diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 457ffff..c2629f5 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -133,6 +133,4 @@ jobs:
           releases/server_windows_arm.zip
           releases/server_windows_arm64.zip
           releases/server_windows_i386.zip
-          releases/server_windows_amd64.zip
-      env:
-        GITHUB_REPOSITORY: XZB-1248/Spark
\ No newline at end of file
+          releases/server_windows_amd64.zip
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..cb56461
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,23 @@
+## v0.0.3
+
+* Add: network IO speed monitoring.
+* Add: support client self-upgrade.
+* Fix: garbled characters when display Chinese on Unix-like OS.
+* BREAKING-CHANGE: module `Device` has changed.
+* THIS RELEASE IS **NOT** COMPATIBLE WITH LAST RELEASE.
+
+
+
+## v0.0.2
+
+* Add: latency check.
+* Add: progress bar of cpu usage, memory usage and disk usage.
+* BREAKING-CHANGE: module `Device` has changed.
+* THIS RELEASE IS **NOT** COMPATIBLE WITH LAST RELEASE.
+
+
+
+## v0.0.1
+
+* First release.
+* 
\ No newline at end of file
diff --git a/LICENSE b/LICENSE
index 84d3e4a..4508590 100644
--- a/LICENSE
+++ b/LICENSE
@@ -23,3 +23,56 @@ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+-------
+
+utils/melody are copied and modified from olahol/melody.
+
+Copyright (c) 2015 Ola Holmström. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+-------
+
+utils/cmap are copied and modified from orcaman/concurrent-map.
+
+The MIT License (MIT)
+
+Copyright (c) 2014 streamrail
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER 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.
\ No newline at end of file
diff --git a/README.ZH.md b/README.ZH.md
index 16034af..d644b75 100644
--- a/README.ZH.md
+++ b/README.ZH.md
@@ -130,6 +130,46 @@ $ go build -ldflags "-s -w" -o Spark Spark/Server
 
 ---
 
+## 项目依赖
+
+Spark使用了许多第三方的开源项目。
+
+依赖列表可以在 `go.mod` 和 `package.json` 里面找到。
+
+一些主要的依赖项如下列所示。
+
+### 后端
+
+* [Go](https://github.com/golang/go) ([License](https://github.com/golang/go/blob/master/LICENSE))
+
+* [gin-gonic/gin](https://github.com/gin-gonic/gin) (MIT License)
+
+* [imroc/req](https://github.com/imroc/req) (MIT License)
+
+* [kbinani/screenshot](https://github.com/kbinani/screenshot) (MIT License)
+
+* [shirou/gopsutil](https://github.com/shirou/gopsutil) ([License](https://github.com/shirou/gopsutil/blob/master/LICENSE))
+
+* [gorilla/websocket](https://github.com/gorilla/websocket) (BSD-2-Clause License)
+
+* [olahol/melody](https://github.com/olahol/melody) (BSD-2-Clause License)
+
+* [orcaman/concurrent-map](https://github.com/orcaman/concurrent-map) (MIT License)
+
+### 前端
+
+* [React](https://github.com/facebook/react) (MIT License)
+
+* [Ant-Design](https://github.com/ant-design/ant-design) (MIT License)
+
+* [axios](https://github.com/axios/axios) (MIT License)
+
+* [xterm.js](https://github.com/xtermjs/xterm.js) (MIT License)
+
+* [crypto-js](https://github.com/brix/crypto-js) (MIT License)
+
+---
+
 ## 开源协议
 
 本项目基于 [BSD-2 协议](./LICENSE) 。
\ No newline at end of file
diff --git a/README.md b/README.md
index 4e12d36..8e80fef 100644
--- a/README.md
+++ b/README.md
@@ -125,6 +125,44 @@ $ go build -ldflags "-s -w" -o Spark Spark/Server
 
 ---
 
+## Dependencies
+
+Spark contains many third-party open-source projects.
+
+Lists of dependencies can be found at `go.mod` and `package.json`.
+
+Some major dependencies are listed below.
+
+### Back-end
+
+* [Go](https://github.com/golang/go) ([License](https://github.com/golang/go/blob/master/LICENSE))
+
+* [gin-gonic/gin](https://github.com/gin-gonic/gin) (MIT License)
+
+* [imroc/req](https://github.com/imroc/req) (MIT License)
+
+* [kbinani/screenshot](https://github.com/kbinani/screenshot) (MIT License)
+
+* [shirou/gopsutil](https://github.com/shirou/gopsutil) ([License](https://github.com/shirou/gopsutil/blob/master/LICENSE))
+
+* [gorilla/websocket](https://github.com/gorilla/websocket) (BSD-2-Clause License)
+
+* [orcaman/concurrent-map](https://github.com/orcaman/concurrent-map) (MIT License)
+
+### Front-end
+
+* [React](https://github.com/facebook/react) (MIT License)
+
+* [Ant-Design](https://github.com/ant-design/ant-design) (MIT License)
+
+* [axios](https://github.com/axios/axios) (MIT License)
+
+* [xterm.js](https://github.com/xtermjs/xterm.js) (MIT License)
+
+* [crypto-js](https://github.com/brix/crypto-js) (MIT License)
+
+---
+
 ## License
 
 [BSD-2 License](./LICENSE)
\ No newline at end of file
diff --git a/build.client.bat b/build.client.bat
index 2c8ee1b..764b929 100644
--- a/build.client.bat
+++ b/build.client.bat
@@ -1,30 +1,32 @@
 set GO111MODULE=auto
 mkdir .\built
+for /F %%i in ('git rev-parse HEAD') do ( set COMMIT=%%i)
+
 
 
 set GOOS=linux
 
 set GOARCH=arm
-go build -ldflags "-s -w" -o ./built/linux_arm Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/linux_arm Spark/client
 set GOARCH=arm64
-go build -ldflags "-s -w" -o ./built/linux_arm64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/linux_arm64 Spark/client
 set GOARCH=386
-go build -ldflags "-s -w" -o ./built/linux_i386 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/linux_i386 Spark/client
 set GOARCH=amd64
-go build -ldflags "-s -w" -o ./built/linux_amd64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/linux_amd64 Spark/client
 
