diff --git a/lib/test/common/test_f12345.cc b/lib/test/common/test_f12345.cc
index 1c5375c43..e75d80bd7 100644
--- a/lib/test/common/test_f12345.cc
+++ b/lib/test/common/test_f12345.cc
@@ -63,9 +63,19 @@ void test_set_2()
   uint8_t op[] = {0xcd, 0xc2, 0x02, 0xd5, 0x12, 0x3e, 0x20, 0xf6, 0x2b, 0x6d, 0x67, 0x6a, 0xc7, 0x2c, 0xb3, 0x18};
   // f1
 
-   uint8_t mac_o[8]; 
+  uint8_t opc_o[16];
+  err_lte = liblte_compute_opc(k,op,opc_o);
+  assert(err_lte == LIBLTE_SUCCESS);
+
+  arrprint(opc_o, sizeof(opc_o));
+
+  uint8_t opc_a[] = {0xcd, 0x63, 0xcb, 0x71, 0x95, 0x4a, 0x9f, 0x4e, 0x48, 0xa5, 0x99, 0x4e, 0x37, 0xa0, 0x2b, 0xaf};
+  err_cmp = arrcmp(opc_o,opc_a,sizeof(opc_o));
+  assert(err_cmp == 0);
+
+  uint8_t mac_o[8];
   err_lte = liblte_security_milenage_f1(k,
-                                        op,
+                                        opc_o,
                                         rand,
                                         sqn,
                                         amf,
@@ -84,7 +94,7 @@ void test_set_2()
 
   uint8_t mac_so[8];
   err_lte = liblte_security_milenage_f1_star(k,
-                                   op,
+                                   opc_o,
                                    rand,
                                    sqn,
                                    amf,
@@ -93,9 +103,9 @@ void test_set_2()
   assert(err_lte == LIBLTE_SUCCESS);
 
   uint8_t mac_s[] = {0x01, 0xcf, 0xaf, 0x9e, 0xc4, 0xe8, 0x71, 0xe9};
-  
+
   arrprint(mac_so, sizeof(mac_so));
-  
+
   err_cmp = arrcmp(mac_so, mac_s, sizeof(mac_s));
   assert(err_cmp == 0);
 
@@ -106,7 +116,7 @@ void test_set_2()
   uint8_t ak_o[6];
 
   err_lte = liblte_security_milenage_f2345(k,
-                                 op,
+                                 opc_o,
                                  rand,
                                  res_o,
                                  ck_o,
@@ -126,7 +136,7 @@ void test_set_2()
   err_cmp = arrcmp(res_o, res, sizeof(res));
   assert(err_cmp == 0);
 
-  // CK 
+  // CK
   arrprint(ck_o, sizeof(ck_o));
 
   err_cmp = arrcmp(ck_o, ck, sizeof(ck));
@@ -142,10 +152,10 @@ void test_set_2()
   err_cmp = arrcmp(ak_o, ak, sizeof(ak));
   assert(err_cmp == 0);
 
-  // f star 
+  // f star
   uint8_t ak_star_o[6];
-  
-  err_lte = liblte_security_milenage_f5_star(k, op, rand, ak_star_o);
+
+  err_lte = liblte_security_milenage_f5_star(k, opc_o, rand, ak_star_o);
   assert(err_lte == LIBLTE_SUCCESS);
 
   arrprint(ak_star_o, sizeof(ak_star_o));
@@ -160,8 +170,9 @@ void test_set_2()
 */
 
 int main(int argc, char * argv[]) {
-  /*
+
   test_set_2();
+  /*
   test_set_3();
   test_set_4();
   test_set_5();
diff --git a/srsepc/hdr/hss/hss.h b/srsepc/hdr/hss/hss.h
index 26bbe8aa6..c81ec6296 100644
--- a/srsepc/hdr/hss/hss.h
+++ b/srsepc/hdr/hss/hss.h
@@ -91,7 +91,7 @@ private:
 
 
   void gen_rand(uint8_t rand_[16]);
-  bool get_k_amf_op_sqn(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *op, uint8_t *sqn);
+  bool get_k_amf_opc_sqn(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *op, uint8_t *sqn);
 
