diff --git a/src/mme/emm_sm.c b/src/mme/emm_sm.c
index 22506ba9a..597686950 100644
--- a/src/mme/emm_sm.c
+++ b/src/mme/emm_sm.c
@@ -8,7 +8,7 @@
 #include "emm_handler.h"
 #include "mme_s6a_handler.h"
 
-void emm_state_initial(emm_sm_t *s, event_t *e)
+void emm_state_initial(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
 
@@ -17,14 +17,14 @@ void emm_state_initial(emm_sm_t *s, event_t *e)
     FSM_TRAN(s, &emm_state_operational);
 }
 
-void emm_state_final(emm_sm_t *s, event_t *e)
+void emm_state_final(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
 
     mme_sm_trace(1, e);
 }
 
-void emm_state_operational(emm_sm_t *s, event_t *e)
+void emm_state_operational(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");
@@ -104,7 +104,7 @@ void emm_state_operational(emm_sm_t *s, event_t *e)
     }
 }
 
-void emm_state_exception(emm_sm_t *s, event_t *e)
+void emm_state_exception(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");
diff --git a/src/mme/esm_sm.c b/src/mme/esm_sm.c
index 3e1643c72..efbed16d8 100644
--- a/src/mme/esm_sm.c
+++ b/src/mme/esm_sm.c
@@ -7,7 +7,7 @@
 #include "mme_event.h"
 #include "esm_handler.h"
 
-void esm_state_initial(esm_sm_t *s, event_t *e)
+void esm_state_initial(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
 
@@ -16,14 +16,14 @@ void esm_state_initial(esm_sm_t *s, event_t *e)
     FSM_TRAN(s, &esm_state_operational);
 }
 
-void esm_state_final(esm_sm_t *s, event_t *e)
+void esm_state_final(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
 
     mme_sm_trace(1, e);
 }
 
-void esm_state_operational(esm_sm_t *s, event_t *e)
+void esm_state_operational(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");
@@ -81,7 +81,7 @@ void esm_state_operational(esm_sm_t *s, event_t *e)
     }
 }
 
-void esm_state_exception(esm_sm_t *s, event_t *e)
+void esm_state_exception(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");
diff --git a/src/mme/mme_context.c b/src/mme/mme_context.c
index beedb0db2..d846b79e9 100644
--- a/src/mme/mme_context.c
+++ b/src/mme/mme_context.c
@@ -197,9 +197,8 @@ mme_enb_t* mme_enb_add(net_sock_t *s1ap_sock)
     list_init(&enb->ue_list);
     list_append(&self.enb_list, enb);
 
-    fsm_create((fsm_t*)&enb->s1ap_sm, 
-            s1ap_state_initial, s1ap_state_final);
-    fsm_init((fsm_t*)&enb->s1ap_sm, 0);
+    fsm_create(&enb->sm, s1ap_state_initial, s1ap_state_final);
+    fsm_init(&enb->sm, 0);
     
     return enb;
 }
@@ -208,8 +207,8 @@ status_t mme_enb_remove(mme_enb_t *enb)
 {
     d_assert(enb, return CORE_ERROR, "Null param");
 
-    fsm_final((fsm_t*)&enb->s1ap_sm, 0);
-    fsm_clear((fsm_t*)&enb->s1ap_sm);
+    fsm_final(&enb->sm, 0);
+    fsm_clear(&enb->sm);
 
     mme_ue_remove_in_enb(enb);
 
@@ -374,9 +373,8 @@ mme_ue_t* mme_ue_add(mme_enb_t *enb)
     list_init(&ue->esm_list);
     list_append(&enb->ue_list, ue);
 
-    fsm_create((fsm_t*)&ue->emm_sm, 
-            emm_state_initial, emm_state_final);
-    fsm_init((fsm_t*)&ue->emm_sm, 0);
+    fsm_create(&ue->sm, emm_state_initial, emm_state_final);
+    fsm_init(&ue->sm, 0);
     
     return ue;
 }
@@ -387,8 +385,8 @@ status_t mme_ue_remove(mme_ue_t *ue)
     d_assert(ue, return CORE_ERROR, "Null param");
     d_assert(ue->enb, return CORE_ERROR, "Null param");
 