 
 
 set GOOS=windows
 
 set GOARCH=arm
-go build -ldflags "-s -w" -o ./built/windows_arm Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/windows_arm Spark/client
 set GOARCH=arm64
-go build -ldflags "-s -w" -o ./built/windows_arm64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/windows_arm64 Spark/client
 set GOARCH=386
-go build -ldflags "-s -w" -o ./built/windows_i386 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/windows_i386 Spark/client
 set GOARCH=amd64
-go build -ldflags "-s -w" -o ./built/windows_amd64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/windows_amd64 Spark/client
 
 
 
@@ -34,23 +36,19 @@ go build -ldflags "-s -w" -o ./built/windows_amd64 Spark/client
 @REM set GOARCH=arm
 @REM set CC=armv7a-linux-androideabi21-clang
 @REM set CXX=armv7a-linux-androideabi21-clang++
-@REM go build -ldflags "-s -w" -o ./built/android_armv7a Spark/client
+@REM go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/android_arm Spark/client
 
 @REM set GOARCH=arm64
 @REM set CC=aarch64-linux-android21-clang
 @REM set CXX=aarch64-linux-android21-clang++
-@REM go build -ldflags "-s -w" -o ./built/android_aarch64 Spark/client
+@REM go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/android_arm64 Spark/client
 
 @REM set GOARCH=386
 @REM set CC=i686-linux-android21-clang
 @REM set CXX=i686-linux-android21-clang++
-@REM go build -ldflags "-s -w" -o ./built/android_i686 Spark/client
+@REM go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/android_i386 Spark/client
 
 @REM set GOARCH=amd64
 @REM set CC=x86_64-linux-android21-clang
 @REM set CXX=x86_64-linux-android21-clang++
-@REM go build -ldflags "-s -w" -o ./built/android_x86_64 Spark/client
-
-
-
-statik -m -src="./built" -f -dest="./server/embed" -include=* -p built -ns built
\ No newline at end of file
+@REM go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=%COMMIT%'" -o ./built/android_amd64 Spark/client
diff --git a/build.client.sh b/build.client.sh
index 98a006c..e5fd5f1 100644
--- a/build.client.sh
+++ b/build.client.sh
@@ -1,30 +1,31 @@
 export GO111MODULE=auto
 mkdir ./built
+export COMMIT=`git rev-parse HEAD`
 
 
 export GOOS=linux
 
 export GOARCH=arm
-go build -ldflags "-s -w" -o ./built/linux_arm Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/linux_arm Spark/client
 export GOARCH=arm64
-go build -ldflags "-s -w" -o ./built/linux_arm64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/linux_arm64 Spark/client
 export GOARCH=386
-go build -ldflags "-s -w" -o ./built/linux_i386 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/linux_i386 Spark/client
 export GOARCH=amd64
-go build -ldflags "-s -w" -o ./built/linux_amd64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/linux_amd64 Spark/client
 
 
 
 export GOOS=windows
 
 export GOARCH=arm
-go build -ldflags "-s -w" -o ./built/windows_arm Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/windows_arm Spark/client
 export GOARCH=arm64
-go build -ldflags "-s -w" -o ./built/windows_arm64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/windows_arm64 Spark/client
 export GOARCH=386
-go build -ldflags "-s -w" -o ./built/windows_i386 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/windows_i386 Spark/client
 export GOARCH=amd64
-go build -ldflags "-s -w" -o ./built/windows_amd64 Spark/client
+go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/windows_amd64 Spark/client
 
 
 
@@ -34,23 +35,19 @@ go build -ldflags "-s -w" -o ./built/windows_amd64 Spark/client
 # export GOARCH=arm
 # export CC=armv7a-linux-androideabi21-clang
 # export CXX=armv7a-linux-androideabi21-clang++
-# go build -ldflags "-s -w" -o ./built/android_armv7a Spark/client
+# go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/android_arm Spark/client
 
 # export GOARCH=arm64
 # export CC=aarch64-linux-android21-clang
 # export CXX=aarch64-linux-android21-clang++
-# go build -ldflags "-s -w" -o ./built/android_aarch64 Spark/client
+# go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/android_arm64 Spark/client
 
 # export GOARCH=386
 # export CC=i686-linux-android21-clang
 # export CXX=i686-linux-android21-clang++
-# go build -ldflags "-s -w" -o ./built/android_i686 Spark/client
+# go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/android_i386 Spark/client
 
 # export GOARCH=amd64
 # export CC=x86_64-linux-android21-clang
 # export CXX=x86_64-linux-android21-clang++
-# go build -ldflags "-s -w" -o ./built/android_x86_64 Spark/client
-
-
-
-statik -m -src="./built" -f -dest="./server/embed" -include=* -p built -ns built
\ No newline at end of file
+# go build -ldflags "-s -w -X 'Spark/client/config.COMMIT=$COMMIT'" -o ./built/android_amd64 Spark/client
diff --git a/build.server.sh b/build.server.sh
index 8c839f1..d1e85ec 100644
--- a/build.server.sh
+++ b/build.server.sh
@@ -1,28 +1,29 @@
-statik -m -src="./web/dist" -f -dest="./server/embed" -p web -ns web
+export GO111MODULE=auto
 mkdir ./releases
+export COMMIT=`git rev-parse HEAD`
 
 
 
 export GOOS=linux
 
 export GOARCH=arm
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_linux_arm Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_linux_arm Spark/server
 export GOARCH=arm64
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_linux_arm64 Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_linux_arm64 Spark/server
 export GOARCH=386
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_linux_i386 Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_linux_i386 Spark/server
 export GOARCH=amd64
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_linux_amd64 Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_linux_amd64 Spark/server
 
 
 
 export GOOS=windows
 
 export GOARCH=arm
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_windows_arm.exe Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_windows_arm.exe Spark/server
 export GOARCH=arm64
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_windows_arm64.exe Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_windows_arm64.exe Spark/server
 export GOARCH=386
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_windows_i386.exe Spark/server
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_windows_i386.exe Spark/server
 export GOARCH=amd64
-go build -ldflags "-s -w" -tags=jsoniter -o ./releases/server_windows_amd64.exe Spark/server
\ No newline at end of file
+go build -ldflags "-s -w -X 'Spark/server/config.COMMIT=$COMMIT'" -tags=jsoniter -o ./releases/server_windows_amd64.exe Spark/server
diff --git a/client/client.go b/client/client.go
index ee70dd8..31dbbfa 100644
--- a/client/client.go
+++ b/client/client.go
@@ -7,32 +7,29 @@ import (
 	"bytes"
 	"crypto/aes"
 	"crypto/cipher"
+	"io/ioutil"
 	"math/big"
 	"os"
+	"os/exec"
 	"strings"
+	"time"
 
