diff --git a/src/routing_layer/etcp_router.c b/src/routing_layer/etcp_router.c
index 1eb6124d..ccaac870 100644
--- a/src/routing_layer/etcp_router.c
+++ b/src/routing_layer/etcp_router.c
@@ -34,6 +34,7 @@ static void router_try_assembly(struct ETCP_ROUTER_CONN* rconn, struct ETCP_CONN
 static void router_deliver(struct ETCP_ROUTER_CONN* rconn, struct ETCP_CONN* conn, const uint8_t* wire, size_t wire_len);
 static void router_send_ctrl(struct ETCP_ROUTER_CONN* rconn, uint8_t flag_bits);
 static void router_send_rst(struct ETCP_ROUTER_CONN* rconn);
+static void router_restart_send(struct ETCP_ROUTER_CONN* rconn);
 static struct ETCP_CONN* router_send_conn(struct ETCP_ROUTER_CONN* rconn);
 static void router_send_kick(struct ETCP_ROUTER_CONN* rconn);
 static void router_send_drain_cb(struct ll_queue* q, void* arg);
@@ -49,7 +50,7 @@ static void router_conn_reset(struct ETCP_ROUTER_CONN* rconn);
 static void free_entry(struct ll_entry* e) { queue_dgram_free(e); queue_entry_free(e); }
 static void router_handle_ack(struct UTUN_INSTANCE* inst, struct ETCP_ROUTER_CONN* rconn, uint32_t seq, uint64_t src_node_id, uint16_t ack_ts);
 static void router_forward_transit(struct UTUN_INSTANCE* inst, struct ll_entry* entry, struct SVC_ROUTE_HDR* hdr);
-static int  router_check_peer_restart(struct UTUN_INSTANCE* inst, struct ETCP_ROUTER_CONN** prconn, struct SVC_ROUTE_HDR* hdr);
+static int  router_check_peer_restart(struct UTUN_INSTANCE* inst, struct ETCP_ROUTER_CONN** prconn, struct SVC_ROUTE_HDR* hdr, size_t wire_len);
 static void router_handle_data_packet(struct ETCP_ROUTER_CONN* rconn, struct ETCP_CONN* conn, uint32_t seq, const uint8_t* wire, size_t wire_len);
 static void router_retransmit_one(struct ETCP_ROUTER_CONN* rconn, struct ROUTER_INFLIGHT* inf);
 static void router_retrans_schedule(struct ETCP_ROUTER_CONN* rconn);
@@ -279,6 +280,33 @@ static void router_send_rst(struct ETCP_ROUTER_CONN* rconn) {
     }
 }
 
+// Рестарт только отправки (по RST от пира): сброс tx-состояния, очистка send_q/inflight_q.
+// Приёмная сторона (rx) и сервис не трогаются. Повторные RST игнорируются через send_restart_pending.
+static void router_restart_send(struct ETCP_ROUTER_CONN* rconn) {
+    struct UTUN_INSTANCE* inst = rconn->inst;
+    if (rconn->retrans_timer)  { uasync_cancel_timeout(inst->ua, rconn->retrans_timer); rconn->retrans_timer = NULL; }
+    if (rconn->watchdog_timer) { uasync_cancel_timeout(inst->ua, rconn->watchdog_timer); rconn->watchdog_timer = NULL; }
+    {
+        struct ETCP_CONN* c = router_send_conn(rconn);
+        if (c && c->send_input_q) queue_waiter_cancel(c->send_input_q, &rconn->send_waiter);
+        memset(&rconn->send_waiter, 0, sizeof(rconn->send_waiter));
+    }
+    struct ll_entry* f;
+    if (rconn->send_q) {
+        while ((f = queue_data_get(rconn->send_q)) != NULL) { queue_dgram_free(f); queue_entry_free(f); }
+    }
+    if (rconn->inflight_q) {
+        while ((f = queue_data_get(rconn->inflight_q)) != NULL) {
+            struct ROUTER_INFLIGHT* inf = (struct ROUTER_INFLIGHT*)f;
+            if (inf->dgram) u_free(inf->dgram);
+            u_free(inf);
+        }
+    }
+    rconn->tx_seq = 0; rconn->tx_acked = 0; rconn->start_sent = 0;
+    rconn->send_blocked = 0; rconn->no_ack_count = 0; rconn->last_ack_changed_tb = 0;
+    rconn->send_restart_pending = 1;
+}
+
 static struct ETCP_CONN* loopback_conn(struct UTUN_INSTANCE* inst) {
     static struct ETCP_CONN c;
     memset(&c, 0, sizeof(c));
@@ -345,6 +373,7 @@ static void router_conn_free_queues(struct ETCP_ROUTER_CONN* rconn) {
         queue_resume_callback(rconn->incoming_q);
         queue_free(rconn->incoming_q); rconn->incoming_q = NULL;
     }
+    if (rconn->last_start_dgram) { u_free(rconn->last_start_dgram); rconn->last_start_dgram = NULL; rconn->last_start_dgram_len = 0; }
 }
 