-    fsm_final((fsm_t*)&ue->emm_sm, 0);
-    fsm_clear((fsm_t*)&ue->emm_sm);
+    fsm_final(&ue->sm, 0);
+    fsm_clear(&ue->sm);
 
     mme_esm_remove_all(ue);
 
@@ -509,9 +507,8 @@ mme_esm_t* mme_esm_add(mme_ue_t *ue, c_uint8_t pti)
 
     list_append(&ue->esm_list, esm);
     
-    fsm_create((fsm_t*)&esm->sm, 
-            esm_state_initial, esm_state_final);
-    fsm_init((fsm_t*)&esm->sm, 0);
+    fsm_create(&esm->sm, esm_state_initial, esm_state_final);
+    fsm_init(&esm->sm, 0);
 
     return esm;
 }
@@ -521,8 +518,8 @@ status_t mme_esm_remove(mme_esm_t *esm)
     d_assert(esm, return CORE_ERROR, "Null param");
     d_assert(esm->ue, return CORE_ERROR, "Null param");
     
-    fsm_final((fsm_t*)&esm->sm, 0);
-    fsm_clear((fsm_t*)&esm->sm);
+    fsm_final(&esm->sm, 0);
+    fsm_clear(&esm->sm);
 
     list_remove(&esm->ue->esm_list, esm);
     index_free(&mme_esm_pool, esm);
diff --git a/src/mme/mme_context.h b/src/mme/mme_context.h
index e137756f1..bb6504c0a 100644
--- a/src/mme/mme_context.h
+++ b/src/mme/mme_context.h
@@ -84,10 +84,9 @@ typedef struct _mme_sgw_t {
 typedef struct _mme_enb_t {
     lnode_t         node;   /**< A node of list_t */
     index_t         index;  /**< Index key */
+    fsm_t           sm;
 
     c_uint32_t      enb_id; /** eNB_ID received from eNB */
-
-    s1ap_sm_t       s1ap_sm;
     net_sock_t      *s1ap_sock;
 
     list_t          ue_list;
@@ -97,9 +96,9 @@ typedef struct _mme_enb_t {
 typedef struct _mme_ue_t {
     lnode_t         node;   /**< A node of list_t */
     index_t         index;  /**< Index key */
+    fsm_t           sm;
 
     /* State Machine */
-    emm_sm_t        emm_sm;
 
     /* UE identity */
     c_uint32_t      enb_ue_s1ap_id; /** eNB-UE-S1AP-ID received from eNB */
@@ -153,11 +152,10 @@ typedef struct _mme_ue_t {
 typedef struct _mme_esm_t {
     lnode_t         node;   /**< A node of list_t */
     index_t         index;  /**< Index key */
+    fsm_t           sm;
 
     c_uint8_t       pti;    /** Procedure Trasaction Identity */
 
-    esm_sm_t        sm;
-
     mme_ue_t        *ue;
 } mme_esm_t;
 
diff --git a/src/mme/mme_init.c b/src/mme/mme_init.c
index 7131156ca..196d29267 100644
--- a/src/mme/mme_init.c
+++ b/src/mme/mme_init.c
@@ -39,7 +39,7 @@ void mme_terminate(void)
 void *THREAD_FUNC mme_sm_main(thread_id id, void *data)
 {
     event_t event;
-    mme_sm_t mme_sm;
+    fsm_t mme_sm;
     c_time_t prev_tm, now_tm;
     status_t rv;
 
@@ -52,9 +52,8 @@ void *THREAD_FUNC mme_sm_main(thread_id id, void *data)
     gtp_xact_init(&mme_self()->gtp_xact_ctx, 
             &mme_self()->tm_service, EVT_TM_MME_S11_T3);
 
-    fsm_create(&mme_sm.fsm, mme_state_initial, mme_state_final);
-    d_assert(&mme_sm.fsm, return NULL, "MME state machine creation failed");
-    fsm_init((fsm_t*)&mme_sm, 0);
+    fsm_create(&mme_sm, mme_state_initial, mme_state_final);
+    fsm_init(&mme_sm, 0);
 
     prev_tm = time_now();
 
@@ -81,11 +80,11 @@ void *THREAD_FUNC mme_sm_main(thread_id id, void *data)
             continue;
         }
 