   bool gen_auth_info_answer_milenage(uint64_t imsi, uint8_t *k_asme, uint8_t *autn, uint8_t *rand, uint8_t *xres);
   bool gen_auth_info_answer_xor(uint64_t imsi, uint8_t *k_asme, uint8_t *autn, uint8_t *rand, uint8_t *xres);
diff --git a/srsepc/src/hss/hss.cc b/srsepc/src/hss/hss.cc
index eaf206f5c..fa4c89bd9 100644
--- a/srsepc/src/hss/hss.cc
+++ b/srsepc/src/hss/hss.cc
@@ -180,7 +180,6 @@ hss::read_db_file(std::string db_filename)
         m_hss_log->error("Neither OP nor OPc configured.\n");
         return false;
       }
-      get_uint_vec_from_hex_str(split[4],ue_ctx->op,16);
       get_uint_vec_from_hex_str(split[5],ue_ctx->amf,2);
       get_uint_vec_from_hex_str(split[6],ue_ctx->sqn,6);
 
@@ -321,10 +320,10 @@ hss::resync_sqn_milenage(uint64_t imsi, uint8_t *auts)
 
   uint8_t k[16];
   uint8_t amf[2];
-  uint8_t op[16];
+  uint8_t opc[16];
   uint8_t sqn[6];
 
-  if(!get_k_amf_op_sqn(imsi, k, amf, op, sqn))
+  if(!get_k_amf_opc_sqn(imsi, k, amf, opc, sqn))
   {
     return false;
   }
@@ -340,13 +339,13 @@ hss::resync_sqn_milenage(uint64_t imsi, uint8_t *auts)
   }
 
   m_hss_log->debug_hex(k, 16, "User Key : ");
-  m_hss_log->debug_hex(op, 16, "User OP : ");
+  m_hss_log->debug_hex(opc, 16, "User OPc : ");
   m_hss_log->debug_hex(last_rand, 16, "User Last Rand : ");
   m_hss_log->debug_hex(auts, 16, "AUTS : ");
   m_hss_log->debug_hex(sqn_ms_xor_ak, 6, "SQN xor AK : ");
   m_hss_log->debug_hex(mac_s, 8, "MAC : ");
 
-  security_milenage_f5_star(k, op, last_rand, ak);
+  security_milenage_f5_star(k, opc, last_rand, ak);
   m_hss_log->debug_hex(ak, 6, "Resynch AK : ");
 
   uint8_t sqn_ms[6];
@@ -359,17 +358,10 @@ hss::resync_sqn_milenage(uint64_t imsi, uint8_t *auts)
 
   uint8_t mac_s_tmp[8];
 
-  security_milenage_f1_star(k, op, last_rand, sqn_ms, amf, mac_s_tmp);
+  security_milenage_f1_star(k, opc, last_rand, sqn_ms, amf, mac_s_tmp);
 
   m_hss_log->debug_hex(mac_s_tmp, 8, "MAC calc : ");
-  /*
-  for(int i=0; i<8; i++){
-    if(!(mac_s_tmp[i] == mac_s[i])){
-      m_hss_log->error("Calculated MAC does not match sent MAC\n");
-      return false;
-    }
-  }
-  */
+
   set_sqn(imsi, sqn_ms);
 
   return true;
@@ -380,7 +372,7 @@ hss::gen_auth_info_answer_milenage(uint64_t imsi, uint8_t *k_asme, uint8_t *autn
 {
   uint8_t k[16];
   uint8_t amf[2];
-  uint8_t op[16];
+  uint8_t opc[16];
   uint8_t sqn[6];
 
   uint8_t     ck[16];
@@ -389,14 +381,14 @@ hss::gen_auth_info_answer_milenage(uint64_t imsi, uint8_t *k_asme, uint8_t *autn
   uint8_t     mac[8];
 
