code cleanup and fixes mainly rbuf

11 files changed, 555 insertions, 488 deletions

diff --git a/ecp/src/TODO b/ecp/src/TODO
index 982e382..01c2a28 100644
--- a/ecp/src/TODO
+++ b/ecp/src/TODO
@@ -7,5 +7,3 @@
 rbuf:
 - implement _wait variants of open / send
 - msgq should subtract ECP_MAX_MTYPE_SYS from mtype (make ECPConnMsgQ smaller)
-- consider adding one buffer for all msgs (frag. issue)
-
diff --git a/ecp/src/core.c b/ecp/src/core.c
index a8f8f01..90ee925 100644
--- a/ecp/src/core.c
+++ b/ecp/src/core.c
@@ -311,7 +311,6 @@ static ECPDHKey *conn_dhkey_get(ECPConnection *conn, unsigned char idx) {
 }
 
 static int conn_dhkey_new_pair(ECPConnection *conn, ECPDHKey *key) {
-    /* called when client makes new key pair */
     ECPSocket *sock = conn->sock;
 
     conn->key_curr = conn->key_curr == ECP_ECDH_IDX_INV ? 0 : (conn->key_curr+1) % ECP_MAX_CONN_KEY;
@@ -349,8 +348,8 @@ static void conn_dhkey_del_pair(ECPConnection *conn, unsigned char idx) {
     conn->key_idx_map[idx] = ECP_ECDH_IDX_INV;
 }
 
+/* remote client obtained our key */
 static int conn_dhkey_new_pub_local(ECPConnection *conn, unsigned char idx) {
-    // Remote obtained our key
     unsigned char new = conn->key_idx_curr == ECP_ECDH_IDX_INV ? 0 : (conn->key_idx_curr+1) % ECP_MAX_NODE_KEY;
     int i;
 
@@ -367,8 +366,8 @@ static int conn_dhkey_new_pub_local(ECPConnection *conn, unsigned char idx) {
     return ECP_OK;
 }
 
+/* this client obtained remote key */
 static int conn_dhkey_new_pub_remote(ECPConnection *conn, unsigned char idx, unsigned char *public) {
-    // We obtained remote key
     ECPSocket *sock = conn->sock;
     ECPDHRKeyBucket *remote = &conn->remote;
     unsigned char new = remote->key_curr == ECP_ECDH_IDX_INV ? 0 : (remote->key_curr+1) % ECP_MAX_NODE_KEY;
@@ -649,7 +648,7 @@ int ecp_conn_open(ECPConnection *conn, ECPNode *node) {
     return ECP_OK;
 }
 
-void _ecp_conn_close(ECPConnection *conn) {
+static void conn_close(ECPConnection *conn) {
     ECPContext *ctx = conn->sock->ctx;
 
     if (ecp_conn_is_inb(conn) && conn->parent) {
@@ -672,7 +671,7 @@ int ecp_conn_close(ECPConnection *conn) {
 
     if (refcount) return ECP_ERR_BUSY;
 
-    _ecp_conn_close(conn);
+    conn_close(conn);
     return ECP_OK;
 }
 
@@ -737,7 +736,7 @@ void ecp_conn_refcount_dec(ECPConnection *conn) {
     pthread_mutex_unlock(&conn->mutex);
 #endif
 
-    if (!is_reg && (refcount == 0)) _ecp_conn_close(conn);
+    if (!is_reg && (refcount == 0)) conn_close(conn);
 }
 
 int ecp_conn_handler_init(ECPConnHandler *handler) {
@@ -751,7 +750,7 @@ int ecp_conn_handler_init(ECPConnHandler *handler) {
 #ifdef ECP_WITH_RBUF
     handler->msg[ECP_MTYPE_RBACK] = ecp_rbuf_handle_ack;
     handler->msg[ECP_MTYPE_RBFLUSH] = ecp_rbuf_handle_flush;
-    handler->msg[ECP_MTYPE_RBFLUSH_PTS] = ecp_rbuf_handle_flush_pts;
+    handler->msg[ECP_MTYPE_RBTIMER] = ecp_rbuf_handle_timer;
 #endif
     return ECP_OK;
 }
@@ -867,7 +866,7 @@ static ssize_t _conn_send_kget(ECPConnection *conn, ECPTimerItem *ti) {
     payload.size = ECP_SIZE_PLD_BUF(0, ECP_MTYPE_KGET_REQ, conn);
 
     ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_KGET_REQ);
-    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, NULL, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_KGET_REQ), 0, ti);
+    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_KGET_REQ), 0, ti);
 }
 
 static ssize_t _conn_send_kput(ECPConnection *conn, ECPTimerItem *ti) {
@@ -903,7 +902,7 @@ static ssize_t _conn_send_dir(ECPConnection *conn, ECPTimerItem *ti) {
     payload.size = ECP_SIZE_PLD_BUF(0, ECP_MTYPE_DIR_REQ, conn);
 
     ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_DIR_REQ);
-    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, NULL, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_DIR_REQ), 0, ti);
+    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_DIR_REQ), 0, ti);
 }
 
 ssize_t ecp_conn_send_open(ECPConnection *conn) {
@@ -1114,7 +1113,7 @@ ssize_t ecp_conn_handle_msg(ECPConnection *conn, ecp_seq_t seq, unsigned char *m
 
     while (rem_size) {
         _rv = ecp_msg_get_type(msg, rem_size, &mtype);
-        if (_rv) return ECP_ERR_MIN_MSG;
+        if (_rv) return ECP_ERR;
         if ((mtype & ECP_MTYPE_MASK) >= ECP_MAX_MTYPE) return ECP_ERR_MAX_MTYPE;
 
         ecp_timer_pop(conn, mtype);
@@ -1133,7 +1132,7 @@ ssize_t ecp_conn_handle_msg(ECPConnection *conn, ecp_seq_t seq, unsigned char *m
         }
 
         content = ecp_msg_get_content(msg, rem_size);
-        if (content == NULL) return ECP_ERR_MIN_MSG;
+        if (content == NULL) return ECP_ERR;
         rem_size -= content - msg;
 
         handler = ecp_conn_get_msg_handler(conn, mtype & ECP_MTYPE_MASK);
@@ -1209,7 +1208,6 @@ ssize_t ecp_sock_handle_kget(ECPSocket *sock, ECPNetAddr *addr, ECPConnection *p
     return msg_size;
 }
 
-
 ssize_t _ecp_pack(ECPContext *ctx, unsigned char *packet, size_t pkt_size, ECPPktMeta *pkt_meta, unsigned char *payload, size_t pld_size) {
     ssize_t rv;
     unsigned char s_idx, c_idx;
@@ -1246,7 +1244,7 @@ ssize_t ecp_pack(ECPContext *ctx, ECPConnection *parent, ECPBuffer *packet, ECPP
 }
 #endif
 
-ssize_t _ecp_pack_conn(ECPConnection *conn, unsigned char *packet, size_t pkt_size, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, unsigned char *payload, size_t pld_size, ECPNetAddr *addr) {
+ssize_t _ecp_pack_conn(ECPConnection *conn, unsigned char *packet, size_t pkt_size, unsigned char s_idx, unsigned char c_idx, unsigned char *payload, size_t pld_size, ECPNetAddr *addr, ECPSeqItem *si) {
     ECPPktMeta pkt_meta;
     int rv;
     ssize_t _rv;
@@ -1254,6 +1252,7 @@ ssize_t _ecp_pack_conn(ECPConnection *conn, unsigned char *packet, size_t pkt_si
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_lock(&conn->mutex);
 #endif
+
     if (s_idx == ECP_ECDH_IDX_INV) {
         if (ecp_conn_is_outb(conn)) {
             if (conn->remote.key_curr != ECP_ECDH_IDX_INV) s_idx = conn->remote.key[conn->remote.key_curr].idx;
@@ -1326,11 +1325,11 @@ ssize_t _ecp_pack_conn(ECPConnection *conn, unsigned char *packet, size_t pkt_si
 }
 
 #ifndef ECP_WITH_VCONN
-ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr) {
+ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr, ECPSeqItem *si) {
     if ((packet == NULL) || (packet->buffer == NULL)) return ECP_ERR;
     if ((payload == NULL) || (payload->buffer == NULL)) return ECP_ERR;
 
-    return _ecp_pack_conn(conn, packet->buffer, packet->size, s_idx, c_idx, si, payload->buffer, pld_size, addr);
+    return _ecp_pack_conn(conn, packet->buffer, packet->size, s_idx, c_idx, payload->buffer, pld_size, addr, si);
 }
 #endif
 
@@ -1683,13 +1682,13 @@ int ecp_msg_defrag(ECPFragIter *iter, ecp_seq_t seq, unsigned char mtype, unsign
     int rv;
 
     rv = ecp_msg_get_frag(msg_in, msg_in_size, &frag_cnt, &frag_tot, &frag_size);
-    if (rv) return ECP_ERR_MIN_MSG;
+    if (rv) return ECP_ERR;
 
     content = ecp_msg_get_content(msg_in, msg_in_size);
-    if (content == NULL) return ECP_ERR_MIN_MSG;
+    if (content == NULL) return ECP_ERR;
 
     msg_size = msg_in_size - (content - msg_in);
-    if (msg_size == 0) return ECP_ERR_MIN_MSG;
+    if (msg_size == 0) return ECP_ERR;
 
     if (iter->msg_size && (iter->seq + frag_cnt != seq)) ecp_frag_iter_reset(iter);
 
@@ -1725,6 +1724,8 @@ int ecp_msg_defrag(ECPFragIter *iter, ecp_seq_t seq, unsigned char mtype, unsign
 }
 
 int ecp_pld_get_type(unsigned char *payload, size_t pld_size, unsigned char *mtype) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return ECP_ERR;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
@@ -1732,6 +1733,8 @@ int ecp_pld_get_type(unsigned char *payload, size_t pld_size, unsigned char *mty
 }
 
 int ecp_pld_set_type(unsigned char *payload, size_t pld_size, unsigned char mtype) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return ECP_ERR;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
@@ -1739,6 +1742,8 @@ int ecp_pld_set_type(unsigned char *payload, size_t pld_size, unsigned char mtyp
 }
 
 int ecp_pld_get_frag(unsigned char *payload, size_t pld_size, unsigned char *frag_cnt, unsigned char *frag_tot, uint16_t *frag_size) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return ECP_ERR;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
@@ -1746,6 +1751,8 @@ int ecp_pld_get_frag(unsigned char *payload, size_t pld_size, unsigned char *fra
 }
 
 int ecp_pld_set_frag(unsigned char *payload, size_t pld_size, unsigned char frag_cnt, unsigned char frag_tot, uint16_t frag_size) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return ECP_ERR;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
@@ -1753,6 +1760,8 @@ int ecp_pld_set_frag(unsigned char *payload, size_t pld_size, unsigned char frag
 }
 
 int ecp_pld_get_pts(unsigned char *payload, size_t pld_size, ecp_pts_t *pts) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return ECP_ERR;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
@@ -1760,6 +1769,8 @@ int ecp_pld_get_pts(unsigned char *payload, size_t pld_size, ecp_pts_t *pts) {
 }
 
 int ecp_pld_set_pts(unsigned char *payload, size_t pld_size, ecp_pts_t pts) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return ECP_ERR;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
@@ -1767,18 +1778,20 @@ int ecp_pld_set_pts(unsigned char *payload, size_t pld_size, ecp_pts_t pts) {
 }
 
 unsigned char *ecp_pld_get_buf(unsigned char *payload, size_t pld_size) {
+    if (pld_size < ECP_SIZE_PLD_HDR) return NULL;
+
     payload += ECP_SIZE_PLD_HDR;
     pld_size -= ECP_SIZE_PLD_HDR;
 
     return ecp_msg_get_content(payload, pld_size);
 }
 
-static ssize_t pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti) {
+ssize_t __ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti, ECPSeqItem *si) {
     ECPSocket *sock = conn->sock;
     ECPNetAddr addr;
     ssize_t rv;
 
-    rv = ecp_pack_conn(conn, packet, s_idx, c_idx, si, payload, pld_size, &addr);
+    rv = ecp_pack_conn(conn, packet, s_idx, c_idx, payload, pld_size, &addr, si);
     if (rv < 0) return rv;
 
 #ifdef ECP_WITH_RBUF
@@ -1797,35 +1810,43 @@ static ssize_t pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_
     return ecp_pkt_send(sock, &addr, packet, rv, flags);
 }
 
-ssize_t _ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti) {
 #ifdef ECP_WITH_RBUF
-    if ((si == NULL) && conn->rbuf.send) {
+
+ssize_t _ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti) {
+    if (conn->rbuf.send) {
         ECPSeqItem seq_item;
         int rv;
 
         rv = ecp_seq_item_init(&seq_item);
         if (rv) return rv;
 
-        return pld_send(conn, packet, s_idx, c_idx, &seq_item, payload, pld_size, flags, ti);
+        return __ecp_pld_send(conn, packet, s_idx, c_idx, payload, pld_size, flags, ti, &seq_item);
     }
-#endif
 