 // Пересоздать очереди и сбросить всё состояние rconn (кроме identity: group/remote/svc/ll.data/inst/sess_id/last_dgram_ts).
@@ -373,7 +402,7 @@ static void router_conn_reset(struct ETCP_ROUTER_CONN* rconn) {
 
     rconn->tx_seq = 0; rconn->rx_seq = 0; rconn->tx_acked = 0;
     rconn->last_sent_ack_seq = 0; rconn->last_ack_sent_tb = 0;
-    rconn->send_blocked = 0; rconn->start_sent = 0; rconn->peer_sync_done = 0;
+    rconn->send_blocked = 0; rconn->start_sent = 0; rconn->peer_sync_done = 0; rconn->send_restart_pending = 0;
     rconn->no_route = 0; rconn->no_route_timer = NULL; rconn->no_ack_count = 0; rconn->closed = 0;
     rconn->c_pkts_sent = 0; rconn->c_pkts_send_err = 0; rconn->c_pkts_rcvd = 0;
     rconn->c_ack_sent = 0; rconn->c_ack_recv = 0; rconn->c_retrans_done = 0;
@@ -410,6 +439,7 @@ static void router_set_no_route(struct ETCP_ROUTER_CONN* rconn) {
 static void router_send_kick(struct ETCP_ROUTER_CONN* rconn) {
     if (rconn->closed || rconn->no_route) return;
     if (queue_entry_count(rconn->send_q) == 0) return;
+    if (!rconn->start_sent && queue_entry_count(rconn->inflight_q) > 0) { rconn->send_blocked = 1; return; }
     if (queue_entry_count(rconn->inflight_q) >= (int)router_effective_max_inflight(rconn)) {
         rconn->send_blocked = 1;
         return;
@@ -468,6 +498,7 @@ static void router_send_drain_cb(struct ll_queue* q, void* arg) {
             if (!rconn->retrans_timer) router_retrans_schedule(rconn);
         }
         router_track_inflight_state(rconn);
+        if (!rconn->start_sent) { rconn->send_blocked = 1; return; }
     }
 
     if (queue_entry_count(rconn->send_q) == 0) { rconn->send_blocked = 0; router_send_watchdog_disarm(rconn); return; }
@@ -487,7 +518,7 @@ static void router_send_watchdog_cb(void* arg) {
     rconn->watchdog_timer = NULL;
     if (rconn->closed) return;
     if (queue_entry_count(rconn->send_q) == 0) return;
-    if (!rconn->no_route
+    if (!rconn->no_route && !rconn->send_blocked
         && queue_entry_count(rconn->inflight_q) < (int)router_effective_max_inflight(rconn)
         && !rconn->send_waiter.internal && !rconn->send_waiter.call_soon_id) {
         DEBUG_ERROR(DEBUG_CATEGORY_ETCPROUTE, "router watchdog: send_q stalled svc_id=%u send_q=%d inflight=%d blocked=%d — force kick",
@@ -940,7 +971,7 @@ static void router_handle_ack(struct UTUN_INSTANCE* inst, struct ETCP_ROUTER_CON
     if ((int32_t)(seq - rconn->tx_acked) >= 0) {
         uint32_t old_acked = rconn->tx_acked;
         rconn->tx_acked = seq;
-        if (rconn->tx_acked > 0) rconn->start_sent = 1;// первый ACK подтвердил seq 0 — сессия больше не «новая»
+        if (rconn->tx_acked > 0) { rconn->start_sent = 1; rconn->send_restart_pending = 0; }// первый ACK подтвердил seq 0 — сессия больше не «новая»
         uint32_t clean_seq = old_acked;
         while ((int32_t)(clean_seq - rconn->tx_acked) < 0) {
             struct ROUTER_INFLIGHT* inf = (struct ROUTER_INFLIGHT*)queue_find_data_by_index(rconn->inflight_q, &clean_seq);
@@ -1022,17 +1053,25 @@ static void router_forward_transit(struct UTUN_INSTANCE* inst, struct ll_entry*
 }
 