 	"github.com/kataras/golog"
 )
 
-// localhost
-//var cfgBuffer = "\x00\xcd\x90\x50\x43\xfc\x3d\x36\x56\x6d\xf6\x01\xd1\xcd\x81\xc3\x1b\x80\xc9\x61\xd8\xdf\x5b\x76\x48\x88\xc5\xb1\x74\x22\x23\xab\x3b\xfc\x8b\xbe\x98\x27\xed\x05\xec\xbb\x40\x4f\xe9\xe7\xe5\xe0\x84\xaa\xb7\xfd\x4a\x30\x71\x08\x6c\x02\x50\xe9\xc5\x22\xcf\xcb\x89\x16\x0a\x89\x08\xd4\x26\xdc\x5c\xc1\xc9\xbf\xc4\xac\x0d\x92\x2f\x34\x7f\x45\xeb\x55\xa0\x6d\xf6\x64\xbc\xd5\x15\x40\x96\x43\x64\xe0\x24\x51\xfb\xe8\xc9\x7f\x48\x60\xcd\x30\x5e\x5e\x78\xba\xb6\x6f\x07\x64\xe8\x59\x81\x0b\x91\x13\x92\x1a\xdd\x49\x8f\x28\xe7\x74\xea\xff\x5b\x45\x0e\x4a\x2d\x60\x4e\xc9\xde\x9c\xbe\x50\xc6\x12\xc7\x45\xa2\x15\xa0\x58\x62\x45\x86\x74\x9f\xa5\x14\x5c\x17\x8a\xcc\x56\x73\xa7\x75\xb7\xf6\x6d\x52\x0f\xb8\xc1\xff\x9c\x39\x39\x00\x74\xe1\x4d\x65\x73\x9c\x02\x57\x8b\xcf\xdf\x0a\x20\x4c\xed\xe2\x25\xea\x01\x36\x12\x37\x12\x2e\x1a\x03\x41\x19\x2e\xc9\xdd\x71\xac\x73\x90\xfa\x5e\x60\x08\x43\x35\xef\x61\x45\xf9\xe3\xba\xcb\xb1\xc5\x7c\xf0\x11\xcd\x47\x57\x53\xdc\x35\x6b\x9f\xac\xad\x43\x4a\xc7\x54\x20\xb8\xd0\xf8\xb5\x0c\x45\x76\x57\xb9\xee\x4a\x3f\xd2\xda\xf7\x94\x54\x74\xf3\x91\xf3\x4d\x49\x98\xc6\xf8\x60\x80\xad\x84\x04\xef\x35\xca\x3a\xcf\xd3\x7e\x74\xc2\x4b\xb8\xb3\x9f\xb2\x83\xb8\xbd\x29\x13\x9f\x2b\xaa\x60\x47\x24\x7e\x20\xb2\x85\xdc\x47\xfe\x8f\x68\xb6\xc3\x43\xad\x61\x3d\x9b\x35\x60\x2e\x6c\x44\xf0\xaf\xb2\xf3\xdb\xe2\x1b\x8a\xec\x0a\x48\x5e\x43\xa9\xb3\x3a\x5e\xb6\x90\xa9\x3d\xee\x4f\xa1\x57\x7c\x94\xf4\xb1\x36\xda\x04\xa8\x5e\x48\x2a\xc3\xa1\xf0\x97\xf0\xe0\x10\x46\x32\x10\xe5\xd8\x36\x5a\x56\xa5\xbb\x37\x3c\x9f\xbd\xef\xf5\x2f"
-
-// none
-var cfgBuffer = "\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19"
-
 func init() {
 	golog.SetTimeFormat(`2006/01/02 15:04:05`)
 
-	if len(strings.Trim(cfgBuffer, "\x19")) == 0 {
+	if len(strings.Trim(config.CfgBuffer, "\x19")) == 0 {
 		os.Exit(0)
 		return
 	}
-	dataLen := int(big.NewInt(0).SetBytes([]byte(cfgBuffer[:2])).Uint64())
-	if dataLen > len(cfgBuffer)-2 {
+	dataLen := int(big.NewInt(0).SetBytes([]byte(config.CfgBuffer[:2])).Uint64())
+	if dataLen > len(config.CfgBuffer)-2 {
 		os.Exit(0)
 		return
 	}
-	cfgBytes := []byte(cfgBuffer[2 : 2+dataLen])
+	cfgBytes := []byte(config.CfgBuffer[2 : 2+dataLen])
 	cfgBytes, err := decrypt(cfgBytes[16:], cfgBytes[:16])
 	if err != nil {
 		os.Exit(0)
@@ -49,6 +46,27 @@ func init() {
 }
 
 func main() {
+	if len(os.Args) > 1 && os.Args[1] == `--update` {
+		thisPath := os.Args[0]
+		destPath := thisPath[:len(thisPath)-4]
+		if len(thisPath) <= 4 {
+			return
+		}
+		thisFile, err := ioutil.ReadFile(thisPath)
+		if err != nil {
+			return
+		}
+		ioutil.WriteFile(destPath, thisFile, 0755)
+		cmd := exec.Command(destPath, `--clean`)
+		if cmd.Start() == nil {
+			os.Exit(0)
+			return
+		}
+	}
+	if len(os.Args) > 1 && os.Args[1] == `--clean` {
+		<-time.After(time.Second)
+		os.Remove(os.Args[0] + `.tmp`)
+	}
 	core.Start()
 }
 
diff --git a/client/common/common.go b/client/common/common.go
index 5e6ceca..20011f5 100644
--- a/client/common/common.go
+++ b/client/common/common.go
@@ -31,7 +31,7 @@ func SendPack(pack interface{}, wsConn *Conn) error {
 		return err
 	}
 	if len(data) > 1024 {
-		_, err = req.C().R().
+		_, err = req.R().
 			SetBody(data).
 			SetHeader(`Secret`, hex.EncodeToString(wsConn.Secret)).
 			Send(`POST`, config.GetBaseURL(false)+`/ws`)
diff --git a/client/config/config.go b/client/config/config.go
index c32920c..453e93b 100644
--- a/client/config/config.go
+++ b/client/config/config.go
@@ -14,6 +14,14 @@ type Cfg struct {
 	Key    string `json:"key"`
 }
 
