diff --git a/bsc-nat/MSC_ConnectionHandler.ttcn b/bsc-nat/MSC_ConnectionHandler.ttcn
index 383b67b..8635a29 100644
--- a/bsc-nat/MSC_ConnectionHandler.ttcn
+++ b/bsc-nat/MSC_ConnectionHandler.ttcn
@@ -59,6 +59,7 @@
 	unitdata_cb := refers(UnitdataCallback),
 	decode_dtap := false,
 	role_ms := false,
+	protocol := RAN_PROTOCOL_BSSAP,
 	sccp_addr_local := omit,
 	sccp_addr_peer := omit
 }