diff --git a/bsc-nat/BSC_MS_ConnectionHandler.ttcn b/bsc-nat/BSC_MS_ConnectionHandler.ttcn
index 63d0451..e52b678 100644
--- a/bsc-nat/BSC_MS_ConnectionHandler.ttcn
+++ b/bsc-nat/BSC_MS_ConnectionHandler.ttcn
@@ -53,6 +53,7 @@
 	unitdata_cb := refers(UnitdataCallback),
 	decode_dtap := false,
 	role_ms := true,
+	protocol := RAN_PROTOCOL_BSSAP,
 	sccp_addr_local := omit,
 	sccp_addr_peer := omit
 }