 
-  if(!get_k_amf_op_sqn(imsi, k, amf, op, sqn))
+  if(!get_k_amf_opc_sqn(imsi, k, amf, opc, sqn))
   {
     return false;
   }
   gen_rand(rand);
 
   security_milenage_f2345( k,
-                           op,
+                           opc,
                            rand,
                            xres,
                            ck,
@@ -404,7 +396,7 @@ hss::gen_auth_info_answer_milenage(uint64_t imsi, uint8_t *k_asme, uint8_t *autn
                            ak);
 
   m_hss_log->debug_hex(k, 16, "User Key : ");
-  m_hss_log->debug_hex(op, 16, "User OP : ");
+  m_hss_log->debug_hex(opc, 16, "User OPc : ");
   m_hss_log->debug_hex(rand, 16, "User Rand : ");
   m_hss_log->debug_hex(xres, 8, "User XRES: ");
   m_hss_log->debug_hex(ck, 16, "User CK: ");
@@ -412,7 +404,7 @@ hss::gen_auth_info_answer_milenage(uint64_t imsi, uint8_t *k_asme, uint8_t *autn
   m_hss_log->debug_hex(ak, 6, "User AK: ");
 
   security_milenage_f1( k,
-                        op,
+                        opc,
                         rand,
                         sqn,
                         amf,
@@ -459,7 +451,7 @@ hss::gen_auth_info_answer_xor(uint64_t imsi, uint8_t *k_asme, uint8_t *autn, uin
 {
   uint8_t k[16];
   uint8_t amf[2];
-  uint8_t op[16];
+  uint8_t opc[16];
   uint8_t sqn[6];
 
   uint8_t  xdout[16];
@@ -472,7 +464,7 @@ hss::gen_auth_info_answer_xor(uint64_t imsi, uint8_t *k_asme, uint8_t *autn, uin
 
   int i = 0;
 
-  if(!get_k_amf_op_sqn(imsi, k, amf, op, sqn))
+  if(!get_k_amf_opc_sqn(imsi, k, amf, opc, sqn))
   {
     return false;
   }
@@ -493,7 +485,7 @@ hss::gen_auth_info_answer_xor(uint64_t imsi, uint8_t *k_asme, uint8_t *autn, uin
   }
 
   m_hss_log->debug_hex(k, 16, "User Key : ");
-  m_hss_log->debug_hex(op, 16, "User OP : ");
+  m_hss_log->debug_hex(opc, 16, "User OPc : ");
   m_hss_log->debug_hex(rand, 16, "User Rand : ");
   m_hss_log->debug_hex(xres, 8, "User XRES: ");
   m_hss_log->debug_hex(ck, 16, "User CK: ");
@@ -565,7 +557,7 @@ hss::gen_auth_info_answer_xor(uint64_t imsi, uint8_t *k_asme, uint8_t *autn, uin
 
 
 bool
-hss::get_k_amf_op_sqn(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *op, uint8_t *sqn)
+hss::get_k_amf_opc_sqn(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *opc, uint8_t *sqn)
 {
 
   std::map<uint64_t,hss_ue_ctx_t*>::iterator ue_ctx_it = m_imsi_to_ue_ctx.find(imsi);
@@ -579,7 +571,7 @@ hss::get_k_amf_op_sqn(uint64_t imsi, uint8_t *k, uint8_t *amf, uint8_t *op, uint
   m_hss_log->info("Found User %015lu\n",imsi);
   memcpy(k, ue_ctx->key, 16);
   memcpy(amf, ue_ctx->amf, 2);
-  memcpy(op, ue_ctx->op, 16);
+  memcpy(opc, ue_ctx->opc, 16);
   memcpy(sqn, ue_ctx->sqn, 6);
 
   return true;
diff --git a/srsue/src/main.cc b/srsue/src/main.cc
index eb9bd673b..ccf7ae88d 100644
--- a/srsue/src/main.cc
+++ b/srsue/src/main.cc
@@ -381,7 +381,6 @@ void parse_args(all_args_t *args, int argc, char *argv[]) {
     }
   }
 
-  cout << vm.count("usim.op") <<endl;
   // Apply all_level to any unset layers
   if (vm.count("log.all_level")) {
     if (!vm.count("log.phy_level")) {