 static int router_check_peer_restart(struct UTUN_INSTANCE* inst, struct ETCP_ROUTER_CONN** prconn,
-                                      struct SVC_ROUTE_HDR* hdr) {
+                                      struct SVC_ROUTE_HDR* hdr, size_t wire_len) {
     struct ETCP_ROUTER_CONN* rconn = *prconn;
-    if ((hdr->flags & ROUTER_FLAG_START) && rconn->rx_seq > 0) {
-        DEBUG_INFO(DEBUG_CATEGORY_ETCPROUTE,
-                   "router: peer restart svc_id=%u from %016llx",
-                   hdr->svc_id, (unsigned long long)hdr->src_node_id);
-        etcp_router_conn_restart(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
-        *prconn = etcp_router_conn_get(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
-        if (!*prconn) return -1;
-        rconn = *prconn;
+    if (!(hdr->flags & ROUTER_FLAG_START)) return 0;   // не START — не рестарт
+    if (!rconn->peer_sync_done) return 0;              // чистый: принимаем как первый пакет сеанса
+
+    // dirty + START: дедуп по payload. Ретрансмит уже принятого init-пакета побайтно идентичен —
+    // это НЕ новый сеанс, рестарт не делаем (пере-ACK сделает dup-ветка в router_handle_data_packet).
+    if (rconn->last_start_dgram && rconn->last_start_dgram_len == wire_len
+        && memcmp(rconn->last_start_dgram, hdr, wire_len) == 0) {
+        return 0;
     }
+
+    DEBUG_INFO(DEBUG_CATEGORY_ETCPROUTE,
+               "router: peer restart svc_id=%u from %016llx",
+               hdr->svc_id, (unsigned long long)hdr->src_node_id);
+    etcp_router_conn_restart(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
+    *prconn = etcp_router_conn_get(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
+    if (!*prconn) return -1;
+    rconn = *prconn;
     return 0;
 }
 
@@ -1041,7 +1080,17 @@ static void router_handle_data_packet(struct ETCP_ROUTER_CONN* rconn, struct ETC
     rconn->recv_conn = conn;
     rconn->last_dgram_ts = get_current_timestamp();
 
-    if (!rconn->peer_sync_done) { rconn->peer_sync_done = 1; rconn->rx_seq = seq; }
+    if (!rconn->peer_sync_done) {
+        rconn->peer_sync_done = 1;
+        rconn->rx_seq = seq;
+        // сохранить init-пакет (START) для дедупа ретрансмитов
+        if (((const struct SVC_ROUTE_HDR*)wire)->flags & ROUTER_FLAG_START) {
+            if (rconn->last_start_dgram) u_free(rconn->last_start_dgram);
+            rconn->last_start_dgram = u_malloc(wire_len);
+            if (rconn->last_start_dgram) { memcpy(rconn->last_start_dgram, wire, wire_len); rconn->last_start_dgram_len = wire_len; }
+            else rconn->last_start_dgram_len = 0;
+        }
+    }
 
     {// SEQ out of bounds
         int32_t d = (int32_t)(seq - rconn->rx_seq);
@@ -1100,8 +1149,17 @@ static void etcp_router_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry)
     struct ETCP_ROUTER_CONN* rconn = router_conn_find(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
 
     if (pl_len == 0 && (hdr->flags & ROUTER_FLAG_RST)) {
-        // Пир отклонил нашу «старую» сессию — сброс локального состояния (пере-шлём START).
-        if (rconn) etcp_router_conn_restart(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
+        // Пир просит переинициализировать нашу отправку (его приём «чистый»).
+        if (rconn) {
+            if (rconn->send_restart_pending) {
+                DEBUG_DEBUG(DEBUG_CATEGORY_ETCPROUTE, "router: RST (дубль) от %016llx svc_id=%u — игнор",
+                            (unsigned long long)hdr->src_node_id, hdr->svc_id);
+            } else {
+                DEBUG_INFO(DEBUG_CATEGORY_ETCPROUTE, "router: RST от %016llx svc_id=%u — рестарт отправки",
+                           (unsigned long long)hdr->src_node_id, hdr->svc_id);
+                router_restart_send(rconn);
+            }
+        }
         free_entry(entry); return;
     }
     if (pl_len == 0 && (hdr->flags & ROUTER_FLAG_CLOSE)) {
@@ -1114,7 +1172,7 @@ static void etcp_router_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry)
         rconn = etcp_router_conn_get(inst, hdr->group_id, hdr->src_node_id, hdr->svc_id);
         if (!rconn) { free_entry(entry); return; }
     }
-    if (router_check_peer_restart(inst, &rconn, hdr) != 0) { free_entry(entry); return; }
+    if (router_check_peer_restart(inst, &rconn, hdr, entry->len) != 0) { free_entry(entry); return; }
 
