diff --git a/trunk/configure b/trunk/configure
index 47aaa79d9..44a16d531 100755
--- a/trunk/configure
+++ b/trunk/configure
@@ -121,7 +121,7 @@ fi
 #####################################################################################
 # Modules, compile each module, then link to binary
 #
-#Core Module
+#Core, depends only on system apis.
 MODULE_ID="CORE" 
 MODULE_DEPENDS=() 
 ModuleLibIncs=(${SRS_OBJS})
@@ -129,12 +129,20 @@ MODULE_FILES=("srs_core" "srs_core_autofree")
 MODULE_DIR="src/core" . auto/modules.sh
 CORE_OBJS="${MODULE_OBJS[@]}"
 #
+#Kernel, depends on core, provides error/log/config, nothing about stream information.
+MODULE_ID="KERNEL" 
+MODULE_DEPENDS=("CORE") 
+ModuleLibIncs=(${SRS_OBJS})
+MODULE_FILES=("srs_kernel_error")
+MODULE_DIR="src/kernel" . auto/modules.sh
+KERNEL_OBJS="${MODULE_OBJS[@]}"
+#
 #App Module
 MODULE_ID="APP" 
-MODULE_DEPENDS=("CORE") 
+MODULE_DEPENDS=("CORE" "KERNEL") 
 ModuleLibIncs=(${LibSTRoot} ${LibHttpParserRoot} ${LibSSLRoot} ${SRS_OBJS})
 MODULE_FILES=("srs_core_log" "srs_core_server" 
-        "srs_core_error" "srs_core_conn" "srs_core_client" 
+         "srs_core_conn" "srs_core_client" 
         "srs_core_rtmp" "srs_core_socket" "srs_core_buffer"
         "srs_core_protocol" "srs_core_amf0"
         "srs_core_stream" "srs_core_source" "srs_core_codec"
@@ -148,7 +156,7 @@ APP_OBJS="${MODULE_OBJS[@]}"
 #
 #Main Module
 MODULE_ID="MAIN" 
-MODULE_DEPENDS=("CORE" "APP")
+MODULE_DEPENDS=("CORE" "KERNEL" "APP")
 ModuleLibIncs=(${LibSTRoot} ${SRS_OBJS})
 MODULE_FILES=("srs_main_server" "srs_main_bandcheck")
 MODULE_DIR="src/main" . auto/modules.sh
@@ -164,7 +172,7 @@ MAIN_ENTRANCES=("srs_main_server" "srs_main_bandcheck")
 # all depends libraries
 ModuleLibFiles=(${LibSTfile} ${LibHttpParserfile} ${LibSSLfile})
 # all depends objects
-MODULE_OBJS="${CORE_OBJS[@]} ${APP_OBJS[@]} ${MAIN_OBJS[@]}"
+MODULE_OBJS="${CORE_OBJS[@]} ${KERNEL_OBJS[@]} ${APP_OBJS[@]} ${MAIN_OBJS[@]}"
 LINK_OPTIONS="-ldl"
 #
 # srs:
diff --git a/trunk/src/app/srs_core_amf0.cpp b/trunk/src/app/srs_core_amf0.cpp
index 940bf6f1e..814519a9d 100644
--- a/trunk/src/app/srs_core_amf0.cpp
+++ b/trunk/src/app/srs_core_amf0.cpp
@@ -26,7 +26,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <utility>
 
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_stream.hpp>
 
 // AMF0 marker
diff --git a/trunk/src/app/srs_core_bandwidth.cpp b/trunk/src/app/srs_core_bandwidth.cpp
index fd833bd11..3ec565a94 100644
--- a/trunk/src/app/srs_core_bandwidth.cpp
+++ b/trunk/src/app/srs_core_bandwidth.cpp
@@ -29,7 +29,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 using namespace std;
 