-    return pld_send(conn, packet, s_idx, c_idx, NULL, payload, pld_size, flags, ti);
+    return __ecp_pld_send(conn, packet, s_idx, c_idx, payload, pld_size, flags, ti, NULL);
 }
 
+#else
+
+ssize_t _ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti) {
+    return __ecp_pld_send(conn, packet, s_idx, c_idx, payload, pld_size, flags, ti, NULL);
+}
+
+#endif
+
 ssize_t ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, ECPBuffer *payload, size_t pld_size, unsigned char flags) {
-    return _ecp_pld_send(conn, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, NULL, payload, pld_size, flags, NULL);
+    return _ecp_pld_send(conn, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, payload, pld_size, flags, NULL);
 }
 
 ssize_t ecp_pld_send_wtimer(ECPConnection *conn, ECPBuffer *packet, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti) {
-    return _ecp_pld_send(conn, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, NULL, payload, pld_size, flags, ti);
+    return _ecp_pld_send(conn, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, payload, pld_size, flags, ti);
 }
 
 ssize_t ecp_pld_send_tr(ECPSocket *sock, ECPNetAddr *addr, ECPConnection *parent, ECPBuffer *packet, ECPPktMeta *pkt_meta, ECPBuffer *payload, size_t pld_size, unsigned char flags) {
     ECPNetAddr _addr;
     ssize_t rv;
 
-    rv = ecp_pack(sock->ctx, parent, packet, pkt_meta, payload, pld_size, &_addr);
+    rv = ecp_pack(sock->ctx, parent, packet, pkt_meta, payload, pld_size, addr ? NULL : &_addr);
     if (rv < 0) return rv;
 
     return ecp_pkt_send(sock, addr ? addr : &_addr, packet, rv, flags);
@@ -1887,7 +1908,7 @@ ssize_t ecp_send(ECPConnection *conn, unsigned char mtype, unsigned char *conten
             content += frag_size;
             seq_item.seq = seq_start + i;
 
-            _rv = _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, &seq_item, &payload, ECP_SIZE_PLD(frag_size, mtype), 0, NULL);
+            _rv = __ecp_pld_send(conn, &packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, &payload, ECP_SIZE_PLD(frag_size, mtype), 0, NULL, &seq_item);
             if (_rv < 0) return _rv;
 
             rv += _rv;
diff --git a/ecp/src/core.h b/ecp/src/core.h
index bf04947..d842e8b 100644
--- a/ecp/src/core.h
+++ b/ecp/src/core.h
@@ -18,19 +18,14 @@
 #define ECP_ERR_SIZE                -4
 #define ECP_ERR_ITER                -5
 #define ECP_ERR_BUSY                -6
+#define ECP_ERR_EMPTY               -7
+#define ECP_ERR_FULL                -8
 
 #define ECP_ERR_MAX_SOCK_CONN       -10
 #define ECP_ERR_MAX_CTYPE           -11
 #define ECP_ERR_MAX_MTYPE           -12
-#define ECP_ERR_MIN_PKT             -13
-#define ECP_ERR_MAX_PLD             -14
-// XXX ???
-#define ECP_ERR_MIN_MSG             -15
-#define ECP_ERR_MAX_MSG             -16
-//
-#define ECP_ERR_NET_ADDR            -17
-
-#define ECP_ERR_CONN_NOT_FOUND      -20
+#define ECP_ERR_NET_ADDR            -13
+
 #define ECP_ERR_ECDH_KEY_DUP        -21
 #define ECP_ERR_ECDH_IDX            -22
 #define ECP_ERR_ECDH_IDX_LOCAL      -23
@@ -42,7 +37,6 @@
 #define ECP_ERR_RECV                -29
 #define ECP_ERR_SEQ                 -30
 #define ECP_ERR_CLOSED              -31
-#define ECP_ERR_HANDLE              -32
 #define ECP_ERR_NOT_IMPLEMENTED     -99
 
 #define ECP_SIZE_PROTO              2
@@ -98,19 +92,19 @@
 #define ECP_SEND_FLAG_REPLY         0x01
 #define ECP_SEND_FLAG_MORE          0x02
 
-#define ecp_conn_is_inb(conn)     (!((conn)->flags_ro & ECP_CONN_FLAG_OUTB))
-#define ecp_conn_is_outb(conn)      ((conn)->flags_ro & ECP_CONN_FLAG_OUTB)
-#define ecp_conn_is_new(conn)       ((conn)->flags_ro & ECP_CONN_FLAG_NEW)
+#define ecp_conn_is_inb(conn)     (!((conn)->flags_im & ECP_CONN_FLAG_OUTB))
+#define ecp_conn_is_outb(conn)      ((conn)->flags_im & ECP_CONN_FLAG_OUTB)
+#define ecp_conn_is_new(conn)       ((conn)->flags_im & ECP_CONN_FLAG_NEW)
 #define ecp_conn_is_reg(conn)       ((conn)->flags    & ECP_CONN_FLAG_REG)
 #define ecp_conn_is_open(conn)      ((conn)->flags    & ECP_CONN_FLAG_OPEN)
 
-#define ecp_conn_set_outb(conn)     ((conn)->flags_ro |= ECP_CONN_FLAG_OUTB)
-#define ecp_conn_set_new(conn)      ((conn)->flags_ro |= ECP_CONN_FLAG_NEW)
+#define ecp_conn_set_outb(conn)     ((conn)->flags_im |= ECP_CONN_FLAG_OUTB)
+#define ecp_conn_set_new(conn)      ((conn)->flags_im |= ECP_CONN_FLAG_NEW)
 #define ecp_conn_set_reg(conn)      ((conn)->flags    |= ECP_CONN_FLAG_REG)
 #define ecp_conn_set_open(conn)     ((conn)->flags    |= ECP_CONN_FLAG_OPEN)
 
-#define ecp_conn_clr_outb(conn)     ((conn)->flags_ro &= ~ECP_CONN_FLAG_OUTB)
-#define ecp_conn_clr_new(conn)      ((conn)->flags_ro &= ~ECP_CONN_FLAG_NEW)
+#define ecp_conn_clr_outb(conn)     ((conn)->flags_im &= ~ECP_CONN_FLAG_OUTB)
+#define ecp_conn_clr_new(conn)      ((conn)->flags_im &= ~ECP_CONN_FLAG_NEW)
 #define ecp_conn_clr_reg(conn)      ((conn)->flags    &= ~ECP_CONN_FLAG_REG)
 #define ecp_conn_clr_open(conn)     ((conn)->flags    &= ~ECP_CONN_FLAG_OPEN)
 
@@ -224,7 +218,7 @@ typedef struct ECPSeqItem {
 #ifdef ECP_WITH_RBUF
     unsigned char rb_pass;
     unsigned char rb_mtype;
-    unsigned int rb_idx;
+    unsigned short rb_idx;
 #endif
 } ECPSeqItem;
 
@@ -293,7 +287,7 @@ typedef struct ECPSocket {
 typedef struct ECPConnection {
     unsigned char type;
     unsigned char flags;
-    unsigned char flags_ro;
+    unsigned char flags_im;
     unsigned short refcount;
     ecp_seq_t seq_out;
     ecp_seq_t seq_in;
@@ -347,7 +341,6 @@ void ecp_conn_unregister(ECPConnection *conn, unsigned short *refcount);
 
 int ecp_conn_get_dirlist(ECPConnection *conn, ECPNode *node);
 int ecp_conn_open(ECPConnection *conn, ECPNode *node);
-void _ecp_conn_close(ECPConnection *conn);
 int ecp_conn_close(ECPConnection *conn);
 int ecp_conn_reset(ECPConnection *conn);
 void ecp_conn_refcount_inc(ECPConnection *conn);
@@ -377,8 +370,8 @@ ssize_t ecp_sock_handle_kget(ECPSocket *sock, ECPNetAddr *addr, ECPConnection *p
 ssize_t _ecp_pack(ECPContext *ctx, unsigned char *packet, size_t pkt_size, ECPPktMeta *pkt_meta, unsigned char *payload, size_t pld_size);
 ssize_t ecp_pack(ECPContext *ctx, ECPConnection *parent, ECPBuffer *packet, ECPPktMeta *pkt_meta, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr) ;
 
-ssize_t _ecp_pack_conn(ECPConnection *conn, unsigned char *packet, size_t pkt_size, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, unsigned char *payload, size_t pld_size, ECPNetAddr *addr);
-ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr);
+ssize_t _ecp_pack_conn(ECPConnection *conn, unsigned char *packet, size_t pkt_size, unsigned char s_idx, unsigned char c_idx, unsigned char *payload, size_t pld_size, ECPNetAddr *addr, ECPSeqItem *si);
+ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr, ECPSeqItem *si);
 
 ssize_t ecp_unpack(ECPSocket *sock, ECPNetAddr *addr, ECPConnection *parent, ECP2Buffer *bufs, size_t pkt_size, ECPConnection **_conn, ecp_seq_t *_seq);
 ssize_t ecp_pkt_handle(ECPSocket *sock, ECPNetAddr *addr, ECPConnection *parent, ECP2Buffer *bufs, size_t pkt_size);
@@ -401,7 +394,8 @@ int ecp_pld_get_pts(unsigned char *payload, size_t pld_size, ecp_pts_t *pts);
 int ecp_pld_set_pts(unsigned char *payload, size_t pld_size, ecp_pts_t pts);
 unsigned char *ecp_pld_get_buf(unsigned char *payload, size_t pld_size);
 
-ssize_t _ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti);
+ssize_t __ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti, ECPSeqItem *si);
+ssize_t _ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti);
 ssize_t ecp_pld_send(ECPConnection *conn, ECPBuffer *packet, ECPBuffer *payload, size_t pld_size, unsigned char flags);
 ssize_t ecp_pld_send_wtimer(ECPConnection *conn, ECPBuffer *packet, ECPBuffer *payload, size_t pld_size, unsigned char flags, ECPTimerItem *ti);
 ssize_t ecp_pld_send_tr(ECPSocket *sock, ECPNetAddr *addr, ECPConnection *parent, ECPBuffer *packet, ECPPktMeta *pkt_meta, ECPBuffer *payload, size_t pld_size, unsigned char flags);
diff --git a/ecp/src/msgq.c b/ecp/src/msgq.c
index 61c7b02..8f81d8a 100644
--- a/ecp/src/msgq.c
+++ b/ecp/src/msgq.c
@@ -4,9 +4,6 @@
 
 #include <sys/time.h>
 
-#define MIN(a,b) (((a)<(b))?(a):(b))
-#define MAX(a,b) (((a)>(b))?(a):(b))
-
 #define MSG_IDX_MASK(idx)    ((idx) & ((ECP_MSGQ_MAX_MSG) - 1))
 
 static struct timespec *abstime_ts(struct timespec *ts, ecp_cts_t msec) {
@@ -25,8 +22,6 @@ int ecp_conn_msgq_create(ECPConnMsgQ *msgq) {
     int i;
     int rv;
 
-    if (msgq == NULL) return ECP_ERR;
-
     memset(msgq, 0, sizeof(ECPConnMsgQ));
 
     rv = pthread_mutex_init(&msgq->mutex, NULL);
@@ -51,8 +46,6 @@ int ecp_conn_msgq_create(ECPConnMsgQ *msgq) {
 void ecp_conn_msgq_destroy(ECPConnMsgQ *msgq) {
     int i;
 
-    if (msgq == NULL) return;
-
     for (i=0; i<ECP_MAX_MTYPE; i++) {
         pthread_cond_destroy(&msgq->cond[i]);
     }
@@ -60,8 +53,6 @@ void ecp_conn_msgq_destroy(ECPConnMsgQ *msgq) {
 }
 
 int ecp_conn_msgq_start(ECPConnMsgQ *msgq, ecp_seq_t seq) {
-    if (msgq == NULL) return ECP_ERR;
-
     msgq->seq_max = seq;
     msgq->seq_start = seq + 1;
 
@@ -70,13 +61,11 @@ int ecp_conn_msgq_start(ECPConnMsgQ *msgq, ecp_seq_t seq) {
 
 int ecp_conn_msgq_push(ECPConnection *conn, ecp_seq_t seq, unsigned char mtype) {
     ECPRBRecv *buf = conn->rbuf.recv;
-    ECPConnMsgQ *msgq = buf ? &buf->msgq : NULL;
+    ECPConnMsgQ *msgq = &buf->msgq;
 
-    mtype &= ECP_MTYPE_MASK;
-    if (msgq == NULL) return ECP_ERR;
     if (mtype >= ECP_MAX_MTYPE) return ECP_ERR_MAX_MTYPE;
 
