diff --git a/msc_tests/BSC_ConnectionHandler.ttcn b/msc_tests/BSC_ConnectionHandler.ttcn
index 39acfb7..ee0e0ae 100644
--- a/msc_tests/BSC_ConnectionHandler.ttcn
+++ b/msc_tests/BSC_ConnectionHandler.ttcn
@@ -149,9 +149,15 @@
 	}
 
 	if (expect_auth) {
+		var OCT16 rand := 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'O;
+		var OCT4 sres := 'bbbbbbbb'O;
+		var GSUP_IE auth_tuple := valueof(ts_GSUP_IE_AuthTuple2G(rand, sres,
+									 'cccccccccccccccc'O));
 		GSUP.receive(tr_GSUP_SAI_REQ(g_pars.imsi));
-		/* FIXME */
-		//GSUP.send(tr_GSUP_SAI_RES());
+		GSUP.send(ts_GSUP_SAI_RES(g_pars.imsi, auth_tuple));
+
+		BSSAP.receive(tr_PDU_DTAP_MT(tr_ML3_MT_MM_AUTH_REQ(rand)));
+		BSSAP.send(ts_PDU_DTAP_MO(ts_ML3_MT_MM_AUTH_RESP_2G(sres)));
 	}
 
 	/* Expect MSC to perform LU with HLR */