diff --git a/include/openbsc/osmo_msc.h b/include/openbsc/osmo_msc.h
index beb3f5e..0642c91 100644
--- a/include/openbsc/osmo_msc.h
+++ b/include/openbsc/osmo_msc.h
@@ -3,9 +3,76 @@
 #ifndef OSMO_MSC_H
 #define OSMO_MSC_H
 
+#include <osmocom/core/fsm.h>
+#include <osmocom/gsm/gsup.h>
+
+#include <openbsc/gsm_data.h>
+
 #include "bsc_api.h"
 
+#define MSC_HLR_REMOTE_IP_DEFAULT "127.0.0.1"
+#define MSC_HLR_REMOTE_PORT_DEFAULT OSMO_GSUP_PORT
+
+enum subscr_conn_fsm_event {
+	/* Mark 0 as invalid to catch uninitialized vars */
+	SUBSCR_CONN_E_INVALID = 0,
+	/* Timeout on connection establishment starts */
+	SUBSCR_CONN_E_START,
+	/* LU or Process Access FSM has determined that this conn is good */
+	SUBSCR_CONN_E_ACCEPTED,
+	/* received first reply from MS in "real" CC, SMS, USSD communication */
+	SUBSCR_CONN_E_COMMUNICATING,
+	/* Some async action has completed, check again whether all is done */
+	SUBSCR_CONN_E_BUMP,
+	/* MS/BTS/BSC originated close request */
+	SUBSCR_CONN_E_MO_CLOSE,
+	/* MSC originated close request, e.g. failed authentication */
+	SUBSCR_CONN_E_CN_CLOSE,
+};
+
+enum subscr_conn_fsm_state {
+	SUBSCR_CONN_S_INIT,
+	SUBSCR_CONN_S_NEW,
+	SUBSCR_CONN_S_ACCEPTED,
+	SUBSCR_CONN_S_COMMUNICATING,
+	SUBSCR_CONN_S_RELEASED,
+};
+
+enum subscr_conn_from {
+	SUBSCR_CONN_FROM_INVALID,
+	SUBSCR_CONN_FROM_LU,
+	SUBSCR_CONN_FROM_CM_SERVICE_REQ,
+	SUBSCR_CONN_FROM_PAGING_RESP,
+};
+
+extern const struct value_string subscr_conn_from_names[];
+static inline const char *subscr_conn_from_name(enum subscr_conn_from val)
+{
+	return get_value_string(subscr_conn_from_names, val);
+}
+
+
 struct bsc_api *msc_bsc_api();
-void msc_release_connection(struct gsm_subscriber_connection *conn);
+
+int msc_create_conn_fsm(struct gsm_subscriber_connection *conn, const char *id);
+
+int msc_vlr_alloc(struct gsm_network *net);
+int msc_vlr_start(struct gsm_network *net);
+
+void msc_subscr_conn_init(void);
+bool msc_subscr_conn_is_accepted(struct gsm_subscriber_connection *conn);
+void msc_subscr_conn_communicating(struct gsm_subscriber_connection *conn);
+void msc_subscr_conn_close(struct gsm_subscriber_connection *conn,
+			   uint32_t cause);
+
+#define msc_subscr_conn_get(conn) \
+	_msc_subscr_conn_get(conn, __BASE_FILE__, __LINE__)
+#define msc_subscr_conn_put(conn) \
+	_msc_subscr_conn_put(conn, __BASE_FILE__, __LINE__)
+struct gsm_subscriber_connection *
+_msc_subscr_conn_get(struct gsm_subscriber_connection *conn,
+		     const char *file, int line);
+void _msc_subscr_conn_put(struct gsm_subscriber_connection *conn,
+			  const char *file, int line);
 
 #endif