diff --git a/net/Makefile.objs b/net/Makefile.objs
index 914aec0..5fa2f97 100644
--- a/net/Makefile.objs
+++ b/net/Makefile.objs
@@ -14,3 +14,4 @@ common-obj-$(CONFIG_SLIRP) += slirp.o
 common-obj-$(CONFIG_VDE) += vde.o
 common-obj-$(CONFIG_NETMAP) += netmap.o
 common-obj-y += filter.o
+common-obj-y += filter-buffer.o
diff --git a/net/filter-buffer.c b/net/filter-buffer.c
new file mode 100644
index 0000000..1547765
--- /dev/null
+++ b/net/filter-buffer.c
@@ -0,0 +1,162 @@
+/*
+ * Copyright (c) 2015 FUJITSU LIMITED
+ * Author: Yang Hongyang <yanghy@cn.fujitsu.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#include "net/filter.h"
+#include "net/queue.h"
+#include "filters.h"
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "qemu/main-loop.h"
+#include "qemu/timer.h"
+#include "qemu/iov.h"
+
+typedef struct FILTERBUFFERState {
+    NetFilterState nf;
+    NetQueue *incoming_queue;
+    NetQueue *inflight_queue;
+    QEMUBH *flush_bh;
+    int64_t interval;
+    QEMUTimer release_timer;
+} FILTERBUFFERState;
+
+static void packet_send_completed(NetClientState *nc, ssize_t len)
+{
+    return;
+}
+
+static void filter_buffer_flush(NetFilterState *nf)
+{
+    FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf);
+    NetQueue *queue = s->inflight_queue;
+    NetPacket *packet;
+
+    while (queue && !QTAILQ_EMPTY(&queue->packets)) {
+        packet = QTAILQ_FIRST(&queue->packets);
+        QTAILQ_REMOVE(&queue->packets, packet, entry);
+        queue->nq_count--;
+
+        if (packet->sender && packet->sender->peer) {
+            qemu_net_queue_send(packet->sender->peer->incoming_queue,
+                                packet->sender,
+                                packet->flags,
+                                packet->data,
+                                packet->size,
+                                packet->sent_cb);
+        }
+
+        /*
+         * now that we pass the packet to sender->peer->incoming_queue, we
+         * don't care the reture value here, because the peer's queue will
+         * take care of this packet
+         */
+        g_free(packet);
+    }
+
+    g_free(queue);
+    s->inflight_queue = NULL;
+}
+
+static void filter_buffer_flush_bh(void *opaque)
+{
+    FILTERBUFFERState *s = opaque;
+    NetFilterState *nf = &s->nf;
+    filter_buffer_flush(nf);
+}
+
+static void filter_buffer_release_one(NetFilterState *nf)
+{
+    FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf);
+
+    /* flush inflight packets */
+    if (s->inflight_queue) {
+        filter_buffer_flush(nf);
+    }
+
+    s->inflight_queue = s->incoming_queue;
+    s->incoming_queue = qemu_new_net_queue(nf);
+    qemu_bh_schedule(s->flush_bh);
+}
+
+static void filter_buffer_release_timer(void *opaque)
+{
+    FILTERBUFFERState *s = opaque;
+    filter_buffer_release_one(&s->nf);
+    timer_mod(&s->release_timer,
+              qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval);
+}
+
+/* filter APIs */
+static ssize_t filter_buffer_receive_iov(NetFilterState *nf,
+                                         NetClientState *sender,
+                                         unsigned flags,
+                                         const struct iovec *iov,
+                                         int iovcnt)
+{
+    FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf);
+    NetQueue *queue = s->incoming_queue;
+
+    qemu_net_queue_append_iov(queue, sender, flags, iov, iovcnt,
+                              packet_send_completed);
+    return iov_size(iov, iovcnt);
+}
+
+static void filter_buffer_cleanup(NetFilterState *nf)
+{
+    FILTERBUFFERState *s = DO_UPCAST(FILTERBUFFERState, nf, nf);
+
+    if (s->interval) {
+        timer_del(&s->release_timer);
+    }
+
+    /* flush inflight packets */
+    filter_buffer_flush(nf);
+    /* flush incoming packets */
+    s->inflight_queue = s->incoming_queue;
+    s->incoming_queue = NULL;
+    filter_buffer_flush(nf);
+
+    if (s->flush_bh) {
+        qemu_bh_delete(s->flush_bh);
+        s->flush_bh = NULL;
+    }
+    return;
+}
+
+
+static NetFilterInfo net_filter_buffer_info = {
+    .type = NET_FILTER_OPTIONS_KIND_BUFFER,
+    .size = sizeof(FILTERBUFFERState),
+    .receive_iov = filter_buffer_receive_iov,
+    .cleanup = filter_buffer_cleanup,
+};
+
+int net_init_filter_buffer(const NetFilterOptions *opts, const char *name,
+                           int chain, NetClientState *netdev, Error **errp)
+{
+    NetFilterState *nf;
+    FILTERBUFFERState *s;
+    const NetFilterBufferOptions *bufferopt;
+
+    assert(opts->kind == NET_FILTER_OPTIONS_KIND_BUFFER);
+    bufferopt = opts->buffer;
+
+    nf = qemu_new_net_filter(&net_filter_buffer_info,
+                             netdev, "buffer", name, chain);
+    s = DO_UPCAST(FILTERBUFFERState, nf, nf);
+    s->incoming_queue = qemu_new_net_queue(nf);
+    s->flush_bh = qemu_bh_new(filter_buffer_flush_bh, s);
+    s->interval = bufferopt->has_interval ? bufferopt->interval : 0;
+    if (s->interval) {
+        timer_init_us(&s->release_timer, QEMU_CLOCK_VIRTUAL,
+                      filter_buffer_release_timer, s);
+        timer_mod(&s->release_timer,
+                  qemu_clock_get_us(QEMU_CLOCK_VIRTUAL) + s->interval);
+    }
+
+    return 0;
+}
diff --git a/net/filter.c b/net/filter.c
index 84845b1..ba78683 100644
--- a/net/filter.c
+++ b/net/filter.c
@@ -17,6 +17,7 @@
 