 #include <srs_core_rtmp.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_amf0.hpp>
 #include <srs_core_protocol.hpp>
 #include <srs_core_config.hpp>
diff --git a/trunk/src/app/srs_core_buffer.cpp b/trunk/src/app/srs_core_buffer.cpp
index 31572b6c5..b5f23ff4d 100644
--- a/trunk/src/app/srs_core_buffer.cpp
+++ b/trunk/src/app/srs_core_buffer.cpp
@@ -23,7 +23,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_buffer.hpp>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_socket.hpp>
 #include <srs_core_log.hpp>
 
diff --git a/trunk/src/app/srs_core_client.cpp b/trunk/src/app/srs_core_client.cpp
index 78f7c05c9..9fb104ab5 100644
--- a/trunk/src/app/srs_core_client.cpp
+++ b/trunk/src/app/srs_core_client.cpp
@@ -28,7 +28,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 using namespace std;
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_rtmp.hpp>
 #include <srs_core_protocol.hpp>
diff --git a/trunk/src/app/srs_core_codec.cpp b/trunk/src/app/srs_core_codec.cpp
index 323d7621e..60fc8ee29 100644
--- a/trunk/src/app/srs_core_codec.cpp
+++ b/trunk/src/app/srs_core_codec.cpp
@@ -26,7 +26,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <string.h>
 #include <stdlib.h>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_stream.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_autofree.hpp>
diff --git a/trunk/src/app/srs_core_config.cpp b/trunk/src/app/srs_core_config.cpp
index 812bb7062..1cb34b915 100644
--- a/trunk/src/app/srs_core_config.cpp
+++ b/trunk/src/app/srs_core_config.cpp
@@ -37,7 +37,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <algorithm>
 using namespace std;
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_autofree.hpp>
 
diff --git a/trunk/src/app/srs_core_conn.cpp b/trunk/src/app/srs_core_conn.cpp
index 02c758891..fad20a0be 100644
--- a/trunk/src/app/srs_core_conn.cpp
+++ b/trunk/src/app/srs_core_conn.cpp
@@ -24,7 +24,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_core_conn.hpp>
 
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_server.hpp>
 
 SrsConnection::SrsConnection(SrsServer* srs_server, st_netfd_t client_stfd)
diff --git a/trunk/src/app/srs_core_encoder.cpp b/trunk/src/app/srs_core_encoder.cpp
index 95cf523ac..082d7eeeb 100644
--- a/trunk/src/app/srs_core_encoder.cpp
+++ b/trunk/src/app/srs_core_encoder.cpp
@@ -32,7 +32,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <algorithm>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_config.hpp>
 #include <srs_core_rtmp.hpp>
diff --git a/trunk/src/app/srs_core_forward.cpp b/trunk/src/app/srs_core_forward.cpp
index 98c545399..75830e75d 100644
--- a/trunk/src/app/srs_core_forward.cpp
+++ b/trunk/src/app/srs_core_forward.cpp
@@ -28,7 +28,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_rtmp.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_protocol.hpp>
diff --git a/trunk/src/app/srs_core_handshake.cpp b/trunk/src/app/srs_core_handshake.cpp
index 32239ee03..a014d0ddb 100644
--- a/trunk/src/app/srs_core_handshake.cpp
+++ b/trunk/src/app/srs_core_handshake.cpp
@@ -26,7 +26,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <time.h>
 #include <stdlib.h>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_autofree.hpp>
 #include <srs_core_socket.hpp>
diff --git a/trunk/src/app/srs_core_hls.cpp b/trunk/src/app/srs_core_hls.cpp
index 8d0b14d81..d9f5f6a84 100644
--- a/trunk/src/app/srs_core_hls.cpp
+++ b/trunk/src/app/srs_core_hls.cpp
@@ -33,7 +33,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <algorithm>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_codec.hpp>
 #include <srs_core_amf0.hpp>
 #include <srs_core_protocol.hpp>
diff --git a/trunk/src/app/srs_core_http.cpp b/trunk/src/app/srs_core_http.cpp
index 9f350e493..e9231cafb 100644
--- a/trunk/src/app/srs_core_http.cpp
+++ b/trunk/src/app/srs_core_http.cpp
@@ -32,7 +32,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_rtmp.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_socket.hpp>
diff --git a/trunk/src/app/srs_core_pithy_print.cpp b/trunk/src/app/srs_core_pithy_print.cpp
index e375c4006..265071ac4 100644
--- a/trunk/src/app/srs_core_pithy_print.cpp
+++ b/trunk/src/app/srs_core_pithy_print.cpp
@@ -29,7 +29,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_core_log.hpp>
 #include <srs_core_config.hpp>
 #include <srs_core_reload.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 
 #define SRS_STAGE_DEFAULT_INTERVAL_MS 1200
 