-        fsm_dispatch((fsm_t*)&mme_sm, (fsm_event_t*)&event);
+        fsm_dispatch(&mme_sm, (fsm_event_t*)&event);
     }
 
-    fsm_final((fsm_t*)&mme_sm, 0);
-    fsm_clear((fsm_t*)&mme_sm);
+    fsm_final(&mme_sm, 0);
+    fsm_clear(&mme_sm);
 
     gtp_xact_final();
     event_delete(mme_self()->queue_id);
diff --git a/src/mme/mme_sm.c b/src/mme/mme_sm.c
index 486d3cabf..894c44b20 100644
--- a/src/mme/mme_sm.c
+++ b/src/mme/mme_sm.c
@@ -10,7 +10,7 @@
 #include "nas_security.h"
 #include "mme_s11_path.h"
 
-void mme_state_initial(mme_sm_t *s, event_t *e)
+void mme_state_initial(fsm_t *s, event_t *e)
 {
     mme_sm_trace(1, e);
 
@@ -19,14 +19,14 @@ void mme_state_initial(mme_sm_t *s, event_t *e)
     FSM_TRAN(s, &mme_state_operational);
 }
 
-void mme_state_final(mme_sm_t *s, event_t *e)
+void mme_state_final(fsm_t *s, event_t *e)
 {
     mme_sm_trace(1, e);
 
     d_assert(s, return, "Null param");
 }
 
-void mme_state_operational(mme_sm_t *s, event_t *e)
+void mme_state_operational(fsm_t *s, event_t *e)
 {
     status_t rv;
     char buf[INET_ADDRSTRLEN];
@@ -131,14 +131,14 @@ void mme_state_operational(mme_sm_t *s, event_t *e)
             d_assert(index, pkbuf_free(pkbuf); break, "Null param");
             d_assert(enb = mme_enb_find(index),
                     pkbuf_free(pkbuf); break, "No eNB context");
-            d_assert(FSM_STATE(&enb->s1ap_sm), 
+            d_assert(FSM_STATE(&enb->sm), 
                     pkbuf_free(pkbuf); break, "No S1AP State Machine");
 
             d_assert(s1ap_decode_pdu(&message, pkbuf) == CORE_OK,
                     pkbuf_free(pkbuf); break, "Can't decode S1AP_PDU");
 
             event_set_param3(e, (c_uintptr_t)&message);
-            fsm_dispatch((fsm_t*)&enb->s1ap_sm, (fsm_event_t*)e);
+            fsm_dispatch(&enb->sm, (fsm_event_t*)e);
 
             s1ap_free_pdu(&message);
             pkbuf_free(pkbuf);
@@ -155,14 +155,14 @@ void mme_state_operational(mme_sm_t *s, event_t *e)
             d_assert(index, pkbuf_free(pkbuf); break, "Null param");
             ue = mme_ue_find(index);
             d_assert(ue, pkbuf_free(pkbuf); break, "No UE context");
-            d_assert(FSM_STATE(&ue->emm_sm), 
+            d_assert(FSM_STATE(&ue->sm), 
                     pkbuf_free(pkbuf); break, "No EMM State Machine");
 
             d_assert(nas_security_decode(&message, ue, pkbuf) == CORE_OK,
                     pkbuf_free(pkbuf); break, "Can't decode NAS_EMM");
 
             event_set_param3(e, (c_uintptr_t)&message);
-            fsm_dispatch((fsm_t*)&ue->emm_sm, (fsm_event_t*)e);
+            fsm_dispatch(&ue->sm, (fsm_event_t*)e);
 
             pkbuf_free(pkbuf);
             break;
@@ -187,7 +187,7 @@ void mme_state_operational(mme_sm_t *s, event_t *e)
                     pkbuf_free(pkbuf); break, "Can't decode NAS_ESM");
 
             event_set_param3(e, (c_uintptr_t)&message);
-            fsm_dispatch((fsm_t*)&esm->sm, (fsm_event_t*)e);
+            fsm_dispatch(&esm->sm, (fsm_event_t*)e);
 
             pkbuf_free(pkbuf);
             break;
diff --git a/src/mme/mme_sm.h b/src/mme/mme_sm.h
index 5b1c7558b..caeb0d14e 100644
--- a/src/mme/mme_sm.h
+++ b/src/mme/mme_sm.h
@@ -9,41 +9,25 @@
 extern "C" {
 #endif /* __cplusplus */
 
