diff --git a/src/slotmap.h b/src/slotmap.h
index 92eb6f4..27d7e1b 100644
--- a/src/slotmap.h
+++ b/src/slotmap.h
@@ -4,6 +4,8 @@
 #include <pthread.h>
 #include <osmocom/core/linuxlist.h>
 
+#define REMSIM_SERVER 1
+
 struct bank_slot {
 	uint16_t bank_id;
 	uint16_t slot_nr;
@@ -30,14 +32,33 @@
 		return false;
 }
 
+enum slot_mapping_state {
+	SLMAP_S_NEW,		/* created; not yet sent to bankd */
+	SLMAP_S_UNACKNOWLEDGED,	/* created + sent to bankd but not yet acknowledge by bankd */
+	SLMAP_S_ACTIVE,		/* fully active map; acknowledged by bankd */
+	SLMAP_S_DELETING,	/* we were asked to delete it; bankd hasn't confirmed yet */
+};
+extern const struct value_string slot_map_state_name[];
+static inline const char *slotmap_state_name(enum slot_mapping_state st)
+{
+	return get_value_string(slot_map_state_name, st);
+}
+
 /* slot mappings are created / removed by the server */
 struct slot_mapping {
 	/* global lits of bankd slot mappings */
 	struct llist_head list;
+	struct slotmaps *maps;
+
 	/* slot on bank side */
 	struct bank_slot bank;
 	/* slot on client side */
 	struct client_slot client;
+
+#ifdef REMSIM_SERVER
+	struct llist_head bank_list;
+	enum slot_mapping_state state;
+#endif
 };
 
 /* collection of slot mappings */
@@ -60,3 +81,11 @@
 
 /* initialize the entire map collection */
 struct slotmaps *slotmap_init(void *ctx);
+
+#ifdef REMSIM_SERVER
+void _slotmap_state_change(struct slot_mapping *map, enum slot_mapping_state new_state,
+			   struct llist_head *new_bank_list);
+/* thread-safe way to change the state of given slot map */
+void slotmap_state_change(struct slot_mapping *map, enum slot_mapping_state new_state,
+			  struct llist_head *new_bank_list);
+#endif