diff --git a/README.md b/README.md
index 2b324878b..dd89c5705 100755
--- a/README.md
+++ b/README.md
@@ -205,6 +205,7 @@ Please select your language:
 
 ### V2 changes
 
+* v2.0, 2017-01-11, fix [#588][bug #588], kbps interface error. 2.0.228
 * v2.0, 2017-01-11, fix [#736][bug #736], recovery the hls dispose. 2.0.227
 * v2.0, 2017-01-10, refine hls html5 video template.
 * v2.0, 2017-01-10, fix [#635][bug #635], hls support NonIDR(open gop). 2.0.226
@@ -1368,6 +1369,9 @@ Winlin
 [bug #513]: https://github.com/ossrs/srs/issues/513
 [bug #730]: https://github.com/ossrs/srs/issues/730
 [bug #635]: https://github.com/ossrs/srs/issues/635
+[bug #736]: https://github.com/ossrs/srs/issues/736
+[bug #588]: https://github.com/ossrs/srs/issues/588
+[bug #xxxxxxxxxx]: https://github.com/ossrs/srs/issues/xxxxxxxxxx
 [bug #735]: https://github.com/ossrs/srs/issues/735
 [bug #xxxxxxxxxx]: https://github.com/ossrs/srs/issues/xxxxxxxxxx
 
diff --git a/trunk/src/protocol/srs_protocol_kbps.cpp b/trunk/src/protocol/srs_protocol_kbps.cpp
index 01671f699..4693430de 100644
--- a/trunk/src/protocol/srs_protocol_kbps.cpp
+++ b/trunk/src/protocol/srs_protocol_kbps.cpp
@@ -120,7 +120,7 @@ void SrsKbps::set_io(ISrsProtocolStatistic* in, ISrsProtocolStatistic* out)
     }
     // save the old in bytes.
     if (is.io.in) {
-        is.bytes += is.last_bytes - is.io_bytes_base;
+        is.bytes += is.io.in->get_recv_bytes() - is.io_bytes_base;
     }
     // use new io.
     is.io.in = in;
@@ -138,7 +138,7 @@ void SrsKbps::set_io(ISrsProtocolStatistic* in, ISrsProtocolStatistic* out)
     }
     // save the old in bytes.
     if (os.io.out) {
-        os.bytes += os.last_bytes - os.io_bytes_base;
+        os.bytes += os.io.out->get_send_bytes() - os.io_bytes_base;
     }
     // use new io.
     os.io.out = out;
@@ -192,12 +192,46 @@ int SrsKbps::get_recv_kbps_5m()
 
 int64_t SrsKbps::get_send_bytes()
 {
-    return os.get_total_bytes();
+    // we must calc the send bytes dynamically,
+    // to not depends on the sample(which used to calc the kbps).
+    // @read https://github.com/ossrs/srs/issues/588
+    
+    // session start bytes.
+    int64_t bytes = os.bytes;
+    
+    // When exists active session, use it to get the last bytes.
+    if (os.io.out) {
+        bytes += os.io.out->get_send_bytes() - os.io_bytes_base;
+        return bytes;
+    }
+    
+    // When no active session, the last_bytes record the last valid bytes.
+    // TODO: Maybe the bellow bytes is zero, because the ios.io.out is NULL.
+    bytes += os.last_bytes - os.io_bytes_base;
+
+    return bytes;
 }
 
 int64_t SrsKbps::get_recv_bytes()
 {
-    return is.get_total_bytes();
+    // we must calc the send bytes dynamically,
+    // to not depends on the sample(which used to calc the kbps).
+    // @read https://github.com/ossrs/srs/issues/588
+    
+    // session start bytes.
+    int64_t bytes = is.bytes;
+    
+    // When exists active session, use it to get the last bytes.
+    if (is.io.in) {
+        bytes += is.io.in->get_recv_bytes() - is.io_bytes_base;
+        return bytes;
+    }
+    
+    // When no active session, the last_bytes record the last valid bytes.
+    // TODO: Maybe the bellow bytes is zero, because the ios.io.out is NULL.
+    bytes += is.last_bytes - is.io_bytes_base;
+
+    return bytes;
 }
 
 void SrsKbps::resample()
@@ -250,3 +284,8 @@ void SrsKbps::sample()
     os.sample();
 }
 
+int SrsKbps::size_memory()
+{
+    return sizeof(SrsKbps);
+}
+
diff --git a/trunk/src/protocol/srs_protocol_kbps.hpp b/trunk/src/protocol/srs_protocol_kbps.hpp
index c4b2b88e2..ff6f0cec0 100644
--- a/trunk/src/protocol/srs_protocol_kbps.hpp
+++ b/trunk/src/protocol/srs_protocol_kbps.hpp
@@ -95,13 +95,9 @@ public:
     SrsKbpsSlice();
     virtual ~SrsKbpsSlice();
 public:
-    /**
-    * get current total bytes.
-    */
+    // Get current total bytes, not depend on sample().
     virtual int64_t get_total_bytes();
-    /**
-    * resample all samples.
-    */
+    // Resample the slice to calculate the kbps.
     virtual void sample();
 };
 
@@ -161,6 +157,13 @@ public:
  *      delta->resample();
  *      printf("delta is %d/%d", delta->get_send_bytes_delta(), delta->get_recv_bytes_delta());
  *      delta->cleanup();
+ * 4. kbps used as ISrsProtocolStatistic, to provides raw bytes:
+ *      SrsKbps* kbps = ...;
+ *      kbps->set_io(in, out);
+ *      // both kbps->get_recv_bytes() and kbps->get_send_bytes() are available.
+*       // we can use the kbps as the data source of another kbps:
+ *      SrsKbps* user = ...;
+ *      user->set_io(kbps, kbps);
  *   the server never know how many bytes already send/recv, for the connection maybe closed.
  */
 class SrsKbps : public virtual ISrsProtocolStatistic, public virtual IKbpsDelta
@@ -195,26 +198,15 @@ public:
     // 5m
     virtual int get_send_kbps_5m();
     virtual int get_recv_kbps_5m();
+// interface ISrsProtocolStatistic
 public:
-    /**
-    * get the total send/recv bytes, from the startup of the oldest io.
-    * @remark, use sample() to update data.
-    */
     virtual int64_t get_send_bytes();
     virtual int64_t get_recv_bytes();
+// interface IKbpsDelta
 public:
-    /**
-    * resample to get the delta.
-    */
     virtual void resample();
-    /**
-    * get the delta of send/recv bytes.
-    */
     virtual int64_t get_send_bytes_delta();
     virtual int64_t get_recv_bytes_delta();
-    /**
-    * cleanup the delta.
-    */
     virtual void cleanup();
 public:
     /**
@@ -232,6 +224,9 @@ public:
     *       use the add_delta() is better solutions.
     */
     virtual void sample();
+// interface ISrsMemorySizer
+public:
+    virtual int size_memory();
 };
 
 #endif