-    if ((unsigned short)(msgq->idx_w[mtype] - msgq->idx_r[mtype]) == ECP_MSGQ_MAX_MSG) return ECP_MSGQ_ERR_MAX_MSG;
+    if ((unsigned short)(msgq->idx_w[mtype] - msgq->idx_r[mtype]) == ECP_MSGQ_MAX_MSG) return ECP_ERR_FULL;
     if (msgq->idx_w[mtype] == msgq->idx_r[mtype]) pthread_cond_signal(&msgq->cond[mtype]);
 
     msgq->seq_msg[mtype][MSG_IDX_MASK(msgq->idx_w[mtype])] = seq;
@@ -89,13 +78,15 @@ int ecp_conn_msgq_push(ECPConnection *conn, ecp_seq_t seq, unsigned char mtype)
 
 ssize_t ecp_conn_msgq_pop(ECPConnection *conn, unsigned char mtype, unsigned char *msg, size_t msg_size, ecp_cts_t timeout) {
     ECPRBRecv *buf = conn->rbuf.recv;
-    ECPConnMsgQ *msgq = buf ? &buf->msgq : NULL;
+    ECPConnMsgQ *msgq = &buf->msgq;
+    ECPRBuffer *rbuf = &buf->rbuf;
     ecp_seq_t seq;
-    ecp_seq_t seq_offset;
-    unsigned int idx;
+    unsigned char *msg_buf;
+    unsigned char *content;
+    unsigned short idx;
+    int _rv;
     ssize_t rv;
 
-    if (msgq == NULL) return ECP_ERR;
     if (mtype >= ECP_MAX_MTYPE) return ECP_ERR_MAX_MTYPE;
 
     if (msgq->idx_r[mtype] == msgq->idx_w[mtype]) {
@@ -103,35 +94,48 @@ ssize_t ecp_conn_msgq_pop(ECPConnection *conn, unsigned char mtype, unsigned cha
             pthread_cond_wait(&msgq->cond[mtype], &msgq->mutex);
         } else {
             struct timespec ts;
-            int _rv;
 
             _rv = pthread_cond_timedwait(&msgq->cond[mtype], &msgq->mutex, abstime_ts(&ts, timeout));
             if (_rv) return ECP_ERR_TIMEOUT;
         }
     }
-
     seq = msgq->seq_msg[mtype][MSG_IDX_MASK(msgq->idx_r[mtype])];
-    seq_offset = seq - buf->rbuf.seq_start;
-    idx = ECP_RBUF_IDX_MASK(buf->rbuf.msg_start + seq_offset, buf->rbuf.msg_size);
 
-    msgq->idx_r[mtype]++;
-    buf->rbuf.msg[idx].flags &= ~ECP_RBUF_FLAG_IN_MSGQ;
+    _rv = _ecp_rbuf_msg_idx(rbuf, seq, &idx);
+    if (_rv) return ECP_ERR;
 
+    msg_buf = rbuf->arr.msg[idx].buf;
+    rv = rbuf->arr.msg[idx].size;
+
+    content = ecp_msg_get_content(msg_buf, rv);
+    if (content == NULL) {
+        rv = ECP_ERR;
+        goto msgq_pop_fin;
+    }
+
+    rv -= content - msg_buf;
+    if (msg_size < rv) {
+        rv = ECP_ERR_FULL;
+        goto msgq_pop_fin;
+    }
+
+    memcpy(msg, content, rv);
+
+    rbuf->arr.msg[idx].flags &= ~ECP_RBUF_FLAG_IN_MSGQ;
+    // if (rbuf->arr.msg[idx].flags == 0);
+
+msgq_pop_fin:
+    msgq->idx_r[mtype]++;
     if (msgq->seq_start == seq) {
-        int i, _idx = idx;
-        ecp_seq_t msg_cnt = msgq->seq_max - msgq->seq_start + 1;
+        int i;
+        unsigned short msg_cnt = msgq->seq_max - msgq->seq_start + 1;
 
         for (i=0; i<msg_cnt; i++) {
-            if (buf->rbuf.msg[_idx].flags & ECP_RBUF_FLAG_IN_MSGQ) break;
-            _idx = ECP_RBUF_IDX_MASK(_idx + 1, buf->rbuf.msg_size);
+            if (rbuf->arr.msg[idx].flags & ECP_RBUF_FLAG_IN_MSGQ) break;
+            idx = ECP_RBUF_IDX_MASK(idx + 1, rbuf->arr_size);
         }
         msgq->seq_start += i;
     }
-    rv = buf->rbuf.msg[idx].size - 1;
-    if (rv >= 0) {
-        rv = MIN(msg_size, rv);
-        memcpy(msg, buf->rbuf.msg[idx].msg + 1, rv);
-    }
 
     return rv;
 }
diff --git a/ecp/src/msgq.h b/ecp/src/msgq.h
index a81ff36..394209f 100644
--- a/ecp/src/msgq.h
+++ b/ecp/src/msgq.h
@@ -1,7 +1,6 @@
 #ifdef ECP_WITH_MSGQ
 
 #define ECP_MSGQ_MAX_MSG        32
-#define ECP_MSGQ_ERR_MAX_MSG    -110
 
 typedef struct ECPConnMsgQ {
     unsigned short idx_w[ECP_MAX_MTYPE];
diff --git a/ecp/src/rbuf.c b/ecp/src/rbuf.c
index 9680d14..be8e9f3 100644
--- a/ecp/src/rbuf.c
+++ b/ecp/src/rbuf.c
@@ -1,18 +1,5 @@
 #include "core.h"
 
-int _ecp_rbuf_init(ECPRBuffer *rbuf, ECPRBMessage *msg, unsigned int msg_size) {
-    rbuf->msg = msg;
-    if (msg_size) {
-        if (msg == NULL) return ECP_ERR;
-        rbuf->msg_size = msg_size;
-        memset(rbuf->msg, 0, sizeof(ECPRBMessage) * msg_size);
-    } else {
-        rbuf->msg_size = ECP_SEQ_HALF;
-    }
-
-    return ECP_OK;
-}
-
 int _ecp_rbuf_start(ECPRBuffer *rbuf, ecp_seq_t seq) {
     rbuf->seq_max = seq;
     rbuf->seq_start = seq + 1;
@@ -20,29 +7,17 @@ int _ecp_rbuf_start(ECPRBuffer *rbuf, ecp_seq_t seq) {
     return ECP_OK;
 }
 
-int _ecp_rbuf_msg_idx(ECPRBuffer *rbuf, ecp_seq_t seq) {
+int _ecp_rbuf_msg_idx(ECPRBuffer *rbuf, ecp_seq_t seq, unsigned short *idx) {
     ecp_seq_t seq_offset = seq - rbuf->seq_start;
 
-    // This also checks for seq_start <= seq if seq type range >> rbuf->msg_size
-    if (seq_offset < rbuf->msg_size) return ECP_RBUF_IDX_MASK(rbuf->msg_start + seq_offset, rbuf->msg_size);
-    return ECP_ERR_RBUF_FULL;
-}
+    /* This also checks for seq_start <= seq if seq type range >> rbuf->arr_size */
+    if (seq_offset >= rbuf->arr_size) return ECP_ERR_FULL;
 
-ssize_t _ecp_rbuf_msg_store(ECPRBuffer *rbuf, ecp_seq_t seq, int idx, unsigned char *msg, size_t msg_size, unsigned char test_flags, unsigned char set_flags) {
-    idx = idx < 0 ? _ecp_rbuf_msg_idx(rbuf, seq) : idx;
-    if (idx < 0) return idx;
-
-    if (rbuf->msg == NULL) return 0;
-    if (test_flags && (test_flags & rbuf->msg[idx].flags)) return ECP_ERR_RBUF_DUP;
-
-    if (msg_size) memcpy(rbuf->msg[idx].msg, msg, msg_size);
-    rbuf->msg[idx].size = msg_size;
-    rbuf->msg[idx].flags = set_flags;
-
-    return msg_size;
+    *idx = ECP_RBUF_IDX_MASK(rbuf->idx_start + seq_offset, rbuf->arr_size);
+    return ECP_OK;
 }
 
-int ecp_rbuf_create(ECPConnection *conn, ECPRBSend *buf_s, ECPRBMessage *msg_s, unsigned int msg_s_size, ECPRBRecv *buf_r, ECPRBMessage *msg_r, unsigned int msg_r_size) {
+int ecp_rbuf_create(ECPConnection *conn, ECPRBSend *buf_s, ECPRBPacket *msg_s, unsigned int msg_s_size, ECPRBRecv *buf_r, ECPRBMessage *msg_r, unsigned int msg_r_size) {
     int rv;
 
     if (buf_s) {
@@ -72,39 +47,16 @@ void ecp_rbuf_destroy(ECPConnection *conn) {
     ecp_rbuf_recv_destroy(conn);
 }
 
-ssize_t ecp_rbuf_pld_send(ECPConnection *conn, ECPBuffer *packet, ECPBuffer *payload, size_t pld_size, unsigned char flags, ecp_seq_t seq) {
-    ECPSocket *sock = conn->sock;
-    ECPContext *ctx = sock->ctx;
-    ECPNetAddr addr;
-    ECPSeqItem seq_item;
-    ssize_t rv;
-    int _rv;
-
-    _rv = ecp_seq_item_init(&seq_item);
-    if (_rv) return _rv;
-
-    seq_item.seq = seq;
-    seq_item.seq_w = 1;
-    seq_item.rb_pass = 1;
-
-    rv = ecp_pack_conn(conn, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, &seq_item, payload, pld_size, &addr);
-    if (rv < 0) return rv;
-
-    rv = ecp_pkt_send(sock, &addr, packet, rv, flags);
-    if (rv < 0) return rv;
-
-    return rv;
-}
-
 int ecp_rbuf_handle_seq(ECPConnection *conn, unsigned char mtype) {
     if (conn->rbuf.recv || (mtype == ECP_MTYPE_RBACK) || (mtype == ECP_MTYPE_RBFLUSH)) return 1;
     return 0;
 }
 
 int ecp_rbuf_set_seq(ECPConnection *conn, ECPSeqItem *si, unsigned char *payload, size_t pld_size) {
-    ECPRBSend *buf;
+    ECPRBSend *buf = conn->rbuf.send;
+    ECPRBuffer *rbuf = &buf->rbuf;
     unsigned char mtype;
-    int idx;
+    unsigned short idx;
     int rv;
 
     if (si->rb_pass) return ECP_OK;
@@ -113,86 +65,142 @@ int ecp_rbuf_set_seq(ECPConnection *conn, ECPSeqItem *si, unsigned char *payload
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_lock(&buf->mutex);
 #endif
-    idx = _ecp_rbuf_msg_idx(&buf->rbuf, si->seq);
+    rv = _ecp_rbuf_msg_idx(rbuf, si->seq, &idx);
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_unlock(&buf->mutex);
 #endif
-
-    if (idx < 0) return idx;
+    if (rv) return rv;
 
     rv = ecp_pld_get_type(payload, pld_size, &mtype);
     if (rv) return rv;
 
     si->rb_mtype = mtype;
     si->rb_idx = idx;
-    buf->rbuf.msg[idx].size = 0;
-    buf->rbuf.msg[idx].flags = 0;
+    rbuf->arr.pkt[idx].size = 0;
+    rbuf->arr.pkt[idx].flags = 0;
 
     return ECP_OK;
 }
 
+ssize_t ecp_rbuf_pld_send(ECPConnection *conn, ECPBuffer *packet, ECPBuffer *payload, size_t pld_size, unsigned char flags, ecp_seq_t seq) {
+    ECPSocket *sock = conn->sock;
+    ECPContext *ctx = sock->ctx;
+    ECPNetAddr addr;
+    ECPSeqItem seq_item;
+    int _rv;
+    ssize_t rv;
+
+    _rv = ecp_seq_item_init(&seq_item);
+    if (_rv) return _rv;
+
+    seq_item.seq = seq;
+    seq_item.seq_w = 1;
+    seq_item.rb_pass = 1;
+
+    rv = ecp_pack_conn(conn, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, payload, pld_size, &addr, &seq_item);
+    if (rv < 0) return rv;
+
+    rv = ecp_pkt_send(sock, &addr, packet, rv, flags);
+    if (rv < 0) return rv;
+
+    return rv;
+}
+
 ssize_t ecp_rbuf_pkt_send(ECPConnection *conn, ECPSocket *sock, ECPNetAddr *addr, ECPBuffer *packet, size_t pkt_size, unsigned char flags, ECPTimerItem *ti, ECPSeqItem *si) {
-    ECPRBSend *buf;
-    int do_send = 1;
+    ECPRBSend *buf = conn->rbuf.send;
+    ECPRBuffer *rbuf = &buf->rbuf;
+    ecp_seq_t seq = si->seq;
+    unsigned short idx = si->rb_idx;
+    unsigned char mtype = si->rb_mtype & ECP_MTYPE_MASK;
+    unsigned char _flags;
+    int rb_rel;
+    int rb_cc;
+    int do_send;
+    int do_skip;
+    int _rv = ECP_OK;
     ssize_t rv = 0;
 