diff --git a/trunk/src/app/srs_core_protocol.cpp b/trunk/src/app/srs_core_protocol.cpp
index a5ddfa61e..56727c962 100644
--- a/trunk/src/app/srs_core_protocol.cpp
+++ b/trunk/src/app/srs_core_protocol.cpp
@@ -25,7 +25,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_log.hpp>
 #include <srs_core_amf0.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_socket.hpp>
 #include <srs_core_buffer.hpp>
 #include <srs_core_stream.hpp>
diff --git a/trunk/src/app/srs_core_protocol.hpp b/trunk/src/app/srs_core_protocol.hpp
index cc79f10f2..003b31c11 100644
--- a/trunk/src/app/srs_core_protocol.hpp
+++ b/trunk/src/app/srs_core_protocol.hpp
@@ -35,7 +35,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_st.hpp>
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 
 // the following is the timeout for rtmp protocol, 
 // to avoid death connection.
diff --git a/trunk/src/app/srs_core_refer.cpp b/trunk/src/app/srs_core_refer.cpp
index c7ff7ac1a..b04572964 100644
--- a/trunk/src/app/srs_core_refer.cpp
+++ b/trunk/src/app/srs_core_refer.cpp
@@ -23,7 +23,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_refer.hpp>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_log.hpp>
 #include <srs_core_config.hpp>
 
diff --git a/trunk/src/app/srs_core_reload.cpp b/trunk/src/app/srs_core_reload.cpp
index d4cd85f58..e2da1f2bb 100644
--- a/trunk/src/app/srs_core_reload.cpp
+++ b/trunk/src/app/srs_core_reload.cpp
@@ -25,7 +25,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 using namespace std;
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 
 ISrsReloadHandler::ISrsReloadHandler()
 {
diff --git a/trunk/src/app/srs_core_rtmp.cpp b/trunk/src/app/srs_core_rtmp.cpp
index 14df9c25d..06340450a 100644
--- a/trunk/src/app/srs_core_rtmp.cpp
+++ b/trunk/src/app/srs_core_rtmp.cpp
@@ -24,7 +24,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_core_rtmp.hpp>
 
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_socket.hpp>
 #include <srs_core_protocol.hpp>
 #include <srs_core_autofree.hpp>
diff --git a/trunk/src/app/srs_core_server.cpp b/trunk/src/app/srs_core_server.cpp
index a10e6da80..2beb1060a 100644
--- a/trunk/src/app/srs_core_server.cpp
+++ b/trunk/src/app/srs_core_server.cpp
@@ -31,7 +31,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <algorithm>
 
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_client.hpp>
 #include <srs_core_config.hpp>
 
diff --git a/trunk/src/app/srs_core_socket.cpp b/trunk/src/app/srs_core_socket.cpp
index 7628c3c70..90ec123db 100644
--- a/trunk/src/app/srs_core_socket.cpp
+++ b/trunk/src/app/srs_core_socket.cpp
@@ -23,7 +23,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_socket.hpp>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 
 SrsSocket::SrsSocket(st_netfd_t client_stfd)
 {
diff --git a/trunk/src/app/srs_core_stream.cpp b/trunk/src/app/srs_core_stream.cpp
index a22581c07..7baaa901c 100644
--- a/trunk/src/app/srs_core_stream.cpp
+++ b/trunk/src/app/srs_core_stream.cpp
@@ -24,7 +24,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #include <srs_core_stream.hpp>
 