     // Сервер после рестарта «ждёт START»: пришёл не-START пакет от старой сессии → RST.
     if (!rconn->peer_sync_done && !(hdr->flags & ROUTER_FLAG_START)) {
diff --git a/src/routing_layer/etcp_router.h b/src/routing_layer/etcp_router.h
index ad231366..8169d1ff 100644
--- a/src/routing_layer/etcp_router.h
+++ b/src/routing_layer/etcp_router.h
@@ -121,6 +121,9 @@ struct ETCP_ROUTER_CONN {
     uint32_t sess_id;            // локальный счётчик переустановок (0 при создании, ++ при рестарте; на wire не пишется)
     uint8_t  start_sent;         // 0 = нужно отправить START в первом data
     uint8_t  peer_sync_done;     // 0 = rx_seq ещё не синхронизирован с удалённым seq (авто-создание/рестарт)
+    uint8_t* last_start_dgram;   // копия wire-пакета последнего принятого START (дедуп ретрансмитов)
+    size_t   last_start_dgram_len;
+    uint8_t  send_restart_pending; // 1 = RST принят и отправка переинициализирована (игнор повторных RST до первого ACK)
 
     // Ретрансмиты: inflight очередь
     struct ll_queue* inflight_q;        // хеш по seq (4 байта), непрерывный блок без SACK
diff --git a/tests/test_etcp_router_unit.c b/tests/test_etcp_router_unit.c
index 25413fe6..633beb01 100644
--- a/tests/test_etcp_router_unit.c
+++ b/tests/test_etcp_router_unit.c
@@ -672,7 +672,7 @@ static int pump_data(etcp_recv_fn recv_cb, struct UTUN_INSTANCE* inst,
 // ======================== Restart/session tests ========================
 
 static int test_rst_flag(void) {
-    TEST("RST flag — local state reset, service notified");
+    TEST("RST flag — send-side restart, no service notify");
     struct UASYNC* ua; struct UTUN_INSTANCE inst; etcp_recv_fn recv_cb;
     SETUP();
     g_notify_count = 0;
@@ -684,11 +684,13 @@ static int test_rst_flag(void) {
 
     g_notify_count = 0;
     inject(recv_cb, &inst, TEST_REMOTE_NODE, TEST_SVC_ID, 0, NULL, 0, 1, ROUTER_FLAG_RST);
-    if (g_notify_count != 1) FAIL("RST should notify service");
+    if (g_notify_count != 0) FAIL("RST should NOT notify service");
 
     struct ETCP_ROUTER_CONN* c = etcp_router_conn_get(&inst, TOPO_GROUP_UTUN, TEST_REMOTE_NODE, TEST_SVC_ID);
     if (!c) FAIL("rconn should still exist after reset");
-    if (c->tx_seq != 0 || c->rx_seq != 0 || c->start_sent != 0) FAIL("rconn not reset by RST");
+    if (c->tx_seq != 0 || c->start_sent != 0) FAIL("send side not reset by RST");
+    if (c->rx_seq != (uint32_t)n) FAIL("rx side should be untouched by RST");
+    if (!c->send_restart_pending) FAIL("send_restart_pending not set by RST");
     etcp_router_conn_close(c);
 
     TEARDOWN();
@@ -696,6 +698,29 @@ static int test_rst_flag(void) {
     return 0;
 }
 
+static int test_start_retransmit_no_restart(void) {
+    TEST("START retransmit (same payload) — no restart");
+    struct UASYNC* ua; struct UTUN_INSTANCE inst; etcp_recv_fn recv_cb;
+    SETUP();
+    g_notify_count = 0;
+
+    int n = rand() % 10 + 1;
+    rx_reset(0xC1);
+    pump_data(recv_cb, &inst, 0xC1, n, 0);
+    if (rx.delivered != n) FAIL("initial pump failed");
+
+    g_notify_count = 0;
+    // ретрансмит первого пакета (seq=0, START, тот же payload) — не должен рестартовать
+    uint8_t data[] = { TEST_SVC_ID, 0xC1, 0 };
+    inject(recv_cb, &inst, TEST_REMOTE_NODE, TEST_SVC_ID, 0, data + 1, 2, 0, ROUTER_FLAG_START);
+    if (g_notify_count != 0) FAIL("START retransmit should NOT restart");
+    if (rx.delivered != n) FAIL("duplicate START should not deliver");
+
+    TEARDOWN();
+    PASS();
+    return 0;
+}
+
 static int test_client_restart(void) {
     TEST("client restart — START flag detected after random data");
     struct UASYNC* ua; struct UTUN_INSTANCE inst; etcp_recv_fn recv_cb;
@@ -1157,6 +1182,7 @@ int main(void) {
     test_timestamp();
     test_conn_send_no_bgp();
     test_rst_flag();
+    test_start_retransmit_no_restart();
     test_client_restart();
     test_sess_id_increment();
     test_server_reinit();