+// localhost
+//var CfgBuffer = "\x00\xcd\x90\x50\x43\xfc\x3d\x36\x56\x6d\xf6\x01\xd1\xcd\x81\xc3\x1b\x80\xc9\x61\xd8\xdf\x5b\x76\x48\x88\xc5\xb1\x74\x22\x23\xab\x3b\xfc\x8b\xbe\x98\x27\xed\x05\xec\xbb\x40\x4f\xe9\xe7\xe5\xe0\x84\xaa\xb7\xfd\x4a\x30\x71\x08\x6c\x02\x50\xe9\xc5\x22\xcf\xcb\x89\x16\x0a\x89\x08\xd4\x26\xdc\x5c\xc1\xc9\xbf\xc4\xac\x0d\x92\x2f\x34\x7f\x45\xeb\x55\xa0\x6d\xf6\x64\xbc\xd5\x15\x40\x96\x43\x64\xe0\x24\x51\xfb\xe8\xc9\x7f\x48\x60\xcd\x30\x5e\x5e\x78\xba\xb6\x6f\x07\x64\xe8\x59\x81\x0b\x91\x13\x92\x1a\xdd\x49\x8f\x28\xe7\x74\xea\xff\x5b\x45\x0e\x4a\x2d\x60\x4e\xc9\xde\x9c\xbe\x50\xc6\x12\xc7\x45\xa2\x15\xa0\x58\x62\x45\x86\x74\x9f\xa5\x14\x5c\x17\x8a\xcc\x56\x73\xa7\x75\xb7\xf6\x6d\x52\x0f\xb8\xc1\xff\x9c\x39\x39\x00\x74\xe1\x4d\x65\x73\x9c\x02\x57\x8b\xcf\xdf\x0a\x20\x4c\xed\xe2\x25\xea\x01\x36\x12\x37\x12\x2e\x1a\x03\x41\x19\x2e\xc9\xdd\x71\xac\x73\x90\xfa\x5e\x60\x08\x43\x35\xef\x61\x45\xf9\xe3\xba\xcb\xb1\xc5\x7c\xf0\x11\xcd\x47\x57\x53\xdc\x35\x6b\x9f\xac\xad\x43\x4a\xc7\x54\x20\xb8\xd0\xf8\xb5\x0c\x45\x76\x57\xb9\xee\x4a\x3f\xd2\xda\xf7\x94\x54\x74\xf3\x91\xf3\x4d\x49\x98\xc6\xf8\x60\x80\xad\x84\x04\xef\x35\xca\x3a\xcf\xd3\x7e\x74\xc2\x4b\xb8\xb3\x9f\xb2\x83\xb8\xbd\x29\x13\x9f\x2b\xaa\x60\x47\x24\x7e\x20\xb2\x85\xdc\x47\xfe\x8f\x68\xb6\xc3\x43\xad\x61\x3d\x9b\x35\x60\x2e\x6c\x44\xf0\xaf\xb2\xf3\xdb\xe2\x1b\x8a\xec\x0a\x48\x5e\x43\xa9\xb3\x3a\x5e\xb6\x90\xa9\x3d\xee\x4f\xa1\x57\x7c\x94\xf4\xb1\x36\xda\x04\xa8\x5e\x48\x2a\xc3\xa1\xf0\x97\xf0\xe0\x10\x46\x32\x10\xe5\xd8\x36\x5a\x56\xa5\xbb\x37\x3c\x9f\xbd\xef\xf5\x2f"
+
+// none
+var CfgBuffer = "\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19\x19"
+
+// COMMIT means this commit hash, for auto upgrade.
+var COMMIT = ``
 var Config Cfg
 
 func GetBaseURL(ws bool) string {
diff --git a/client/core/core.go b/client/core/core.go
index d6e445e..1241803 100644
--- a/client/core/core.go
+++ b/client/core/core.go
@@ -13,9 +13,13 @@ import (
 	"encoding/hex"
 	"errors"
 	ws "github.com/gorilla/websocket"
+	"github.com/imroc/req/v3"
 	"github.com/kataras/golog"
+	"io/ioutil"
 	"net/http"
 	"os"
+	"os/exec"
+	"runtime"
 	"strconv"
 	"time"
 )
@@ -48,6 +52,8 @@ func Start() {
 			continue
 		}
 
+		checkUpdate(common.WSConn)
+
 		go heartbeat(common.WSConn)
 
 		err = handleWS(common.WSConn)
@@ -106,6 +112,44 @@ func reportWS(wsConn *common.Conn) error {
 	return nil
 }
 
+func checkUpdate(wsConn *common.Conn) error {
+	if len(config.COMMIT) == 0 {
+		return nil
+	}
+	resp, err := req.R().
+		SetBody(config.CfgBuffer).
+		SetQueryParam(`os`, runtime.GOOS).
+		SetQueryParam(`arch`, runtime.GOARCH).
+		SetQueryParam(`commit`, config.COMMIT).
+		SetHeader(`Secret`, hex.EncodeToString(wsConn.Secret)).
+		Send(`POST`, config.GetBaseURL(false)+`/api/client/update`)
+	if err != nil {
+		return err
+	}
+	if resp == nil {
+		return errors.New(`unknown error occurred`)
+	}
+	if resp.GetContentType() == `application/octet-stream` {
+		body := resp.Bytes()
+		if len(body) > 0 {
+			err = ioutil.WriteFile(os.Args[0]+`.tmp`, body, 0755)
+			if err != nil {
+				return err
+			}
+			cmd := exec.Command(os.Args[0]+`.tmp`, `--update`)
+			err = cmd.Start()
+			if err != nil {
+				return err
+			}
+			stop = true
+			wsConn.Close()
+			os.Exit(0)
+		}
+		return nil
+	}
+	return nil
+}
+
 func handleWS(wsConn *common.Conn) error {
 	errCount := 0
 	for {
@@ -223,16 +267,21 @@ func handleAct(pack modules.Packet, wsConn *common.Conn) {
 			common.SendCb(modules.Packet{Code: 0, Data: smap{`files`: files}}, pack, wsConn)
 		}
 	case `removeFile`:
-		path, ok := pack.Data[`path`]
+		val, ok := pack.Data[`path`]
+		if !ok {
+			common.SendCb(modules.Packet{Code: 1, Msg: `can not find such a file or directory`}, pack, wsConn)
+			return
+		}
+		path, ok := val.(string)
 		if !ok {
 			common.SendCb(modules.Packet{Code: 1, Msg: `can not find such a file or directory`}, pack, wsConn)
 			return
 		}
-		if path == `\` || path == `/` || len(path.(string)) == 0 {
+		if path == `\` || path == `/` || len(path) == 0 {
 			common.SendCb(modules.Packet{Code: 1, Msg: `can not find such a file or directory`}, pack, wsConn)
 			return
 		}
-		err := os.RemoveAll(path.(string))
+		err := os.RemoveAll(path)
 		if err != nil {
 			common.SendCb(modules.Packet{Code: 1, Msg: err.Error()}, pack, wsConn)
 		} else {
@@ -307,15 +356,16 @@ func handleAct(pack modules.Packet, wsConn *common.Conn) {
 
