diff --git a/srsue/hdr/ue_base.h b/srsue/hdr/ue_base.h
index 411896f70..634219083 100644
--- a/srsue/hdr/ue_base.h
+++ b/srsue/hdr/ue_base.h
@@ -109,6 +109,7 @@ typedef struct {
   std::string ue_cateogry;
   bool metrics_csv_enable;
   std::string metrics_csv_filename;
+  std::string ip_netmask;
 }expert_args_t;
 
 typedef struct {