diff --git a/bsc/BSC_Tests.ttcn b/bsc/BSC_Tests.ttcn
index bcefe67..48766f1 100644
--- a/bsc/BSC_Tests.ttcn
+++ b/bsc/BSC_Tests.ttcn
@@ -228,7 +228,7 @@
 	alt {
 	[] IPA_RSL[i].receive(tr_ASP_IPA_EV(ASP_IPA_EVENT_ID_ACK)) {
 		T.stop;
-		IPA_RSL[i].send(ts_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,ts_RSL_PAGING_LOAD_IND(23)));
+		IPA_RSL[i].send(ts_ASP_RSL_UD(ts_RSL_PAGING_LOAD_IND(23)));
 		}
 	[] IPA_RSL[i].receive(ASP_IPA_Event:?) { repeat }
 	[] IPA_RSL[i].receive { repeat }
@@ -398,7 +398,7 @@
 
 	T.start;
 	alt {
-	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(sid, t_rx)) -> value rx_rsl_ud {
+	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(t_rx, sid)) -> value rx_rsl_ud {
 		T.stop;
 		}
 	[] IPA_RSL[bts_nr].receive { repeat; }
@@ -413,7 +413,7 @@
 /* helper function to transmit RSL on a given BTS/stream */
 function f_ipa_tx(integer bts_nr, template RSL_Message t_tx, IpaStreamId sid := IPAC_PROTO_RSL_TRX0)
 runs on test_CT {
-	IPA_RSL[bts_nr].send(ts_ASP_RSL_UD(sid, t_tx));
+	IPA_RSL[bts_nr].send(ts_ASP_RSL_UD(t_tx, sid));
 }
 
 
@@ -424,7 +424,7 @@
 
 	f_init(1);
 
-	IPA_RSL[0].send(ts_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,ts_RSL_CHAN_RQD('23'O, 23)));
+	IPA_RSL[0].send(ts_ASP_RSL_UD(ts_RSL_CHAN_RQD('23'O, 23)));
 	rsl_unused := f_exp_ipa_rx(0, tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV));
 	setverdict(pass);
 }
@@ -438,7 +438,7 @@
 	f_init(1);
 
 	chreq_total := f_ctrl_get_ratectr_abs(IPA_CTRL, "bts", 0, "chreq:total");
-	IPA_RSL[0].send(ts_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,ts_RSL_CHAN_RQD('23'O, 23)));
+	IPA_RSL[0].send(ts_ASP_RSL_UD(ts_RSL_CHAN_RQD('23'O, 23)));
 	rsl_unused := f_exp_ipa_rx(0, tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV));
 	f_ctrl_get_exp_ratectr_abs(IPA_CTRL, "bts", 0, "chreq:total", chreq_total+1);
 
@@ -554,11 +554,10 @@
 	f_ipa_tx(0, ts_RSL_CHAN_RQD('42'O, 42));
 
 	alt {
-	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,
-				tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV))) {
+	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(tr_RSL_MsgTypeD(RSL_MT_CHAN_ACTIV))) {
 		setverdict(fail, "Received CHAN ACT ACK without resources?!?");
 		}
-	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_IMM_ASSIGN(?))) -> value rsl_ud {
+	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(tr_RSL_IMM_ASSIGN(?))) -> value rsl_ud {
 		var GsmRrMessage rr;
 		/* match on IMM ASS REJ */
 		rr := dec_GsmRrMessage(rsl_ud.rsl.ies[1].body.full_imm_ass_info.payload);
@@ -590,13 +589,11 @@
 