 func heartbeat(wsConn *common.Conn) error {
 	t := 0
-	for range time.NewTicker(5 * time.Second).C {
+	for range time.NewTicker(2 * time.Second).C {
 		t++
-		// Get disk info every 30*5 seconds.
-		device, err := GetPartialInfo(t >= 30)
+		// GetPartialInfo always costs more than 1 second.
+		// So it is actually get disk info every 200*3 seconds (10 minutes).
+		device, err := GetPartialInfo(t >= 200)
 		if err != nil {
 			golog.Error(err)
 			continue
 		}
-		if t >= 30 {
+		if t >= 200 {
 			t = 0
 		}
 		err = common.SendPack(modules.CommonPack{Act: `setDevice`, Data: device}, wsConn)
diff --git a/client/core/device.go b/client/core/device.go
index de269c3..9b070c9 100644
--- a/client/core/device.go
+++ b/client/core/device.go
@@ -10,7 +10,8 @@ import (
 	"github.com/shirou/gopsutil/v3/disk"
 	"github.com/shirou/gopsutil/v3/host"
 	"github.com/shirou/gopsutil/v3/mem"
-	"net"
+	"github.com/shirou/gopsutil/v3/net"
+	_net "net"
 	"os"
 	"os/user"
 	"runtime"
@@ -18,8 +19,8 @@ import (
 	"time"
 )
 
-func isPrivateIP(ip net.IP) bool {
-	var privateIPBlocks []*net.IPNet
+func isPrivateIP(ip _net.IP) bool {
+	var privateIPBlocks []*_net.IPNet
 	for _, cidr := range []string{
 		//"127.0.0.0/8",    // IPv4 loopback
 		//"::1/128",        // IPv6 loopback
@@ -28,7 +29,7 @@ func isPrivateIP(ip net.IP) bool {
 		"172.16.0.0/12",  // RFC1918
 		"192.168.0.0/16", // RFC1918
 	} {
-		_, block, _ := net.ParseCIDR(cidr)
+		_, block, _ := _net.ParseCIDR(cidr)
 		privateIPBlocks = append(privateIPBlocks, block)
 	}
 	for _, block := range privateIPBlocks {
@@ -40,7 +41,7 @@ func isPrivateIP(ip net.IP) bool {
 }
 
 func GetLocalIP() (string, error) {
-	ifaces, err := net.Interfaces()
+	ifaces, err := _net.Interfaces()
 	if err != nil {
 		return `Unknown`, err
 	}
@@ -51,11 +52,11 @@ func GetLocalIP() (string, error) {
 		}
 
 		for _, addr := range addrs {
-			var ip net.IP
+			var ip _net.IP
 			switch v := addr.(type) {
-			case *net.IPNet:
+			case *_net.IPNet:
 				ip = v.IP
-			case *net.IPAddr:
+			case *_net.IPAddr:
 				ip = v.IP
 			}
 			if isPrivateIP(ip) {
@@ -71,7 +72,7 @@ func GetLocalIP() (string, error) {
 }
 
 func GetMacAddress() (string, error) {
-	interfaces, err := net.Interfaces()
+	interfaces, err := _net.Interfaces()
 	if err != nil {
 		return ``, err
 	}
@@ -88,6 +89,28 @@ func GetMacAddress() (string, error) {
 	return strings.ToUpper(address[0]), nil
 }
 
+func GetNetIOInfo() (modules.Net, error) {
+	result := modules.Net{}
+	first, err := net.IOCounters(false)
+	if err != nil {
+		return result, nil
+	}
+	if len(first) == 0 {
+		return result, errors.New(`failed to read network io counters`)
+	}
+	<-time.After(time.Second)
+	second, err := net.IOCounters(false)
+	if err != nil {
+		return result, nil
+	}
+	if len(second) == 0 {
+		return result, errors.New(`failed to read network io counters`)
+	}
+	result.Recv = second[0].BytesRecv - first[0].BytesRecv
+	result.Sent = second[0].BytesSent - first[0].BytesSent
+	return result, nil
+}
+
 func GetCPUInfo() (modules.CPU, error) {
 	result := modules.CPU{}
 	info, err := cpu.Info()
@@ -109,8 +132,8 @@ func GetCPUInfo() (modules.CPU, error) {
 	return result, nil
 }
 
-func GetMemInfo() (modules.Mem, error) {
-	result := modules.Mem{}
+func GetMemInfo() (modules.IO, error) {
+	result := modules.IO{}
 	stat, err := mem.VirtualMemory()
 	if err != nil {
 		return result, nil
@@ -121,8 +144,9 @@ func GetMemInfo() (modules.Mem, error) {
 	return result, nil
 }
 
-func GetDiskInfo() (modules.Disk, error) {
-	result := modules.Disk{}
+func GetDiskInfo() (modules.IO, error) {
+	result := modules.IO{}
+	disk.IOCounters()
 	disks, err := disk.Partitions(true)
 	if err != nil {
 		return result, nil
@@ -163,9 +187,16 @@ func GetDevice() (*modules.Device, error) {
 			Usage: 0,
 		}
 	}
+	netInfo, err := GetNetIOInfo()
+	if err != nil {
+		netInfo = modules.Net{
+			Sent: 0,
+			Recv: 0,
+		}
+	}
 	memInfo, err := GetMemInfo()
 	if err != nil {
-		memInfo = modules.Mem{
+		memInfo = modules.IO{
 			Total: 0,
 			Used:  0,
 			Usage: 0,
@@ -173,7 +204,7 @@ func GetDevice() (*modules.Device, error) {
 	}
 	diskInfo, err := GetDiskInfo()
 	if err != nil {
-		diskInfo = modules.Disk{
+		diskInfo = modules.IO{
 			Total: 0,
 			Used:  0,
 			Usage: 0,
@@ -203,6 +234,7 @@ func GetDevice() (*modules.Device, error) {
 		LAN:      localIP,
 		Mac:      macAddr,
 		CPU:      cpuInfo,
+		Net:      netInfo,
 		Mem:      memInfo,
 		Disk:     diskInfo,
 		Uptime:   uptime,
@@ -211,7 +243,7 @@ func GetDevice() (*modules.Device, error) {
 	}, nil
 }
 