-typedef struct _mme_sm_t {
-    fsm_t fsm;
-} mme_sm_t;
+void mme_state_initial(fsm_t *s, event_t *e);
+void mme_state_final(fsm_t *s, event_t *e);
+void mme_state_operational(fsm_t *s, event_t *e);
+void mme_state_exception(fsm_t *s, event_t *e);
 
-void mme_state_initial(mme_sm_t *s, event_t *e);
-void mme_state_final(mme_sm_t *s, event_t *e);
-void mme_state_operational(mme_sm_t *s, event_t *e);
-void mme_state_exception(mme_sm_t *s, event_t *e);
+void s1ap_state_initial(fsm_t *s, event_t *e);
+void s1ap_state_final(fsm_t *s, event_t *e);
+void s1ap_state_operational(fsm_t *s, event_t *e);
+void s1ap_state_exception(fsm_t *s, event_t *e);
 
-typedef struct _s1ap_sm_t {
-    fsm_t fsm;
-} s1ap_sm_t;
+void emm_state_initial(fsm_t *s, event_t *e);
+void emm_state_final(fsm_t *s, event_t *e);
+void emm_state_operational(fsm_t *s, event_t *e);
+void emm_state_exception(fsm_t *s, event_t *e);
 
-void s1ap_state_initial(s1ap_sm_t *s, event_t *e);
-void s1ap_state_final(s1ap_sm_t *s, event_t *e);
-void s1ap_state_operational(s1ap_sm_t *s, event_t *e);
-void s1ap_state_exception(s1ap_sm_t *s, event_t *e);
-
-typedef struct _emm_sm_t {
-    fsm_t fsm;
-} emm_sm_t;
-
-void emm_state_initial(emm_sm_t *s, event_t *e);
-void emm_state_final(emm_sm_t *s, event_t *e);
-void emm_state_operational(emm_sm_t *s, event_t *e);
-void emm_state_exception(emm_sm_t *s, event_t *e);
-
-typedef struct _esm_sm_t {
-    fsm_t fsm;
-} esm_sm_t;
-
-void esm_state_initial(esm_sm_t *s, event_t *e);
-void esm_state_final(esm_sm_t *s, event_t *e);
-void esm_state_operational(esm_sm_t *s, event_t *e);
-void esm_state_exception(esm_sm_t *s, event_t *e);
+void esm_state_initial(fsm_t *s, event_t *e);
+void esm_state_final(fsm_t *s, event_t *e);
+void esm_state_operational(fsm_t *s, event_t *e);
+void esm_state_exception(fsm_t *s, event_t *e);
 
 #define mme_sm_print(__pe) \
     d_print("%s(): %s\n", __func__, mme_event_get_name(__pe))
diff --git a/src/mme/s1ap_sm.c b/src/mme/s1ap_sm.c
index 8558fe6e1..cb75cbbd6 100644
--- a/src/mme/s1ap_sm.c
+++ b/src/mme/s1ap_sm.c
@@ -7,7 +7,7 @@
 #include "s1ap_build.h"
 #include "s1ap_handler.h"
 
-void s1ap_state_initial(s1ap_sm_t *s, event_t *e)
+void s1ap_state_initial(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
 
@@ -16,14 +16,14 @@ void s1ap_state_initial(s1ap_sm_t *s, event_t *e)
     FSM_TRAN(s, &s1ap_state_operational);
 }
 
-void s1ap_state_final(s1ap_sm_t *s, event_t *e)
+void s1ap_state_final(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
 
     mme_sm_trace(1, e);
 }
 
-void s1ap_state_operational(s1ap_sm_t *s, event_t *e)
+void s1ap_state_operational(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");
@@ -117,7 +117,7 @@ void s1ap_state_operational(s1ap_sm_t *s, event_t *e)
     }
 }
 
-void s1ap_state_exception(s1ap_sm_t *s, event_t *e)
+void s1ap_state_exception(fsm_t *s, event_t *e)
 {
     d_assert(s, return, "Null param");
     d_assert(e, return, "Null param");