-    buf = conn->rbuf.send;
-    if (!si->rb_pass) {
-        unsigned char flags = 0;
-        ecp_seq_t seq = si->seq;
-        unsigned int idx = si->rb_idx;
-        unsigned char mtype = si->rb_mtype & ECP_MTYPE_MASK;
+    if (pkt_size == 0) return ECP_ERR;
+
+    do_send = 1;
+    do_skip = ecp_rbuf_skip(mtype);
+
+#ifdef ECP_WITH_PTHREAD
+    pthread_mutex_lock(&buf->mutex);
+#endif
+
+    rb_rel = (buf->flags & ECP_RBUF_FLAG_RELIABLE);
+    rb_cc = ((buf->flags & ECP_RBUF_FLAG_CCONTROL) && (buf->cnt_cc || (buf->in_transit >= buf->win_size)));
+
+    if (rb_rel || rb_cc) {
+        ECPRBTimer *rb_timer = NULL;
+        ECPRBTimerItem *rb_ti = NULL;
 
-        if (mtype < ECP_MAX_MTYPE_SYS) flags |= ECP_RBUF_FLAG_SYS;
+        _flags = ECP_RBUF_FLAG_IN_RBUF;
+        if (do_skip) {
+            _flags |= ECP_RBUF_FLAG_SKIP;
+        } else {
+            do_send = 0;
+        }
 
-        rv = _ecp_rbuf_msg_store(&buf->rbuf, seq, idx, packet->buffer, pkt_size, 0, flags);
-        if (rv < 0) return rv;
+        if (rbuf->arr.pkt[idx].flags) _rv = ECP_ERR_RBUF_DUP;
 
-        if (buf->flags & ECP_RBUF_FLAG_CCONTROL) {
-            int _rv = ECP_OK;
+        if (!_rv && !do_send && ti) {
+            rb_timer = buf->timer;
 
 #ifdef ECP_WITH_PTHREAD
-            pthread_mutex_lock(&buf->mutex);
+            pthread_mutex_lock(&rb_timer->mutex);
 #endif
 
-            if (ECP_SEQ_LT(buf->rbuf.seq_max, seq)) buf->rbuf.seq_max = seq;
-
-            if (buf->cnt_cc || (buf->in_transit >= buf->win_size)) {
-                if (!buf->cnt_cc) buf->seq_cc = seq;
-                buf->cnt_cc++;
-                buf->rbuf.msg[idx].flags |= ECP_RBUF_FLAG_IN_CCONTROL;
-                do_send = 0;
-                if (ti) {
-                    ECPRBTimer *timer = &buf->timer;
-                    ECPRBTimerItem *item = &timer->item[timer->idx_w];
-
-                    if (!item->occupied) {
-                        item->occupied = 1;
-                        item->item = *ti;
-                        buf->rbuf.msg[idx].idx_t = timer->idx_w;
-                        timer->idx_w = (timer->idx_w) % ECP_MAX_TIMER;
-                    } else {
-                        _rv = ECP_ERR_MAX_TIMER;
-                    }
-                } else {
-                    buf->rbuf.msg[idx].idx_t = -1;
-                }
+            rb_ti = &rb_timer->item[rb_timer->idx_w];
+            if (rb_ti->empty) {
+                rb_ti->empty = 0;
+                rb_ti->item = *ti;
+                rb_timer->idx_w = (rb_timer->idx_w + 1) % ECP_MAX_TIMER;
             } else {
-                buf->in_transit++;
+                _rv = ECP_ERR_MAX_TIMER;
             }
 
 #ifdef ECP_WITH_PTHREAD
-            pthread_mutex_unlock(&buf->mutex);
+            pthread_mutex_unlock(&rb_timer->mutex);
 #endif
+        }
 
-            if (_rv) return _rv;
+        if (_rv) {
+            rv = _rv;
+            goto pkt_send_fin;
+        }
+
+        if (!do_send) {
+            memcpy(rbuf->arr.pkt[idx].buf, packet->buffer, pkt_size);
+            rbuf->arr.pkt[idx].size = pkt_size;
+            rbuf->arr.pkt[idx].timer = rb_ti;
+            rv = pkt_size;
+        }
+        rbuf->arr.pkt[idx].flags = _flags;
+
+        if (ECP_SEQ_LT(rbuf->seq_max, seq)) rbuf->seq_max = seq;
+
+        if (rb_cc && !do_send) {
+            if (buf->cnt_cc == 0) buf->seq_cc = seq;
+            buf->cnt_cc++;
         }
     }
 
+    if ((buf->flags & ECP_RBUF_FLAG_CCONTROL) && !do_skip && do_send) {
+        buf->in_transit++;
+    }
+
+pkt_send_fin:
+
+#ifdef ECP_WITH_PTHREAD
+    pthread_mutex_unlock(&buf->mutex);
+#endif
+
+    if (rv < 0) return rv;
+
     if (do_send) {
         if (ti) {
-            int _rv;
-
             _rv = ecp_timer_push(ti);
             if (_rv) return _rv;
         }
diff --git a/ecp/src/rbuf.h b/ecp/src/rbuf.h
index 891f29d..31aeb39 100644
--- a/ecp/src/rbuf.h
+++ b/ecp/src/rbuf.h
@@ -1,7 +1,7 @@
 #define ECP_RBUF_FLAG_IN_RBUF       0x01
 #define ECP_RBUF_FLAG_IN_MSGQ       0x02
-#define ECP_RBUF_FLAG_IN_CCONTROL   0x04
-#define ECP_RBUF_FLAG_SYS           0x80
+#define ECP_RBUF_FLAG_IN_TIMER      0x04
+#define ECP_RBUF_FLAG_SKIP          0x08
 
 #define ECP_RBUF_FLAG_CCONTROL      0x01
 #define ECP_RBUF_FLAG_RELIABLE      0x02
@@ -9,58 +9,66 @@
 
 #define ECP_MTYPE_RBACK             0x04
 #define ECP_MTYPE_RBFLUSH           0x05
-#define ECP_MTYPE_RBFLUSH_PTS       0x06
+#define ECP_MTYPE_RBTIMER           0x06
 #define ECP_MTYPE_NOP               0x07
 
 #define ECP_ERR_RBUF_DUP            -100
-#define ECP_ERR_RBUF_FULL           -101
 
 typedef uint32_t ecp_win_t;
 
 /* size must be power of 2 */
 #define ECP_RBUF_IDX_MASK(idx, size)    ((idx) & ((size) - 1))
+#define ecp_rbuf_skip(mtype)            ((mtype & ECP_MTYPE_MASK) < ECP_MTYPE_NOP ? 1 : 0)
 
 #ifdef ECP_WITH_MSGQ
 #include "msgq.h"
 #endif
 
 typedef struct ECPRBTimerItem {
-    unsigned char occupied;
     ECPTimerItem item;
+    unsigned char empty;
 } ECPRBTimerItem;
 
 typedef struct ECPRBTimer {
     ECPRBTimerItem item[ECP_MAX_TIMER];
     unsigned short idx_w;
+#ifdef ECP_WITH_PTHREAD
+    pthread_mutex_t mutex;
+#endif
 } ECPRBTimer;
 
 typedef struct ECPRBMessage {
-    unsigned char msg[ECP_MAX_PKT];
-    ssize_t size;
+    unsigned char buf[ECP_MAX_MSG];
+    size_t size;
     unsigned char flags;
-    short idx_t;
 } ECPRBMessage;
 
+typedef struct ECPRBPacket {
+    unsigned char buf[ECP_MAX_PKT];
+    size_t size;
+    unsigned char flags;
+    ECPRBTimerItem *timer;
+} ECPRBPacket;
+
 typedef struct ECPRBuffer {
     ecp_seq_t seq_start;
     ecp_seq_t seq_max;
-    unsigned int msg_size;
-    unsigned int msg_start;
-    ECPRBMessage *msg;
+    unsigned short arr_size;
+    unsigned short idx_start;
+    union {
+        ECPRBMessage *msg;
+        ECPRBPacket *pkt;
+    } arr;
 } ECPRBuffer;
 
 typedef struct ECPRBRecv {
     unsigned char flags;
-    unsigned char timer_pts;
-    unsigned char ack_do;
+    ecp_cts_t deliver_delay;
     unsigned short hole_max;
     unsigned short ack_rate;
-    ecp_pts_t deliver_delay;
+    unsigned short ack_pkt;
     ecp_seq_t seq_ack;
-    ecp_seq_t ack_pkt;
     ecp_ack_t ack_map;
-    ecp_ack_t hole_mask_full;
-    ecp_ack_t hole_mask_empty;
     ECPRBuffer rbuf;
 #ifdef ECP_WITH_MSGQ
     ECPConnMsgQ msgq;
@@ -70,15 +78,16 @@ typedef struct ECPRBRecv {
 
 typedef struct ECPRBSend {
     unsigned char flags;
-    unsigned char flush;
     ecp_win_t win_size;
     ecp_win_t in_transit;
     ecp_win_t cnt_cc;
     ecp_seq_t seq_cc;
     ecp_seq_t seq_flush;
+    ecp_seq_t seq_nack;
+    unsigned char flush;
     unsigned int nack_rate;
     ECPRBuffer rbuf;
-    ECPRBTimer timer;
+    ECPRBTimer *timer;
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_t mutex;
 #endif
@@ -89,28 +98,26 @@ typedef struct ECPConnRBuffer {
     ECPRBSend *send;
 } ECPConnRBuffer;
 
-int _ecp_rbuf_init(ECPRBuffer *rbuf, ECPRBMessage *msg, unsigned int msg_size);
 int _ecp_rbuf_start(ECPRBuffer *rbuf, ecp_seq_t seq);
-int _ecp_rbuf_msg_idx(ECPRBuffer *rbuf, ecp_seq_t seq);
-ssize_t _ecp_rbuf_msg_store(ECPRBuffer *rbuf, ecp_seq_t seq, int idx, unsigned char *msg, size_t msg_size, unsigned char test_flags, unsigned char set_flags);
+int _ecp_rbuf_msg_idx(ECPRBuffer *rbuf, ecp_seq_t seq, unsigned short *idx);
 
-int ecp_rbuf_create(struct ECPConnection *conn, ECPRBSend *buf_s, ECPRBMessage *msg_s, unsigned int msg_s_size, ECPRBRecv *buf_r, ECPRBMessage *msg_r, unsigned int msg_r_size);
+int ecp_rbuf_create(struct ECPConnection *conn, ECPRBSend *buf_s, ECPRBPacket *msg_s, unsigned int msg_s_size, ECPRBRecv *buf_r, ECPRBMessage *msg_r, unsigned int msg_r_size);
 void ecp_rbuf_destroy(struct ECPConnection *conn);
 ssize_t ecp_rbuf_pld_send(struct ECPConnection *conn, struct ECPBuffer *packet, struct ECPBuffer *payload, size_t pld_size, unsigned char flags, ecp_seq_t seq);
 int ecp_rbuf_handle_seq(struct ECPConnection *conn, unsigned char mtype);
 int ecp_rbuf_set_seq(struct ECPConnection *conn, struct ECPSeqItem *si, unsigned char *payload, size_t pld_size);
 ssize_t ecp_rbuf_pkt_send(struct ECPConnection *conn, struct ECPSocket *sock, ECPNetAddr *addr, struct ECPBuffer *packet, size_t pkt_size, unsigned char flags, ECPTimerItem *ti, struct ECPSeqItem *si);
 
-int ecp_rbuf_recv_create(struct ECPConnection *conn, ECPRBRecv *buf, ECPRBMessage *msg, unsigned int msg_size);
+int ecp_rbuf_recv_create(struct ECPConnection *conn, ECPRBRecv *buf, ECPRBMessage *msg, unsigned short msg_size);
 void ecp_rbuf_recv_destroy(struct ECPConnection *conn);
 int ecp_rbuf_recv_start(struct ECPConnection *conn, ecp_seq_t seq);
 int ecp_rbuf_set_hole(struct ECPConnection *conn, unsigned short hole_max);
-int ecp_rbuf_set_delay(struct ECPConnection *conn, ecp_pts_t delay);
+int ecp_rbuf_set_delay(struct ECPConnection *conn, ecp_cts_t delay);
 
 ssize_t ecp_rbuf_store(struct ECPConnection *conn, ecp_seq_t seq, unsigned char *msg, size_t msg_size, struct ECP2Buffer *b);
 struct ECPFragIter *ecp_rbuf_get_frag_iter(struct ECPConnection *conn);
 
-int ecp_rbuf_send_create(struct ECPConnection *conn, ECPRBSend *buf, ECPRBMessage *msg, unsigned int msg_size);
+int ecp_rbuf_send_create(struct ECPConnection *conn, ECPRBSend *buf, ECPRBPacket *msg, unsigned short msg_size);
 void ecp_rbuf_send_destroy(struct ECPConnection *conn);
 int ecp_rbuf_send_start(struct ECPConnection *conn);
 int ecp_rbuf_flush(struct ECPConnection *conn);
@@ -118,4 +125,4 @@ int ecp_rbuf_set_wsize(struct ECPConnection *conn, ecp_win_t size);
 
 ssize_t ecp_rbuf_handle_ack(struct ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, struct ECP2Buffer *b);
 ssize_t ecp_rbuf_handle_flush(struct ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, struct ECP2Buffer *b);
-ssize_t ecp_rbuf_handle_flush_pts(struct ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, struct ECP2Buffer *b);
+ssize_t ecp_rbuf_handle_timer(struct ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, struct ECP2Buffer *b);
diff --git a/ecp/src/rbuf_recv.c b/ecp/src/rbuf_recv.c
index f2bb1c2..98b472c 100644
--- a/ecp/src/rbuf_recv.c
+++ b/ecp/src/rbuf_recv.c
@@ -5,130 +5,115 @@
 #define ACK_RATE            8
 #define ACK_MASK_FIRST      ((ecp_ack_t)1 << (ECP_SIZE_ACKB - 1))
 
