diff --git a/library/BSSGP_Emulation.ttcn b/library/BSSGP_Emulation.ttcn
index c60868e..22c2f09 100644
--- a/library/BSSGP_Emulation.ttcn
+++ b/library/BSSGP_Emulation.ttcn
@@ -571,15 +571,17 @@
 	}
 
 
+	/* ConnHdlr sends BSSGP on BVCI=0 port: forward it to BSSGP Codec Port */
 	[] BSSGP_SP_SIG.receive(PDU_BSSGP:?)-> value bs_pdu sender vc_conn {
 		BSCP.send(f_BnsUdReq(bs_pdu, 0));
 	}
 
-	/* pass virtually any PDU from user to NS-UNITDATA PDU on network */
+	/* ConnHdlr sends BSSGP on BVCI=PTP port: forward it to BSSGP Codec Port */
 	[] BSSGP_SP.receive(PDU_BSSGP:?) -> value bs_pdu sender vc_conn {
 		BSCP.send(f_BnsUdReq(bs_pdu, g_cfg.bvci));
 	}
 
+	/* ConnHdlr sends L3: Encode and send as UL_UD / DL_UD */
 	[g_cfg.sgsn_role] BSSGP_SP.receive(PDU_L3_SGSN_MS:?) -> value l3_mt sender vc_conn {
 		var integer idx := f_tbl_idx_by_comp(vc_conn);
 		var octetstring l3_enc := enc_PDU_L3_SGSN_MS(l3_mt);