-func GetPartialInfo(getDisk bool) (*modules.Device, error) {
+func GetPartialInfo(getDisk bool) (modules.Device, error) {
 	cpuInfo, err := GetCPUInfo()
 	if err != nil {
 		cpuInfo = modules.CPU{
@@ -219,9 +251,16 @@ func GetPartialInfo(getDisk bool) (*modules.Device, error) {
 			Usage: 0,
 		}
 	}
+	netInfo, err := GetNetIOInfo()
+	if err != nil {
+		netInfo = modules.Net{
+			Recv: 0,
+			Sent: 0,
+		}
+	}
 	memInfo, err := GetMemInfo()
 	if err != nil {
-		memInfo = modules.Mem{
+		memInfo = modules.IO{
 			Total: 0,
 			Used:  0,
 			Usage: 0,
@@ -229,7 +268,7 @@ func GetPartialInfo(getDisk bool) (*modules.Device, error) {
 	}
 	diskInfo, err := GetDiskInfo()
 	if err != nil {
-		diskInfo = modules.Disk{
+		diskInfo = modules.IO{
 			Total: 0,
 			Used:  0,
 			Usage: 0,
@@ -239,8 +278,9 @@ func GetPartialInfo(getDisk bool) (*modules.Device, error) {
 	if err != nil {
 		uptime = 0
 	}
-	return &modules.Device{
+	return modules.Device{
 		CPU:    cpuInfo,
+		Net:    netInfo,
 		Mem:    memInfo,
 		Disk:   diskInfo,
 		Uptime: uptime,
diff --git a/client/service/terminal/terminal.go b/client/service/terminal/terminal.go
index 61e9ff0..29a1c06 100644
--- a/client/service/terminal/terminal.go
+++ b/client/service/terminal/terminal.go
@@ -59,7 +59,7 @@ func InitTerminal(pack modules.Packet) error {
 			buffer := make([]byte, 512)
 			n, err := stdout.Read(buffer)
 			buffer = buffer[:n]
-			buffer, _ = gbkToUtf8(buffer)
+			buffer, _ = encodeUTF8(buffer)
 			common.SendCb(modules.Packet{Act: `outputTerminal`, Data: map[string]interface{}{
 				`output`: hex.EncodeToString(buffer),
 			}}, pack, common.WSConn)
@@ -74,7 +74,7 @@ func InitTerminal(pack modules.Packet) error {
 			buffer := make([]byte, 512)
 			n, err := stderr.Read(buffer)
 			buffer = buffer[:n]
-			buffer, _ = gbkToUtf8(buffer)
+			buffer, _ = encodeUTF8(buffer)
 			common.SendCb(modules.Packet{Act: `outputTerminal`, Data: map[string]interface{}{
 				`output`: hex.EncodeToString(buffer),
 			}}, pack, common.WSConn)
@@ -138,7 +138,7 @@ func InputTerminal(pack modules.Packet) error {
 		terminal.cmd.Process.Signal(os.Interrupt)
 		return nil
 	}
-	data, _ = utf8ToGbk(data)
+	data, _ = decodeUTF8(data)
 	(*terminal.stdin).Write(data)
 	return nil
 }
@@ -180,15 +180,33 @@ func doKillTerminal(terminal *terminal) {
 }
 
 func getTerminal() string {
-	switch runtime.GOOS {
-	case `windows`:
+	if runtime.GOOS == `windows` {
 		return `cmd.exe`
-	case `linux`:
-		return `sh`
-	case `darwin`:
-		return `sh`
-	default:
-		return `sh`
+	}
+	sh := []string{`bash`, `zsh`, `sh`}
+	for i := 0; i < len(sh); i++ {
+		f, err := os.Open(sh[i])
+		if err == nil {
+			f.Close()
+			return sh[i]
+		}
+	}
+	return `sh`
+}
+
+func encodeUTF8(s []byte) ([]byte, error) {
+	if runtime.GOOS == `windows` {
+		return gbkToUtf8(s)
+	} else {
+		return s, nil
+	}
+}
+
+func decodeUTF8(s []byte) ([]byte, error) {
+	if runtime.GOOS == `windows` {
+		return utf8ToGbk(s)
+	} else {
+		return s, nil
 	}
 }
 
diff --git a/modules/modules.go b/modules/modules.go
index c3c6d2e..3726d37 100644
--- a/modules/modules.go
+++ b/modules/modules.go
@@ -23,28 +23,28 @@ type Device struct {
 	LAN      string `json:"lan"`
 	WAN      string `json:"wan"`
 	Mac      string `json:"mac"`
+	Net      Net    `json:"net"`
 	CPU      CPU    `json:"cpu"`
-	Mem      Mem    `json:"mem"`
-	Disk     Disk   `json:"disk"`
+	Mem      IO     `json:"mem"`
+	Disk     IO     `json:"disk"`
 	Uptime   uint64 `json:"uptime"`
 	Latency  uint   `json:"latency"`
 	Hostname string `json:"hostname"`
 	Username string `json:"username"`
 }
 
-type CPU struct {
-	Model string  `json:"model"`
-	Usage float64 `json:"usage"`
-}
-
-type Mem struct {
+type IO struct {
 	Total uint64  `json:"total"`
 	Used  uint64  `json:"used"`
 	Usage float64 `json:"usage"`
 }
 