-static ssize_t msg_store(ECPConnection *conn, ecp_seq_t seq, unsigned char *msg, size_t msg_size, ECP2Buffer *b) {
+static ssize_t msg_store(ECPConnection *conn, ecp_seq_t seq, unsigned char *msg, size_t msg_size, unsigned char mtype) {
     ECPRBRecv *buf = conn->rbuf.recv;
-    unsigned char flags = ECP_RBUF_FLAG_IN_RBUF;
-    unsigned char mtype;
-    ssize_t rv;
-    int _rv;
+    ECPRBuffer *rbuf = &buf->rbuf;
+    unsigned short idx;
+    unsigned char flags;
+    int skip;
+    int rv;
 
-    _rv = ecp_msg_get_type(msg, msg_size, &mtype);
-    if (_rv) return _rv;
+    rv = _ecp_rbuf_msg_idx(rbuf, seq, &idx);
+    if (rv) return rv;
 
-    mtype &= ECP_MTYPE_MASK;
-    if (mtype < ECP_MAX_MTYPE_SYS) flags |= ECP_RBUF_FLAG_SYS;
+    if (rbuf->arr.msg[idx].flags) return ECP_ERR_RBUF_DUP;
 
 #ifdef ECP_WITH_MSGQ
     if (buf->flags & ECP_RBUF_FLAG_MSGQ) {
         ecp_seq_t seq_offset;
-        int _rv = ECP_OK;
 
         pthread_mutex_lock(&buf->msgq.mutex);
+
         seq_offset = seq - buf->msgq.seq_start;
-        if (seq_offset >= buf->rbuf.msg_size) _rv = ECP_ERR_RBUF_FULL;
+        if (seq_offset >= rbuf->arr_size) rv = ECP_ERR_FULL;
+
         pthread_mutex_unlock(&buf->msgq.mutex);
 
-        if (_rv) return _rv;
+        if (rv) return rv;
     }
 #endif
 
-    rv = _ecp_rbuf_msg_store(&buf->rbuf, seq, -1, msg, msg_size, ECP_RBUF_FLAG_IN_RBUF | ECP_RBUF_FLAG_IN_MSGQ, flags);
-    if (rv < 0) return rv;
+    skip = ecp_rbuf_skip(mtype);
+    flags = ECP_RBUF_FLAG_IN_RBUF;
+    if (skip) flags |= ECP_RBUF_FLAG_SKIP;
+    rbuf->arr.msg[idx].flags = flags;
 
-    if (ECP_SEQ_LT(buf->rbuf.seq_max, seq)) buf->rbuf.seq_max = seq;
-    if (flags & ECP_RBUF_FLAG_SYS) ecp_conn_handle_msg(conn, seq, msg, msg_size, b);
+    if (skip) return 0;
 
-    return rv;
+    memcpy(rbuf->arr.msg[idx].buf, msg, msg_size);
+    rbuf->arr.msg[idx].size = msg_size;
+    if (ECP_SEQ_LT(rbuf->seq_max, seq)) rbuf->seq_max = seq;
+
+    return msg_size;
 }
 
 static void msg_flush(ECPConnection *conn, ECP2Buffer *b) {
     ECPRBRecv *buf = conn->rbuf.recv;
+    ECPRBuffer *rbuf = &buf->rbuf;
+    ecp_seq_t seq;
+    unsigned short idx;
+    int i;
 
 #ifdef ECP_WITH_MSGQ
     if (buf->flags & ECP_RBUF_FLAG_MSGQ) pthread_mutex_lock(&buf->msgq.mutex);
 #endif
 
-    ecp_seq_t msg_cnt = buf->rbuf.seq_max - buf->rbuf.seq_start + 1;
-    ecp_seq_t seq_next = buf->rbuf.seq_start;
-    ecp_seq_t i = 0;
-    unsigned int idx = buf->rbuf.msg_start;
+    seq = rbuf->seq_start;
+    idx = rbuf->idx_start;
 
-    if (buf->timer_pts) {
-        ecp_timer_pop(conn, ECP_MTYPE_RBFLUSH_PTS);
-        buf->timer_pts = 0;
-    }
+    unsigned short msg_cnt = rbuf->seq_max - rbuf->seq_start + 1;
 
-    for (i=0; i<msg_cnt; i++) {
-        if (buf->rbuf.msg[idx].flags & ECP_RBUF_FLAG_IN_RBUF) {
-            if (buf->rbuf.msg[idx].flags & ECP_RBUF_FLAG_SYS) {
-                buf->rbuf.msg[idx].flags &= ~ECP_RBUF_FLAG_SYS;
-            } else {
+    while (ECP_SEQ_LTE(seq, rbuf->seq_max)) {
+        if (rbuf->arr.msg[idx].flags & ECP_RBUF_FLAG_IN_RBUF) {
+            if (!(rbuf->arr.msg[idx].flags & ECP_RBUF_FLAG_SKIP)) {
                 ecp_pts_t msg_pts;
-                ecp_seq_t seq = buf->rbuf.seq_start + i;
-                unsigned char frag_tot;
-                unsigned char frag_cnt;
-                uint16_t frag_size;
                 int rv;
 
-                rv = ecp_msg_get_frag(buf->rbuf.msg[idx].msg, buf->rbuf.msg[idx].size, &frag_cnt, &frag_tot, &frag_size);
-                if (!rv && (frag_cnt != 0) && (seq != seq_next)) {
-                    ecp_seq_t seq_fend = seq + (ecp_seq_t)(frag_tot - frag_cnt - 1);
-
-                    if (ECP_SEQ_LT(buf->rbuf.seq_max, seq_fend) || (buf->hole_max && ((ecp_seq_t)(buf->rbuf.seq_max - seq_fend) <= buf->hole_max))) {
-                        ecp_seq_t seq_fbeg = seq - frag_cnt;
-                        ecp_seq_t seq_offset = ECP_SEQ_LT(seq_next, seq_fbeg) ? seq - seq_fbeg : seq - seq_next;
-
-                        i -= seq_offset;
-                        idx = ECP_RBUF_IDX_MASK(idx - seq_offset, buf->rbuf.msg_size);
-                        break;
-                    }
-                }
+                rv = ecp_msg_get_pts(rbuf->arr.msg[idx].buf, rbuf->arr.msg[idx].size, &msg_pts);
+                if (!rv && buf->deliver_delay) {
+                    ecp_cts_t now = ecp_tm_abstime_ms(0);
 
-                rv = ecp_msg_get_pts(buf->rbuf.msg[idx].msg, buf->rbuf.msg[idx].size, &msg_pts);
-                if (!rv) {
-                    ecp_pts_t now = ecp_tm_abstime_ms(0);
+                    msg_pts += buf->deliver_delay;
                     if (ECP_PTS_LT(now, msg_pts)) {
-                        ECPTimerItem ti;
-                        ecp_seq_t seq_offset = seq - seq_next;
+                        if (!(rbuf->arr.msg[idx].flags & ECP_RBUF_FLAG_IN_TIMER)) {
+                            ECPTimerItem ti;
 
-                        rv = ecp_timer_item_init(&ti, conn, ECP_MTYPE_RBFLUSH_PTS, 0, msg_pts - now);
-                        if (!rv) rv = ecp_timer_push(&ti);
-                        if (!rv) buf->timer_pts = 1;
-
-                        i -= seq_offset;
-                        idx = ECP_RBUF_IDX_MASK(idx - seq_offset, buf->rbuf.msg_size);
+                            rv = ecp_timer_item_init(&ti, conn, ECP_MTYPE_RBTIMER, 0, msg_pts - now);
+                            if (!rv) rv = ecp_timer_push(&ti);
+                            if (!rv) rbuf->arr.msg[idx].flags |= ECP_RBUF_FLAG_IN_TIMER;
+                        }
                         break;
+                    } else if (rbuf->arr.msg[idx].flags & ECP_RBUF_FLAG_IN_TIMER) {
+                        rbuf->arr.msg[idx].flags &= ~ECP_RBUF_FLAG_IN_TIMER;
                     }
                 }
 
-                seq_next = seq + 1;
 #ifdef ECP_WITH_MSGQ
                 if (buf->flags & ECP_RBUF_FLAG_MSGQ) {
                     unsigned char mtype;
 
-                    rv = ecp_msg_get_type(buf->rbuf.msg[idx].msg, buf->rbuf.msg[idx].size, &mtype);
-                    if (!rv) rv = ecp_conn_msgq_push(conn, seq, mtype);
+                    rv = ecp_msg_get_type(rbuf->arr.msg[idx].buf, rbuf->arr.msg[idx].size, &mtype);
+                    if (!rv) rv = ecp_conn_msgq_push(conn, seq, mtype & ECP_MTYPE_MASK);
                     if (rv) break;
 
-                    buf->rbuf.msg[idx].flags |= ECP_RBUF_FLAG_IN_MSGQ;
+                    rbuf->arr.msg[idx].flags |= ECP_RBUF_FLAG_IN_MSGQ;
                 } else
-
 #endif
-                    ecp_conn_handle_msg(conn, seq, buf->rbuf.msg[idx].msg, buf->rbuf.msg[idx].size, b);
+                    ecp_conn_handle_msg(conn, seq, rbuf->arr.msg[idx].buf, rbuf->arr.msg[idx].size, b);
+            } else {
+                rbuf->arr.msg[idx].flags &= ~ECP_RBUF_FLAG_SKIP;
             }
-            buf->rbuf.msg[idx].flags &= ~ECP_RBUF_FLAG_IN_RBUF;
+            rbuf->arr.msg[idx].flags &= ~ECP_RBUF_FLAG_IN_RBUF;
+            // if (rbuf->arr.msg[idx].flags == 0);
         } else {
             if (buf->flags & ECP_RBUF_FLAG_RELIABLE) break;
-            if (buf->hole_max) {
-                ecp_seq_t seq = buf->rbuf.seq_start + i;
-                ecp_seq_t seq_offset = buf->rbuf.seq_max - seq;
-                if (seq_offset <= buf->hole_max) break;
-            }
+            if (!ECP_SEQ_LT(seq, rbuf->seq_max - buf->hole_max)) break;
         }
-        idx = ECP_RBUF_IDX_MASK(idx + 1, buf->rbuf.msg_size);
+        seq++;
+        idx = ECP_RBUF_IDX_MASK(idx + 1, rbuf->arr_size);
     }
-    buf->rbuf.seq_start += i;
-    buf->rbuf.msg_start = idx;
+    rbuf->seq_start = seq;
+    rbuf->idx_start = idx;
 
 #ifdef ECP_WITH_MSGQ
     if (buf->flags & ECP_RBUF_FLAG_MSGQ) pthread_mutex_unlock(&buf->msgq.mutex);
@@ -136,7 +121,7 @@ static void msg_flush(ECPConnection *conn, ECP2Buffer *b) {
 
 }
 
-static int ack_send(ECPConnection *conn) {
+static int ack_send(ECPConnection *conn, ecp_seq_t seq_ack, ecp_seq_t ack_map) {
     ECPRBRecv *buf = conn->rbuf.recv;
     ECPBuffer packet;
     ECPBuffer payload;
@@ -152,56 +137,53 @@ static int ack_send(ECPConnection *conn) {
 
     ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_RBACK);
     _buf = ecp_pld_get_buf(payload.buffer, payload.size);
-    _buf[0] = (buf->seq_ack & 0xFF000000) >> 24;
-    _buf[1] = (buf->seq_ack & 0x00FF0000) >> 16;
-    _buf[2] = (buf->seq_ack & 0x0000FF00) >> 8;
-    _buf[3] = (buf->seq_ack & 0x000000FF);
-    _buf[4] = (buf->ack_map & 0xFF000000) >> 24;
-    _buf[5] = (buf->ack_map & 0x00FF0000) >> 16;
-    _buf[6] = (buf->ack_map & 0x0000FF00) >> 8;
-    _buf[7] = (buf->ack_map & 0x000000FF);
-
-    rv = ecp_rbuf_pld_send(conn, &packet, &payload, ECP_SIZE_PLD(sizeof(ecp_seq_t) + sizeof(ecp_ack_t), ECP_MTYPE_RBACK), 0, 0);
+    _buf[0] = (seq_ack & 0xFF000000) >> 24;
+    _buf[1] = (seq_ack & 0x00FF0000) >> 16;
+    _buf[2] = (seq_ack & 0x0000FF00) >> 8;
+    _buf[3] = (seq_ack & 0x000000FF);
+    _buf[4] = (ack_map & 0xFF000000) >> 24;
+    _buf[5] = (ack_map & 0x00FF0000) >> 16;
+    _buf[6] = (ack_map & 0x0000FF00) >> 8;
+    _buf[7] = (ack_map & 0x000000FF);
+
+    rv = ecp_pld_send(conn, &packet, &payload, ECP_SIZE_PLD(sizeof(ecp_seq_t) + sizeof(ecp_ack_t), ECP_MTYPE_RBACK), 0);
     if (rv < 0) return rv;
 
     buf->ack_pkt = 0;
-    buf->ack_do = 0;
+
     return ECP_OK;
 }
 
 static int ack_shift(ECPRBRecv *buf) {
+    ECPRBuffer *rbuf = &buf->rbuf;
+    unsigned short idx;
     int do_ack = 0;
     int in_rbuf = 0;
-    int idx;
-    int i;
+    int rv;
 
     if ((buf->flags & ECP_RBUF_FLAG_RELIABLE) && ((buf->ack_map & ACK_MASK_FIRST) == 0)) return 0;
 