 #include "net/filter.h"
 #include "net/net.h"
+#include "filters.h"
 
 static QTAILQ_HEAD(, NetFilterState) net_filters;
 
@@ -168,6 +169,7 @@ typedef int (NetFilterInit)(const NetFilterOptions *opts,
 
 static
 NetFilterInit * const net_filter_init_fun[NET_FILTER_OPTIONS_KIND_MAX] = {
+    [NET_FILTER_OPTIONS_KIND_BUFFER] = net_init_filter_buffer,
 };
 
 static int net_filter_init1(const NetFilter *netfilter, Error **errp)
diff --git a/net/filters.h b/net/filters.h
new file mode 100644
index 0000000..3b546db
--- /dev/null
+++ b/net/filters.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2015 FUJITSU LIMITED
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_NET_FILTERS_H
+#define QEMU_NET_FILTERS_H
+
+#include "net/net.h"
+#include "net/filter.h"
+
+int net_init_filter_buffer(const NetFilterOptions *opts, const char *name,
+                           int chain, NetClientState *netdev, Error **errp);
+
+#endif /* QEMU_NET_FILTERS_H */
diff --git a/qapi-schema.json b/qapi-schema.json
index 9d97c21..e51bb59 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2584,6 +2584,21 @@
 { 'command': 'netfilter_del', 'data': {'id': 'str'} }
 
 ##
+# @NetFilterBufferOptions
+#
+# a netbuffer filter for network backend.
+#
+# @interval: #optional release packets by interval, if no interval supplied,
+#            will release packets when filter_buffer_release_all been called.
+#            scale: microsecond
+#
+# Since 2.5
+##
+{ 'struct': 'NetFilterBufferOptions',
+  'data': {
+    '*interval':     'int64' } }
+
+##
 # @NetFilterOptions
 #
 # A discriminated record of network filters.
@@ -2592,7 +2607,8 @@
 #
 ##
 { 'union': 'NetFilterOptions',
-  'data': { } }
+  'data': {
+    'buffer':     'NetFilterBufferOptions'} }
 
 ##
 # @NetFilter