-type Disk struct {
-	Total uint64  `json:"total"`
-	Used  uint64  `json:"used"`
+type CPU struct {
+	Model string  `json:"model"`
 	Usage float64 `json:"usage"`
 }
+
+type Net struct {
+	Sent uint64 `json:"sent"`
+	Recv uint64 `json:"recv"`
+}
diff --git a/screenshots/overview.png b/screenshots/overview.png
index 95302f7..a1a3f5a 100644
Binary files a/screenshots/overview.png and b/screenshots/overview.png differ
diff --git a/server/common/common.go b/server/common/common.go
index 1ebe8a7..0499269 100644
--- a/server/common/common.go
+++ b/server/common/common.go
@@ -8,6 +8,8 @@ import (
 	"bytes"
 	"crypto/aes"
 	"crypto/cipher"
+	"encoding/hex"
+	"github.com/gin-gonic/gin"
 	"net/http"
 	"time"
 )
@@ -117,6 +119,28 @@ func WSHealthCheck(container *melody.Melody) {
 	}
 }
 
+func CheckClientReq(ctx *gin.Context, cb func(*melody.Session)) bool {
+	secret, err := hex.DecodeString(ctx.GetHeader(`Secret`))
+	if err != nil || len(secret) != 32 {
+		return false
+	}
+	find := false
+	Melody.IterSessions(func(uuid string, s *melody.Session) bool {
+		if val, ok := s.Get(`Secret`); ok {
+			// Check if there's a connection matches this secret.
+			if b, ok := val.([]byte); ok && bytes.Equal(b, secret) {
+				find = true
+				if cb != nil {
+					cb(s)
+				}
+				return false
+			}
+		}
+		return true
+	})
+	return find
+}
+
 func CheckDevice(deviceID string) (string, bool) {
 	connUUID := ``
 	Devices.IterCb(func(uuid string, v interface{}) bool {
diff --git a/server/config/config.go b/server/config/config.go
index be818b1..334abbc 100644
--- a/server/config/config.go
+++ b/server/config/config.go
@@ -8,3 +8,6 @@ type Cfg struct {
 }
 
 var Config Cfg
+
+// COMMIT means this commit hash, for auto upgrade.
+var COMMIT = ``
diff --git a/server/handler/file.go b/server/handler/file.go
index d84fd42..094294c 100644
--- a/server/handler/file.go
+++ b/server/handler/file.go
@@ -193,6 +193,7 @@ func getDeviceFile(ctx *gin.Context) {
 				ctx.Header(`Content-Length`, strconv.FormatInt(req.ContentLength, 10))
 			}
 			ctx.Header(`Accept-Ranges`, `bytes`)
+			ctx.Header(`Content-Transfer-Encoding`, `binary`)
 			ctx.Header(`Content-Type`, `application/octet-stream`)
 			filename := ctx.GetHeader(`FileName`)
 			if len(filename) == 0 {
diff --git a/server/handler/generate.go b/server/handler/generate.go
index 033144f..bc3e8b4 100644
--- a/server/handler/generate.go
+++ b/server/handler/generate.go
@@ -136,6 +136,7 @@ func generateClient(ctx *gin.Context) {
 	} else {
 		ctx.Header(`Content-Disposition`, `attachment; filename=client;`)
 	}
+	// Find and replace plain buffer with encrypted configuration.
 	cfgBuffer := bytes.Repeat([]byte{'\x19'}, 384)
 	prevBuffer := make([]byte, 0)
 	for {
@@ -173,6 +174,7 @@ func genConfig(cfg clientCfg) ([]byte, error) {
 	if len(final) > 384-2 {
 		return nil, errTooLargeEntity
 	}
+
 	dataLen := big.NewInt(int64(len(final))).Bytes()
 	dataLen = append(bytes.Repeat([]byte{'\x00'}, 2-len(dataLen)), dataLen...)
 
diff --git a/server/handler/handler.go b/server/handler/handler.go
index 9eee9f6..fd7721d 100644
--- a/server/handler/handler.go
+++ b/server/handler/handler.go
@@ -3,20 +3,24 @@ package handler
 import (
 	"Spark/modules"
 	"Spark/server/common"
+	"Spark/server/config"
 	"Spark/utils"
 	"Spark/utils/melody"
+	"bytes"
 	"fmt"
 	"github.com/gin-gonic/gin"
 	"github.com/kataras/golog"
 	"net/http"
+	"strconv"
 	"time"
 )
 
-// APIRouter 负责分配各种API接口
+// APIRouter will initialize http and websocket routers.
 func APIRouter(ctx *gin.RouterGroup, auth gin.HandlerFunc) {
-	ctx.PUT(`/device/screenshot/put`, putScreenshot)
-	ctx.PUT(`/device/file/put`, putDeviceFile)
-	ctx.Any(`/device/terminal`, initTerminal)
+	ctx.PUT(`/device/screenshot/put`, putScreenshot) // Client, upload screenshot and forward to browser.
+	ctx.PUT(`/device/file/put`, putDeviceFile)       // Client, to upload file and forward to browser.
+	ctx.Any(`/device/terminal`, initTerminal)        // Browser, handle websocket events for web terminal.
+	ctx.Any(`/client/update`, checkUpdate)           // Client, for update.
 	group := ctx.Group(`/`, auth)
 	{
 		group.POST(`/device/screenshot/get`, getScreenshot)
@@ -32,7 +36,73 @@ func APIRouter(ctx *gin.RouterGroup, auth gin.HandlerFunc) {
 	}
 }
 
