diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c
index 5a1e84f..a1cdc76 100644
--- a/src/vnet/tcp/tcp_input.c
+++ b/src/vnet/tcp/tcp_input.c
@@ -941,6 +941,7 @@
 {
   tcp_fastrecovery_on (tc);
   tc->snd_congestion = tc->snd_una_max;
+  tc->cwnd_acc_bytes = 0;
   tc->cc_algo->congestion (tc);
   TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 4);
 }