 	/* Expect CHANnel RELease */
 	alt {
-	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,
-			      tr_RSL_MsgTypeD(RSL_MT_RF_CHAN_REL))) {
+	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(tr_RSL_MsgTypeD(RSL_MT_RF_CHAN_REL))) {
 		log("Received CHANnel RELease");
 		setverdict(pass);
 		}
-	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,
-			      tr_RSL_IMM_ASSIGN(?))) {
+	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(tr_RSL_IMM_ASSIGN(?))) {
 		/* See OS#3709, OsmoBSC should not send Immediate
 		 * Assignment Reject since a dedicated channel was
 		 * already allocated, and Immediate Assignment was
@@ -926,21 +923,19 @@
 	log("f_expect_chan_rel() expecting: expect_deact_sacch=", expect_deact_sacch, " expect_rr_chan_rel=", expect_rr_chan_rel,
 	    " expect_rll_rel_req=", expect_rll_rel_req);
 	alt {
-	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,
-					tr_RSL_DEACT_SACCH(rsl_chan_nr))) {
+	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(tr_RSL_DEACT_SACCH(rsl_chan_nr))) {
 		got_deact_sacch := true;
 		repeat;
 	}
-	[is_csfb] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_DATA_REQ(rsl_chan_nr, ?, decmatch tr_RRM_RR_RELEASE_CSFB))) {
+	[is_csfb] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(tr_RSL_DATA_REQ(rsl_chan_nr, ?, decmatch tr_RRM_RR_RELEASE_CSFB))) {
 		got_rr_chan_rel := true;
 		repeat;
 	}
-	[not is_csfb] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_DATA_REQ(rsl_chan_nr, ?, decmatch tr_RRM_RR_RELEASE))) {
+	[not is_csfb] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(tr_RSL_DATA_REQ(rsl_chan_nr, ?, decmatch tr_RRM_RR_RELEASE))) {
 		got_rr_chan_rel := true;
 		repeat;
 	}
-	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,
-					tr_RSL_REL_REQ(rsl_chan_nr, ?))) {
+	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(tr_RSL_REL_REQ(rsl_chan_nr, ?))) {
 		got_rll_rel_req := true;
 		/* FIXME: Why are we getting this for LinkID SACCH? */
 		if (handle_rll_rel) {
@@ -948,13 +943,12 @@
 		}
 		repeat;
 	}
-	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0,
-						tr_RSL_MsgTypeD(RSL_MT_RF_CHAN_REL))) {
+	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(tr_RSL_MsgTypeD(RSL_MT_RF_CHAN_REL))) {
 		/* respond with CHAN REL ACK */
 		f_ipa_tx(0, ts_RSL_RF_CHAN_REL_ACK(rsl_chan_nr));
 		}
 	/* ignore any user data */
-	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_MsgTypeR(?))) {
+	[] IPA_RSL[bts_nr].receive(tr_ASP_RSL_UD(tr_RSL_MsgTypeR(?))) {
 		repeat;
 		}
 	}
@@ -1348,7 +1342,7 @@
 		}
 		T.start;
 		alt {
-		[] IPA_RSL[i].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_PAGING_CMD(mi))) {
+		[] IPA_RSL[i].receive(tr_ASP_RSL_UD(tr_RSL_PAGING_CMD(mi))) {
 			setverdict(fail, "Paging on BTS ", i, " which is not part of ", bts_ids);
 			}
 		[] IPA_RSL[i].receive { repeat; }
@@ -1524,7 +1518,7 @@
 	T.start;
 	T_retrans.start;
 	alt {
-	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_PAGING_CMD(?))) {
+	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(tr_RSL_PAGING_CMD(?))) {
 		setverdict(fail, "Received PAGING after LOAD_IND(0)");
 		mtc.stop;
 		}
@@ -1607,15 +1601,15 @@
 	/* Wait for 3 seconds if any more PAGING CMD are received on RSL */
 	T.start;
 	alt {
-	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_PAGING_CMD(?))) {
+	[] IPA_RSL[0].receive(tr_ASP_RSL_UD(tr_RSL_PAGING_CMD(?))) {
 		setverdict(fail, "Received PAGING after A-RESET");
 		mtc.stop;
 		}
-	[] IPA_RSL[1].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_PAGING_CMD(?))) {
+	[] IPA_RSL[1].receive(tr_ASP_RSL_UD(tr_RSL_PAGING_CMD(?))) {
 		setverdict(fail, "Received PAGING after A-RESET");
 		mtc.stop;
 		}
-	[] IPA_RSL[2].receive(tr_ASP_RSL_UD(IPAC_PROTO_RSL_TRX0, tr_RSL_PAGING_CMD(?))) {
+	[] IPA_RSL[2].receive(tr_ASP_RSL_UD(tr_RSL_PAGING_CMD(?))) {
 		setverdict(fail, "Received PAGING after A-RESET");
 		mtc.stop;
 		}