diff --git a/srsepc/hdr/hss/hss.h b/srsepc/hdr/hss/hss.h
index 9c8145974..b9251cc9d 100644
--- a/srsepc/hdr/hss/hss.h
+++ b/srsepc/hdr/hss/hss.h
@@ -55,6 +55,7 @@ public:
   static void cleanup(void);
   int init(hss_args_t *hss_args, srslte::logger* logger);
  
+  uint64_t get_sqn();
   bool get_k_amf_op(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *op);
   
 private:
diff --git a/srsepc/src/hss/hss.cc b/srsepc/src/hss/hss.cc
index e64a3accb..7045d848d 100644
--- a/srsepc/src/hss/hss.cc
+++ b/srsepc/src/hss/hss.cc
@@ -98,11 +98,13 @@ hss::get_k_amf_op(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *op )
   memcpy(amf,amf_tmp,2);
   memcpy(op,op_tmp,16);
 
-  //uint8_t     k[16];
-  //uint8_t     amf[2];  // 3GPP 33.102 v10.0.0 Annex H
-  //uint8_t     op[16];
-
   return true;
 }
 
+uint64_t
+hss::get_sqn( )
+{
+  return 0;
+}
+
 } //namespace srsepc