-    while (ECP_SEQ_LT(buf->seq_ack, buf->rbuf.seq_max)) {
+    /* walks through messages that are not delivered yet, so no need for msgq mutex lock */
+    while (ECP_SEQ_LT(buf->seq_ack, rbuf->seq_max)) {
         buf->seq_ack++;
-        in_rbuf = ECP_SEQ_LT(buf->seq_ack, buf->rbuf.seq_start) ? 1 : buf->rbuf.msg[ECP_RBUF_IDX_MASK(buf->rbuf.msg_start + buf->seq_ack - buf->rbuf.seq_start, buf->rbuf.msg_size)].flags & ECP_RBUF_FLAG_IN_RBUF;
-
+        rv = _ecp_rbuf_msg_idx(rbuf, buf->seq_ack, &idx);
+        if (!rv) {
+            in_rbuf = rbuf->arr.msg[idx].flags & ECP_RBUF_FLAG_IN_RBUF;
+        } else {
+            in_rbuf = 1;
+        }
         if (in_rbuf && (buf->ack_map == ECP_ACK_FULL)) continue;
 
         buf->ack_map = buf->ack_map << 1;
         if (in_rbuf) {
             buf->ack_map |= 1;
-        } else if (!do_ack && ECP_SEQ_LTE(buf->seq_ack, buf->rbuf.seq_max - 2 * buf->hole_max)) {
+        } else if (!do_ack && ECP_SEQ_LT(buf->seq_ack, rbuf->seq_max - buf->hole_max)) {
             do_ack = 1;
         }
 
-        if ((buf->ack_map & ACK_MASK_FIRST) == 0) break;
-    }
-
-    if (!do_ack && (buf->seq_ack == buf->rbuf.seq_max) && ((buf->ack_map & buf->hole_mask_full) != buf->hole_mask_full)) {
-        ecp_ack_t hole_mask = buf->ack_map;
-
-        for (i=0; i<buf->hole_max-1; i++) {
-            hole_mask = hole_mask >> 1;
-            if ((hole_mask & buf->hole_mask_empty) == 0) {
-                do_ack = 1;
-                break;
-            }
+        if ((buf->flags & ECP_RBUF_FLAG_RELIABLE) && ((buf->ack_map & ACK_MASK_FIRST) == 0)) {
+            do_ack = 1;
+            break;
         }
     }
 
@@ -209,34 +191,38 @@ static int ack_shift(ECPRBRecv *buf) {
 }
 
 ssize_t ecp_rbuf_handle_flush(ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, ECP2Buffer *b) {
-    if (size < 0) return size;
-
     ECPRBRecv *buf = conn->rbuf.recv;
+
     if (buf == NULL) return ECP_ERR;
+    if (size < 0) return size;
 
     ecp_tr_release(b->packet, 1);
-    ack_send(conn);
+    ack_send(conn, buf->seq_ack, buf->ack_map);
     return 0;
 }
 
-ssize_t ecp_rbuf_handle_flush_pts(ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, ECP2Buffer *b) {
+ssize_t ecp_rbuf_handle_timer(ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, ECP2Buffer *b) {
     ECPRBRecv *buf = conn->rbuf.recv;
+
     if (buf == NULL) return ECP_ERR;
 
-    buf->timer_pts = 0;
     msg_flush(conn, b);
     return 0;
 }
 
-int ecp_rbuf_recv_create(ECPConnection *conn, ECPRBRecv *buf, ECPRBMessage *msg, unsigned int msg_size) {
+int ecp_rbuf_recv_create(ECPConnection *conn, ECPRBRecv *buf, ECPRBMessage *msg, unsigned short msg_size) {
+    ECPRBuffer *rbuf = &buf->rbuf;
     int rv;
 
+    if (msg == NULL) return ECP_ERR;
+
     memset(buf, 0, sizeof(ECPRBRecv));
-    rv = _ecp_rbuf_init(&buf->rbuf, msg, msg_size);
-    if (rv) return rv;
+    memset(msg, 0, sizeof(ECPRBMessage) * msg_size);
 
     buf->ack_map = ECP_ACK_FULL;
     buf->ack_rate = ACK_RATE;
+    rbuf->arr.msg = msg;
+    rbuf->arr_size = msg_size;
 
 #ifdef ECP_WITH_MSGQ
     rv = ecp_conn_msgq_create(&buf->msgq);
@@ -251,22 +237,23 @@ void ecp_rbuf_recv_destroy(ECPConnection *conn) {
     ECPRBRecv *buf = conn->rbuf.recv;
 
     if (buf == NULL) return;
+
 #ifdef ECP_WITH_MSGQ
     ecp_conn_msgq_destroy(&buf->msgq);
 #endif
-
     conn->rbuf.recv = NULL;
 }
 
 int ecp_rbuf_recv_start(ECPConnection *conn, ecp_seq_t seq) {
-    int rv;
     ECPRBRecv *buf = conn->rbuf.recv;
+    ECPRBuffer *rbuf = &buf->rbuf;
+    int rv;
 
     if (buf == NULL) return ECP_ERR;
 
     seq--;
     buf->seq_ack = seq;
-    rv = _ecp_rbuf_start(&buf->rbuf, seq);
+    rv = _ecp_rbuf_start(rbuf, seq);
     if (rv) return rv;
 
 #ifdef ECP_WITH_MSGQ
@@ -283,13 +270,11 @@ int ecp_rbuf_set_hole(ECPConnection *conn, unsigned short hole_max) {
     ECPRBRecv *buf = conn->rbuf.recv;
 
     buf->hole_max = hole_max;
-    buf->hole_mask_full = ~(~((ecp_ack_t)1) << (hole_max * 2));
-    buf->hole_mask_empty = ~(~((ecp_ack_t)1) << (hole_max + 1));
 
     return ECP_OK;
 }
 
-int ecp_rbuf_set_delay(ECPConnection *conn, ecp_pts_t delay) {
+int ecp_rbuf_set_delay(ECPConnection *conn, ecp_cts_t delay) {
     ECPRBRecv *buf = conn->rbuf.recv;
 
     buf->deliver_delay = delay;
@@ -299,69 +284,83 @@ int ecp_rbuf_set_delay(ECPConnection *conn, ecp_pts_t delay) {
 
 ssize_t ecp_rbuf_store(ECPConnection *conn, ecp_seq_t seq, unsigned char *msg, size_t msg_size, ECP2Buffer *b) {
     ECPRBRecv *buf = conn->rbuf.recv;
-    ecp_seq_t ack_pkt = 0;
-    ssize_t rv;
-    int _rv;
+    ECPRBuffer *rbuf = &buf->rbuf;
     unsigned char mtype;
+    unsigned short ack_pkt = 0;
+    int do_ack = 0;
+    int _rv;
+    ssize_t rv;
 
     _rv = ecp_msg_get_type(msg, msg_size, &mtype);
     if (_rv) return _rv;
 
-    mtype &= ECP_MTYPE_MASK;
-    if ((mtype == ECP_MTYPE_RBACK) || (mtype == ECP_MTYPE_RBFLUSH)) return ecp_conn_handle_msg(conn, seq, msg, msg_size, b);
-
-    if (ECP_SEQ_LT(buf->rbuf.seq_max, seq)) {
-        ack_pkt = seq - buf->rbuf.seq_max;
-        buf->ack_pkt += ack_pkt;
-        if (buf->ack_pkt > buf->ack_rate) buf->ack_do = 1;
+    if (ECP_SEQ_LT(rbuf->seq_max, seq)) {
+        ack_pkt = seq - rbuf->seq_max;
     }
     if (ECP_SEQ_LTE(seq, buf->seq_ack)) {
         ecp_seq_t seq_offset = buf->seq_ack - seq;
         if (seq_offset < ECP_SIZE_ACKB) {
-            ecp_ack_t ack_mask = ((ecp_ack_t)1 << seq_offset);
-
-            if (ack_mask & buf->ack_map) return ECP_ERR_RBUF_DUP;
+            ecp_ack_t ack_bit = ((ecp_ack_t)1 << seq_offset);
 
-            buf->ack_map |= ack_mask;
-            buf->ack_do = buf->ack_do || ack_shift(buf);
+            if (ack_bit & buf->ack_map) return ECP_ERR_RBUF_DUP;
 
-            rv = msg_store(conn, seq, msg, msg_size, b);
+            rv = msg_store(conn, seq, msg, msg_size, mtype);
             if (rv < 0) return rv;
+
+            buf->ack_map |= ack_bit;
+            do_ack = ack_shift(buf);
         } else {
             return ECP_ERR_RBUF_DUP;
         }
     } else {
-        if ((buf->ack_map == ECP_ACK_FULL) && (seq == (ecp_seq_t)(buf->seq_ack + 1))) {
+        unsigned short msg_cnt = rbuf->seq_max - rbuf->seq_start + 1;
+
+        if ((msg_cnt == 0) && (seq == (ecp_seq_t)(buf->seq_ack + 1))) {
             if ((buf->flags & ECP_RBUF_FLAG_MSGQ) || buf->deliver_delay) {
-                rv = msg_store(conn, seq, msg, msg_size, b);
+                rv = msg_store(conn, seq, msg, msg_size, mtype);
                 if (rv < 0) return rv;
             } else {
-                ecp_conn_handle_msg(conn, seq, msg, msg_size, b);
-                rv = msg_size;
-                buf->rbuf.seq_max++;
-                buf->rbuf.seq_start++;
-                buf->rbuf.msg_start = ECP_RBUF_IDX_MASK(buf->rbuf.msg_start + 1, buf->rbuf.msg_size);
+                /* receive buffer is empty, so no need for msgq mutex lock */
+                rv = 0;
+                rbuf->seq_max++;
+                rbuf->seq_start++;
+                rbuf->idx_start = ECP_RBUF_IDX_MASK(rbuf->idx_start + 1, rbuf->arr_size);
             }
             buf->seq_ack++;
         } else {
-            rv = msg_store(conn, seq, msg, msg_size, b);
+            rv = msg_store(conn, seq, msg, msg_size, mtype);
             if (rv < 0) return rv;
 
-            buf->ack_do = buf->ack_do || ack_shift(buf);
+            do_ack = ack_shift(buf);
         }
     }
     msg_flush(conn, b);
-    if (!(mtype < ECP_MAX_MTYPE_SYS) && buf->ack_do) {
-        int _rv;
-
-        _rv = ack_send(conn);
+    if (ack_pkt) {
+        buf->ack_pkt += ack_pkt;
+        if (!do_ack && (buf->ack_pkt > buf->ack_rate)) do_ack = 1;
+    }
+    if (do_ack) {
+        ecp_seq_t seq_ack = buf->seq_ack;
+        ecp_seq_t ack_map = buf->ack_map;
+
+        /* account for missing mackets within hole_max range */
+        if (buf->hole_max && (buf->seq_ack == rbuf->seq_max)) {
+            unsigned short h_bits = buf->hole_max + 1;
+            ecp_seq_t h_mask = ~(~((ecp_seq_t)0) << h_bits);
+
+            if ((ack_map & h_mask) != h_mask) {
+                h_mask = ~(~((ecp_seq_t)0) >> h_bits);
+                seq_ack -= h_bits;
+                ack_map = (ack_map >> h_bits) | h_mask;
+            }
+        }
+        _rv = ack_send(conn, seq_ack, ack_map);
         if (_rv) return _rv;
     }
 
     return rv;
 }
 
-
 ECPFragIter *ecp_rbuf_get_frag_iter(ECPConnection *conn) {
     if (conn->rbuf.recv) return conn->rbuf.recv->frag_iter;
     return NULL;
diff --git a/ecp/src/rbuf_send.c b/ecp/src/rbuf_send.c
index faf2a7d..9f29010 100644
--- a/ecp/src/rbuf_send.c
+++ b/ecp/src/rbuf_send.c
@@ -1,7 +1,10 @@
 #include "core.h"
 #include "tr.h"
 
