [help_text = "Wether this ONU has been validated by the external OSS", default = False, null = False, db_index = False, blank = False];
+    required string valid = 1 [default = "awaiting", choices = "(('awaiting', 'Awaiting Validation'), ('valid', 'Valid'), ('invalid', 'Invalid'))", help_text = "Wether this ONU has been validated by the external OSS", null = False, blank = False];
     required string serial_number = 2 [max_length = 254, null = False, db_index = False, blank = False, tosca_key=True, unique = True];
     required int32 uni_port_id = 3 [null = False, db_index = False, blank = False];
     required string of_dpid = 4 [max_length = 254, null = False, db_index = False, blank = False];