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 
 SrsStream::SrsStream()
 {
diff --git a/trunk/src/app/srs_core_thread.cpp b/trunk/src/app/srs_core_thread.cpp
index b6742f29c..ee3626b8a 100644
--- a/trunk/src/app/srs_core_thread.cpp
+++ b/trunk/src/app/srs_core_thread.cpp
@@ -23,7 +23,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_thread.hpp>
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_log.hpp>
 
 ISrsThreadHandler::ISrsThreadHandler()
diff --git a/trunk/src/app/srs_core_error.cpp b/trunk/src/kernel/srs_kernel_error.cpp
similarity index 97%
rename from trunk/src/app/srs_core_error.cpp
rename to trunk/src/kernel/srs_kernel_error.cpp
index 226a61027..db333e2ea 100644
--- a/trunk/src/app/srs_core_error.cpp
+++ b/trunk/src/kernel/srs_kernel_error.cpp
@@ -21,7 +21,7 @@ IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 
 bool srs_is_system_control_error(int error_code)
 {
diff --git a/trunk/src/app/srs_core_error.hpp b/trunk/src/kernel/srs_kernel_error.hpp
similarity index 98%
rename from trunk/src/app/srs_core_error.hpp
rename to trunk/src/kernel/srs_kernel_error.hpp
index e08564776..e8c424f06 100644
--- a/trunk/src/app/srs_core_error.hpp
+++ b/trunk/src/kernel/srs_kernel_error.hpp
@@ -21,11 +21,11 @@ IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 
-#ifndef SRS_CORE_ERROR_HPP
-#define SRS_CORE_ERROR_HPP
+#ifndef SRS_KERNEL_ERROR_HPP
+#define SRS_KERNEL_ERROR_HPP
 
 /*
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 */
 
 #include <srs_core.hpp>
diff --git a/trunk/src/main/srs_main_bandcheck.cpp b/trunk/src/main/srs_main_bandcheck.cpp
index 107722d1c..6f28ede19 100644
--- a/trunk/src/main/srs_main_bandcheck.cpp
+++ b/trunk/src/main/srs_main_bandcheck.cpp
@@ -30,7 +30,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core_rtmp.hpp>
 #include <srs_core_protocol.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_amf0.hpp>
 #include <srs_core_autofree.hpp>
 #include <srs_core_stream.hpp>
diff --git a/trunk/src/main/srs_main_server.cpp b/trunk/src/main/srs_main_server.cpp
index e87527e36..6d98cc840 100644
--- a/trunk/src/main/srs_main_server.cpp
+++ b/trunk/src/main/srs_main_server.cpp
@@ -22,7 +22,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 
 #include <srs_core_log.hpp>
-#include <srs_core_error.hpp>
+#include <srs_kernel_error.hpp>
 #include <srs_core_server.hpp>
 #include <srs_core_config.hpp>
 
diff --git a/trunk/src/srs/srs.upp b/trunk/src/srs/srs.upp
index d819d9424..bbe313879 100755
--- a/trunk/src/srs/srs.upp
+++ b/trunk/src/srs/srs.upp
@@ -9,6 +9,9 @@ file
     ..\core\srs_core.cpp,
     ..\core\srs_core_autofree.hpp,
     ..\core\srs_core_autofree.cpp,
+    kernel readonly separator,
+    ..\kernel\srs_kernel_error.hpp,
+    ..\kernel\srs_kernel_error.cpp,
     app readonly separator,
     ..\app\srs_core_amf0.hpp,
     ..\app\srs_core_amf0.cpp,
@@ -26,8 +29,6 @@ file
     ..\app\srs_core_conn.cpp,
     ..\app\srs_core_encoder.hpp,
     ..\app\srs_core_encoder.cpp,
-    ..\app\srs_core_error.hpp,
-    ..\app\srs_core_error.cpp,
     ..\app\srs_core_forward.hpp,
     ..\app\srs_core_forward.cpp,
     ..\app\srs_core_handshake.hpp,