-#define NACK_RATE_UNIT   10000
+#define NACK_RATE_UNIT      10000
+
+#define MIN(X, Y)           (((X) < (Y)) ? (X) : (Y))
+#define MAX(X, Y)           (((X) > (Y)) ? (X) : (Y))
 
 static ssize_t flush_send(ECPConnection *conn, ECPTimerItem *ti) {
     ECPBuffer packet;
@@ -26,76 +29,83 @@ static ssize_t flush_send(ECPConnection *conn, ECPTimerItem *ti) {
         rv = ecp_timer_push(&_ti);
         if (rv) return rv;
     }
-    return ecp_rbuf_pld_send(conn, &packet, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_RBFLUSH), 0, 0);
+    return ecp_pld_send(conn, &packet, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_RBFLUSH), 0);
 }
 
-static void cc_flush(ECPConnection *conn) {
+static void cc_flush(ECPConnection *conn, unsigned char flags) {
     ECPRBSend *buf = conn->rbuf.send;
     ECPRBuffer *rbuf = &buf->rbuf;
-    ecp_seq_t pkt_buf_cnt = rbuf->seq_max - rbuf->seq_start + 1;
-    ecp_win_t pkt_cc_cnt = buf->win_size > buf->in_transit ? buf->win_size - buf->in_transit : 0;
-    int pkt_to_send = pkt_buf_cnt < pkt_cc_cnt ? pkt_buf_cnt : pkt_cc_cnt;
-    int i;
+    unsigned short idx;
+    int rv;
 
-    ECPTimerItem ti[ECP_MAX_TIMER];
-    unsigned short max_t = 0;
+    rv = _ecp_rbuf_msg_idx(rbuf, buf->seq_cc, &idx);
+    if (rv) return;
 
-    if (pkt_to_send) {
-        unsigned int idx = _ecp_rbuf_msg_idx(rbuf, buf->seq_cc);
-        unsigned int _idx = idx;
+    while (ECP_SEQ_LTE(buf->seq_cc, rbuf->seq_max)) {
+        ECPRBTimerItem *ti;
+        ECPBuffer packet;
 
-        for (i=0; i<pkt_to_send; i++) {
-            if (!(rbuf->msg[_idx].flags & ECP_RBUF_FLAG_IN_CCONTROL)) break;
-            rbuf->msg[_idx].flags &= ~ECP_RBUF_FLAG_IN_CCONTROL;
-            if (rbuf->msg[_idx].idx_t != -1) {
-                ECPRBTimer *timer = &buf->timer;
-                ECPRBTimerItem *item = &timer->item[rbuf->msg[_idx].idx_t];
-
-                item->occupied = 0;
-                ti[max_t] = item->item;
-                rbuf->msg[_idx].idx_t = max_t;
-                max_t++;
-            }
-            _idx = ECP_RBUF_IDX_MASK(_idx + 1, rbuf->msg_size);
-        }
-        pkt_to_send = i;
-        _idx = idx;
+        if ((buf->cnt_cc == 0) || (buf->in_transit >= buf->win_size)) break;
 
+        if ((rbuf->arr.pkt[idx].flags & ECP_RBUF_FLAG_IN_RBUF) && !(rbuf->arr.pkt[idx].flags & ECP_RBUF_FLAG_SKIP)) {
 #ifdef ECP_WITH_PTHREAD
-        pthread_mutex_unlock(&buf->mutex);
+            pthread_mutex_unlock(&buf->mutex);
 #endif
 
-        for (i=0; i<pkt_to_send; i++) {
-            ECPBuffer packet;
+            ti = rbuf->arr.pkt[idx].timer;
+            if (ti) ecp_timer_push(&ti->item);
+            packet.buffer = rbuf->arr.pkt[idx].buf;
+            packet.size = ECP_MAX_PKT;
+            ecp_pkt_send(conn->sock, &conn->node.addr, &packet, rbuf->arr.pkt[idx].size, flags);
 
-            if (rbuf->msg[_idx].idx_t != -1) ecp_timer_push(&ti[rbuf->msg[_idx].idx_t]);
-            packet.buffer = rbuf->msg[_idx].msg;
-            packet.size = rbuf->msg[_idx].size;
-            ecp_pkt_send(conn->sock, &conn->node.addr, &packet, rbuf->msg[_idx].size, 0);
-            _idx = ECP_RBUF_IDX_MASK(_idx + 1, rbuf->msg_size);
-        }
+#ifdef ECP_WITH_PTHREAD
+            pthread_mutex_lock(&buf->mutex);
+#endif
 
+            if (ti) {
 #ifdef ECP_WITH_PTHREAD
-        pthread_mutex_lock(&buf->mutex);
+                pthread_mutex_lock(&buf->timer->mutex);
 #endif
+                ti->empty = 1;
+#ifdef ECP_WITH_PTHREAD
+                pthread_mutex_lock(&buf->timer->mutex);
+#endif
+            }
 
-        buf->in_transit += (ecp_win_t)pkt_to_send;
-        buf->cnt_cc -= (ecp_win_t)pkt_to_send;
-        buf->seq_cc += (ecp_seq_t)pkt_to_send;
+            buf->cnt_cc--;
+            buf->in_transit++;
+        }
+        if (!(buf->flags & ECP_RBUF_FLAG_RELIABLE)) {
+            rbuf->arr.pkt[idx].flags = 0;
+            // if (rbuf->arr.pkt[idx].flags == 0);
+        }
+        buf->seq_cc++;
+        idx = ECP_RBUF_IDX_MASK(idx + 1, rbuf->arr_size);
+    }
+    if (!(buf->flags & ECP_RBUF_FLAG_RELIABLE)) {
+        rbuf->seq_start = buf->seq_cc;
+        rbuf->idx_start = idx;
     }
 }
 
 ssize_t ecp_rbuf_handle_ack(ECPConnection *conn, ecp_seq_t seq, unsigned char mtype, unsigned char *msg, ssize_t size, ECP2Buffer *b) {
     ECPRBSend *buf;
+    ECPRBuffer *rbuf;
     ssize_t rsize = sizeof(ecp_seq_t)+sizeof(ecp_ack_t);
     ecp_seq_t seq_ack = 0;
     ecp_ack_t ack_map = 0;
-    int i;
+    ecp_seq_t seq_start;
+    ecp_seq_t seq_max;
+    unsigned short idx;
+    unsigned short msg_cnt;
     int do_flush = 0;
-    int rv = ECP_OK;
+    int i;
+    int rv;
 
     buf = conn->rbuf.send;
     if (buf == NULL) return size;
+
+    rbuf = &buf->rbuf;
     if (size < 0) return size;
     if (size < rsize) return ECP_ERR;
 
@@ -111,89 +121,108 @@ ssize_t ecp_rbuf_handle_ack(ECPConnection *conn, ecp_seq_t seq, unsigned char mt
         (msg[7]);
 
     ecp_tr_release(b->packet, 1);
-    ecp_tr_flag_set(ECP_SEND_FLAG_MORE);
 
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_lock(&buf->mutex);
 #endif
 
-    ECPRBuffer *rbuf = &buf->rbuf;
-    int idx = _ecp_rbuf_msg_idx(rbuf, seq_ack);
-    if (idx < 0) rv = idx;
+    seq_max = (buf->cnt_cc ? buf->seq_cc - 1 : rbuf->seq_max);
+    if (ECP_SEQ_LT(seq_max, seq_ack)) return ECP_ERR;
 
-    if (!rv) {
-        seq_ack++;
-        if (buf->flags & ECP_RBUF_FLAG_CCONTROL) buf->in_transit = buf->cnt_cc ? buf->seq_cc - seq_ack : rbuf->seq_max - seq_ack + 1;
+    if (buf->flags & ECP_RBUF_FLAG_RELIABLE) {
+        rv = _ecp_rbuf_msg_idx(rbuf, seq_ack, &idx);
+        if (rv) goto handle_ack_fin;
+    }
 
-        if (ack_map != ECP_ACK_FULL) {
-            int nack_first = 0;
-            unsigned int msg_start;
-            ecp_seq_t seq_start;
-            ecp_win_t nack_cnt = 0;
+    if (buf->flags & ECP_RBUF_FLAG_CCONTROL) {
+        buf->in_transit = seq_max - seq_ack;
+    }
 
-            seq_ack -= ECP_SIZE_ACKB;
+    if (ack_map != ECP_ACK_FULL) {
+        ecp_ack_t ack_mask = (ecp_ack_t)1 << (ECP_SIZE_ACKB - 1);
+        unsigned short nack_cnt = 0;
+        int nack_first = 0;
+
+        seq_ack -= (ECP_SIZE_ACKB - 1);
+        if (buf->flags & ECP_RBUF_FLAG_RELIABLE) {
+            rv = _ecp_rbuf_msg_idx(rbuf, seq_ack, &idx);
+            if (rv) goto handle_ack_fin;
+        }
 
 #ifdef ECP_WITH_PTHREAD
-            pthread_mutex_unlock(&buf->mutex);
+        pthread_mutex_unlock(&buf->mutex);
 #endif
 
-            for (i=0; i<ECP_SIZE_ACKB; i++) {
-                if ((ack_map & ((ecp_ack_t)1 << (ECP_SIZE_ACKB - i - 1))) == 0) {
+        for (i=0; i<ECP_SIZE_ACKB; i++) {
+            if ((ack_map & ack_mask) == 0) {
+                if (ECP_SEQ_LT(buf->seq_nack, seq_ack)) {
                     nack_cnt++;
-                    if (buf->flags & ECP_RBUF_FLAG_RELIABLE) {
-                        unsigned int _idx = ECP_RBUF_IDX_MASK(idx + 1 - ECP_SIZE_ACKB + i, rbuf->msg_size);
-                        if ((rbuf->msg[_idx].size == 0) || (rbuf->msg[_idx].flags & ECP_RBUF_FLAG_SYS)) {
-                            ECPBuffer packet;
-                            ECPBuffer payload;
-                            unsigned char pkt_buf[ECP_SIZE_PKT_BUF(0, ECP_MTYPE_NOP, conn)];
-                            unsigned char pld_buf[ECP_SIZE_PLD_BUF(0, ECP_MTYPE_NOP, conn)];
-
-                            packet.buffer = pkt_buf;
-                            packet.size = ECP_SIZE_PKT_BUF(0, ECP_MTYPE_NOP, conn);
-                            payload.buffer = pld_buf;
-                            payload.size = ECP_SIZE_PLD_BUF(0, ECP_MTYPE_NOP, conn);
-
-                            ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_NOP);
-                            ecp_rbuf_pld_send(conn, &packet, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_NOP), 0, seq_ack + i);
-                        } else {
-                            ECPBuffer packet;
-                            packet.buffer = rbuf->msg[_idx].msg;
-                            packet.size = rbuf->msg[_idx].size;
-                            ecp_pkt_send(conn->sock, &conn->node.addr, &packet, rbuf->msg[_idx].size, 0);
-                        }
-                        if (!nack_first) {
-                            nack_first = 1;
-                            seq_start = seq_ack + i;
-                            msg_start = _idx;
+                    buf->seq_nack = seq_ack;
+                }
+
+                if (buf->flags & ECP_RBUF_FLAG_RELIABLE) {
+                    if (!(rbuf->arr.pkt[idx].flags & ECP_RBUF_FLAG_IN_RBUF) || (rbuf->arr.pkt[idx].flags & ECP_RBUF_FLAG_SKIP)) {
+                        ECPBuffer packet;
+                        ECPBuffer payload;
+                        unsigned char pkt_buf[ECP_SIZE_PKT_BUF(0, ECP_MTYPE_NOP, conn)];
+                        unsigned char pld_buf[ECP_SIZE_PLD_BUF(0, ECP_MTYPE_NOP, conn)];
+
+                        packet.buffer = pkt_buf;
+                        packet.size = ECP_SIZE_PKT_BUF(0, ECP_MTYPE_NOP, conn);
+                        payload.buffer = pld_buf;
+                        payload.size = ECP_SIZE_PLD_BUF(0, ECP_MTYPE_NOP, conn);
+
+                        ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_NOP);
+                        ecp_rbuf_pld_send(conn, &packet, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_NOP), ECP_SEND_FLAG_MORE, seq_ack);
+                    } else {
+                        ECPBuffer packet;
+
+                        packet.buffer = rbuf->arr.pkt[idx].buf;
+                        packet.size = ECP_MAX_PKT;
+                        ecp_pkt_send(conn->sock, &conn->node.addr, &packet, rbuf->arr.pkt[idx].size, ECP_SEND_FLAG_MORE);
+                        if (buf->flags & ECP_RBUF_FLAG_CCONTROL) {
+                            buf->in_transit++;
                         }
                     }
+                    if (!nack_first) {
+                        nack_first = 1;
+                        seq_start = seq_ack;
+                    }
                 }
             }
+            seq_ack++;
+            ack_mask = ack_mask >> 1;
+            if (buf->flags & ECP_RBUF_FLAG_RELIABLE) idx = ECP_RBUF_IDX_MASK(idx + 1, rbuf->arr_size);
+        }
 
 #ifdef ECP_WITH_PTHREAD
-            pthread_mutex_lock(&buf->mutex);
+        pthread_mutex_lock(&buf->mutex);
 #endif
 
-            if (buf->flags & ECP_RBUF_FLAG_CCONTROL) buf->in_transit += nack_cnt;
-            buf->nack_rate = (buf->nack_rate * 7 + ((ECP_SIZE_ACKB - nack_cnt) * NACK_RATE_UNIT) / ECP_SIZE_ACKB) / 8;
-            if (buf->flags & ECP_RBUF_FLAG_RELIABLE) {
-                rbuf->seq_start = seq_start;
-                rbuf->msg_start = msg_start;
-            } else {
-                rbuf->seq_start = seq_ack + ECP_SIZE_ACKB;
-                rbuf->msg_start = ECP_RBUF_IDX_MASK(idx + 1, rbuf->msg_size);
-            }
-        } else {
-            buf->nack_rate = (buf->nack_rate * 7) / 8;
-            rbuf->seq_start = seq_ack;
-            rbuf->msg_start = ECP_RBUF_IDX_MASK(idx + 1, rbuf->msg_size);
-        }
-        if (buf->flush) {
-            if (ECP_SEQ_LT(buf->seq_flush, rbuf->seq_start)) buf->flush = 0;
-            if (buf->flush) do_flush = 1;
+        buf->nack_rate = (buf->nack_rate * 7 + ((ECP_SIZE_ACKB - nack_cnt) * NACK_RATE_UNIT) / ECP_SIZE_ACKB) / 8;
+    } else {
+        buf->nack_rate = (buf->nack_rate * 7) / 8;
+        seq_start = seq_ack + 1;
+    }
+
+    if (buf->flags & ECP_RBUF_FLAG_RELIABLE) {
+        msg_cnt = seq_start - rbuf->seq_start;
+        idx = rbuf->idx_start;
+        for (i=0; i<msg_cnt; i++) {
+            rbuf->arr.pkt[idx].flags = 0;
+            // if (rbuf->arr.pkt[idx].flags == 0);
+            idx = ECP_RBUF_IDX_MASK(idx + 1, rbuf->arr_size);
         }
-        if (buf->cnt_cc) cc_flush(conn);
+        rbuf->seq_start = seq_start;
+        rbuf->idx_start = idx;
     }
+    if (buf->flush) {
+        if (ECP_SEQ_LT(buf->seq_flush, rbuf->seq_start)) buf->flush = 0;
+        if (buf->flush) do_flush = 1;
+    }
+    if (buf->cnt_cc) cc_flush(conn, ECP_SEND_FLAG_MORE);
+
+handle_ack_fin:
 
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_unlock(&buf->mutex);
@@ -204,21 +233,27 @@ ssize_t ecp_rbuf_handle_ack(ECPConnection *conn, ecp_seq_t seq, unsigned char mt
 
         _rv = flush_send(conn, NULL);
         if (_rv < 0) rv = _rv;
+    } else {
+        // ecp_tr_nomore();
     }
 
-    ecp_tr_flag_clear(ECP_SEND_FLAG_MORE);
     ecp_tr_release(b->packet, 0);
 
     if (rv) return rv;
     return rsize;
 }
 
-int ecp_rbuf_send_create(ECPConnection *conn, ECPRBSend *buf, ECPRBMessage *msg, unsigned int msg_size) {
+int ecp_rbuf_send_create(ECPConnection *conn, ECPRBSend *buf, ECPRBPacket *pkt, unsigned short pkt_size) {
+    ECPRBuffer *rbuf = &buf->rbuf;
     int rv;
 
+    if (pkt == NULL) return ECP_ERR;
+
     memset(buf, 0, sizeof(ECPRBRecv));
-    rv = _ecp_rbuf_init(&buf->rbuf, msg, msg_size);
-    if (rv) return rv;
+    memset(pkt, 0, sizeof(ECPRBPacket) * pkt_size);
+
+    rbuf->arr.pkt = pkt;
+    rbuf->arr_size = pkt_size;
 
 #ifdef ECP_WITH_PTHREAD
     rv = pthread_mutex_init(&buf->mutex, NULL);
@@ -243,10 +278,12 @@ void ecp_rbuf_send_destroy(ECPConnection *conn) {
 
 int ecp_rbuf_send_start(ECPConnection *conn) {
     ECPRBSend *buf = conn->rbuf.send;
+    ECPRBuffer *rbuf = &buf->rbuf;
 
     if (buf == NULL) return ECP_ERR;
 
-    return _ecp_rbuf_start(&buf->rbuf, conn->seq_out);
+    buf->seq_nack = conn->seq_out;
+    return _ecp_rbuf_start(rbuf, conn->seq_out);
 }
 
 int ecp_rbuf_set_wsize(ECPConnection *conn, ecp_win_t size) {
@@ -259,7 +296,7 @@ int ecp_rbuf_set_wsize(ECPConnection *conn, ecp_win_t size) {
 #endif
 
     buf->win_size = size;
-    if (buf->cnt_cc) cc_flush(conn);
+    if (buf->cnt_cc) cc_flush(conn, 0);
 
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_unlock(&buf->mutex);
diff --git a/ecp/src/vconn/vconn.c b/ecp/src/vconn/vconn.c
index d60f5f2..d3eec44 100644
--- a/ecp/src/vconn/vconn.c
+++ b/ecp/src/vconn/vconn.c
@@ -64,7 +64,7 @@ static ssize_t _vconn_send_open(ECPConnection *conn, ECPTimerItem *ti) {
     payload.size = ECP_SIZE_PLD_BUF(0, ECP_MTYPE_KGET_REQ, conn);
 
     ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_KGET_REQ);
-    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, NULL, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_KGET_REQ), 0, ti);
+    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_KGET_REQ), 0, ti);
 }
 
 static ssize_t vconn_send_open(ECPConnection *conn) {
@@ -188,7 +188,7 @@ static ssize_t vconn_handle_relay(ECPConnection *conn, ecp_seq_t seq, unsigned c
     if (b == NULL) return ECP_ERR;
 
     if (size < 0) return size;
-    if (size < ECP_MIN_PKT) return ECP_ERR_MIN_PKT;
+    if (size < ECP_MIN_PKT) return ECP_ERR;
 
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_lock(&key_perma_mutex);
@@ -337,7 +337,7 @@ static ssize_t vlink_handle_relay(ECPConnection *conn, ecp_seq_t seq, unsigned c
     if (b == NULL) return ECP_ERR;
 
     if (size < 0) return size;
-    if (size < ECP_MIN_PKT) return ECP_ERR_MIN_PKT;
+    if (size < ECP_MIN_PKT) return ECP_ERR;
 
 #ifdef ECP_WITH_PTHREAD
     pthread_mutex_lock(&key_next_mutex);
@@ -456,7 +456,7 @@ ssize_t ecp_pack(ECPContext *ctx, ECPConnection *parent, ECPBuffer *packet, ECPP
         if (payload->size < rv+hdr_size) return ECP_ERR;
         memcpy(payload->buffer, packet->buffer, rv+hdr_size);
 
-        return ecp_pack_conn(parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, NULL, payload, rv+hdr_size, addr);
+        return ecp_pack_conn(parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, payload, rv+hdr_size, addr, NULL);
     } else {
         return _ecp_pack(ctx, packet->buffer, packet->size, pkt_meta, payload->buffer, pld_size);
     }
@@ -487,7 +487,7 @@ ssize_t ecp_pack(ECPContext *ctx, ECPConnection *parent, ECPBuffer *packet, ECPP
         rv = _ecp_pack(ctx, _payload.buffer+hdr_size, _payload.size-hdr_size, pkt_meta, payload->buffer, pld_size);
         if (rv < 0) return rv;
 
-        return ecp_pack_conn(parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, NULL, &_payload, rv+hdr_size, addr);
+        return ecp_pack_conn(parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, &_payload, rv+hdr_size, addr, NULL);
     } else {
         return _ecp_pack(ctx, packet->buffer, packet->size, pkt_meta, payload->buffer, pld_size);
     }
@@ -498,7 +498,7 @@ ssize_t ecp_pack(ECPContext *ctx, ECPConnection *parent, ECPBuffer *packet, ECPP
 #ifdef ECP_MEM_TINY
 /* Memory limited version */
 
-ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr) {
+ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr, ECPSeqItem *si) {
     if ((packet == NULL) || (packet->buffer == NULL)) return ECP_ERR;
     if ((payload == NULL) || (payload->buffer == NULL)) return ECP_ERR;
 
@@ -513,21 +513,21 @@ ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_id
         hdr_size = vconn_set_msg(conn->parent, packet, mtype);
         if (hdr_size < 0) return hdr_size;
 
-        rv = _ecp_pack_conn(conn, packet->buffer+hdr_size, packet->size-hdr_size, s_idx, c_idx, si, payload->buffer, pld_size, NULL);
+        rv = _ecp_pack_conn(conn, packet->buffer+hdr_size, packet->size-hdr_size, s_idx, c_idx, payload->buffer, pld_size, NULL, si);
         if (rv < 0) return rv;
 
         if (payload->size < rv+hdr_size) return ECP_ERR;
         memcpy(payload->buffer, packet->buffer, rv+hdr_size);
 
-        return ecp_pack_conn(conn->parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, NULL, payload, rv+hdr_size, addr);
+        return ecp_pack_conn(conn->parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, payload, rv+hdr_size, addr, NULL);
     } else {
-        return _ecp_pack_conn(conn, packet->buffer, packet->size, s_idx, c_idx, si, payload->buffer, pld_size, addr);
+        return _ecp_pack_conn(conn, packet->buffer, packet->size, s_idx, c_idx, payload->buffer, pld_size, addr, si);
     }
 }
 
 #else
 
-ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPSeqItem *si, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr) {
+ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_idx, unsigned char c_idx, ECPBuffer *payload, size_t pld_size, ECPNetAddr *addr, ECPSeqItem *si) {
     if ((packet == NULL) || (packet->buffer == NULL)) return ECP_ERR;
     if ((payload == NULL) || (payload->buffer == NULL)) return ECP_ERR;
 
@@ -547,12 +547,12 @@ ssize_t ecp_pack_conn(ECPConnection *conn, ECPBuffer *packet, unsigned char s_id
         hdr_size = vconn_set_msg(conn->parent, &_payload, mtype);
         if (hdr_size < 0) return hdr_size;
 
-        rv = _ecp_pack_conn(conn, _payload.buffer+hdr_size, _payload.size-hdr_size, s_idx, c_idx, si, payload->buffer, pld_size, NULL);
+        rv = _ecp_pack_conn(conn, _payload.buffer+hdr_size, _payload.size-hdr_size, s_idx, c_idx, payload->buffer, pld_size, NULL, si);
         if (rv < 0) return rv;
 
-        return ecp_pack_conn(conn->parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, NULL, &_payload, rv+hdr_size, addr);
+        return ecp_pack_conn(conn->parent, packet, ECP_ECDH_IDX_INV, ECP_ECDH_IDX_INV, &_payload, rv+hdr_size, addr, NULL);
     } else {
-        return _ecp_pack_conn(conn, packet->buffer, packet->size, s_idx, c_idx, si, payload->buffer, pld_size, addr);
+        return _ecp_pack_conn(conn, packet->buffer, packet->size, s_idx, c_idx, payload->buffer, pld_size, addr, si);
     }
 }
 
@@ -662,7 +662,7 @@ static ssize_t _vconn_send_kget(ECPConnection *conn, ECPTimerItem *ti) {
     payload.size = ECP_SIZE_PLD_BUF(0, ECP_MTYPE_KGET_REQ, conn);
 
     ecp_pld_set_type(payload.buffer, payload.size, ECP_MTYPE_KGET_REQ);
-    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, NULL, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_KGET_REQ), 0, ti);
+    return _ecp_pld_send(conn, &packet, ECP_ECDH_IDX_PERMA, ECP_ECDH_IDX_INV, &payload, ECP_SIZE_PLD(0, ECP_MTYPE_KGET_REQ), 0, ti);
 }
 
 int ecp_vconn_open(ECPConnection *conn, ECPNode *conn_node, ECPVConnOut vconn[], ECPNode vconn_node[], int size) {
diff --git a/ecp/test/frag.c b/ecp/test/frag.c
index 73e45cb..70b20de 100644
--- a/ecp/test/frag.c
+++ b/ecp/test/frag.c
@@ -46,7 +46,7 @@ ssize_t handle_msg_c(ECPConnection *conn, ecp_seq_t sq, unsigned char t, unsigne
     printf("MSG C:%s size:%ld\n", p, s);
 
     ECPRBuffer *rbuf = &conn->rbuf.recv->rbuf;
-    printf("RBUF: %d %d %d %d\n", rbuf->seq_start, rbuf->seq_max, rbuf->msg_start, rbuf->msg_size);
+    printf("RBUF: %d %d %d %d\n", rbuf->seq_start, rbuf->seq_max, rbuf->idx_start, rbuf->arr_size);
     return s;
 }