-// putScreenshot 负责获取client发送过来的屏幕截图
+// checkUpdate will check if client need update and return latest client if so.
+func checkUpdate(ctx *gin.Context) {
+	var form struct {
+		OS     string `form:"os" binding:"required"`
+		Arch   string `form:"arch" binding:"required"`
+		Commit string `form:"commit" binding:"required"`
+	}
+	if err := ctx.ShouldBind(&form); err != nil {
+		golog.Error(err)
+		ctx.JSON(http.StatusBadRequest, modules.Packet{Code: -1, Msg: `参数不完整`})
+		return
+	}
+	if form.Commit == config.COMMIT {
+		ctx.JSON(http.StatusOK, modules.Packet{Code: 0})
+		return
+	}
+	tpl, err := common.BuiltFS.Open(fmt.Sprintf(`/%v_%v`, form.OS, form.Arch))
+	if err != nil {
+		ctx.JSON(http.StatusNotFound, modules.Packet{Code: 1, Msg: `该系统或架构的客户端尚未编译`})
+		return
+	}
+
+	const MaxBodySize = 384 // This is size of client config buffer.
+	if ctx.Request.ContentLength > MaxBodySize {
+		ctx.JSON(http.StatusRequestEntityTooLarge, modules.Packet{Code: 1})
+		return
+	}
+	body, err := ctx.GetRawData()
+	if err != nil {
+		ctx.JSON(http.StatusBadRequest, modules.Packet{Code: 1})
+		return
+	}
+	auth := common.CheckClientReq(ctx, nil)
+	if !auth {
+		ctx.JSON(http.StatusUnauthorized, modules.Packet{Code: 1})
+	}
+
+	ctx.Header(`Accept-Ranges`, `none`)
+	ctx.Header(`Content-Transfer-Encoding`, `binary`)
+	ctx.Header(`Content-Type`, `application/octet-stream`)
+	if stat, err := tpl.Stat(); err == nil {
+		ctx.Header(`Content-Length`, strconv.FormatInt(stat.Size(), 10))
+	}
+	cfgBuffer := bytes.Repeat([]byte{'\x19'}, 384)
+	prevBuffer := make([]byte, 0)
+	for {
+		thisBuffer := make([]byte, 1024)
+		n, err := tpl.Read(thisBuffer)
+		thisBuffer = thisBuffer[:n]
+		tempBuffer := append(prevBuffer, thisBuffer...)
+		bufIndex := bytes.Index(tempBuffer, cfgBuffer)
+		if bufIndex > -1 {
+			tempBuffer = bytes.Replace(tempBuffer, cfgBuffer, body, -1)
+		}
+		ctx.Writer.Write(tempBuffer[:len(prevBuffer)])
+		prevBuffer = tempBuffer[len(prevBuffer):]
+		if err != nil {
+			break
+		}
+	}
+	if len(prevBuffer) > 0 {
+		ctx.Writer.Write(prevBuffer)
+		prevBuffer = []byte{}
+	}
+}
+
+// putScreenshot will forward screenshot image from client to browser.
 func putScreenshot(ctx *gin.Context) {
 	errMsg := ctx.GetHeader(`Error`)
 	trigger := ctx.GetHeader(`Trigger`)
@@ -76,7 +146,7 @@ func putScreenshot(ctx *gin.Context) {
 	ctx.JSON(http.StatusOK, modules.Packet{Code: 0})
 }
 
-// getScreenshot 负责发送指令给client，让其截图
+// getScreenshot will call client to screenshot.
 func getScreenshot(ctx *gin.Context) {
 	var form struct {
 		Conn   string `json:"uuid" yaml:"uuid" form:"uuid"`
@@ -125,7 +195,7 @@ func getScreenshot(ctx *gin.Context) {
 	}
 }
 
-// getDevices 负责获取所有device的基本信息
+// getDevices will return all info about all clients.
 func getDevices(ctx *gin.Context) {
 	devices := make(map[string]modules.Device)
 	common.Devices.IterCb(func(uuid string, v interface{}) bool {
@@ -138,7 +208,7 @@ func getDevices(ctx *gin.Context) {
 	ctx.JSON(http.StatusOK, modules.CommonPack{Code: 0, Data: devices})
 }
 
-// callDevice 负责把HTTP网关发送的请求转发给client
+// callDevice will call client with command from browser.
 func callDevice(ctx *gin.Context) {
 	var form struct {
 		Conn   string `json:"uuid" yaml:"uuid" form:"uuid"`
@@ -178,7 +248,8 @@ func callDevice(ctx *gin.Context) {
 	}
 }
 
-// WSDevice 负责处理client设备信息上报的事件
+// WSDevice handles events about device info.
+// Such as websocket handshake and update device info.
 func WSDevice(data []byte, session *melody.Session) error {
 	var pack struct {
 		Code   int            `json:"code,omitempty"`
@@ -230,6 +301,7 @@ func WSDevice(data []byte, session *melody.Session) error {
 			deviceInfo, ok := val.(*modules.Device)
 			if ok {
 				deviceInfo.CPU = pack.Device.CPU
+				deviceInfo.Net = pack.Device.Net
 				deviceInfo.Mem = pack.Device.Mem
 				if pack.Device.Disk.Total > 0 {
 					deviceInfo.Disk = pack.Device.Disk
@@ -243,8 +315,7 @@ func WSDevice(data []byte, session *melody.Session) error {
 	return nil
 }
 
-// WSRouter 负责处理client回复的packet
+// WSRouter handles all packets from client.
 func WSRouter(pack modules.Packet, session *melody.Session) {
-
 	common.CallEvent(pack, session)
 }
diff --git a/server/main.go b/server/main.go
index 42d0eb7..96d7a13 100644
--- a/server/main.go
+++ b/server/main.go
@@ -62,11 +62,11 @@ func main() {
 	}
 	app := gin.New()
 	auth := gin.BasicAuth(config.Config.Auth)
+	handler.APIRouter(app.Group(`/api`), auth)
+	app.Any(`/ws`, wsHandshake)
 	app.NoRoute(auth, func(ctx *gin.Context) {
 		http.FileServer(webFS).ServeHTTP(ctx.Writer, ctx.Request)
 	})
-	handler.APIRouter(app.Group(`/api`), auth)
-	app.Any(`/ws`, wsHandshake)
 
 	common.Melody.Config.MaxMessageSize = 1024
 	common.Melody.HandleConnect(wsOnConnect)
@@ -126,26 +126,23 @@ func wsHandshake(ctx *gin.Context) {
 	} else {
 		// When message is too large to transport via websocket,
 		// client will try to send these data via http.
-		// Here is the data validator.
-		const MaxBufferSize = 2 << 18 //524288 512KB
-		secret, err := hex.DecodeString(ctx.GetHeader(`Secret`))
-		if err != nil || len(secret) != 32 {
+		const MaxBodySize = 2 << 18 //524288 512KB
+		if ctx.Request.ContentLength > MaxBodySize {
+			ctx.JSON(http.StatusRequestEntityTooLarge, modules.Packet{Code: 1})
 			return
 		}
 		body, err := ctx.GetRawData()
 		if err != nil {
+			ctx.JSON(http.StatusBadRequest, modules.Packet{Code: 1})
 			return
 		}
-		common.Melody.IterSessions(func(uuid string, s *melody.Session) bool {
-			if val, ok := s.Get(`Secret`); ok {
-				// Check if there's the connection with the secret.
-				if b, ok := val.([]byte); ok && bytes.Equal(b, secret) {
-					wsOnMessageBinary(s, body)
-					return false
-				}
-			}
-			return true
+		auth := common.CheckClientReq(ctx, func(s *melody.Session) {
+			wsOnMessageBinary(s, body)
 		})
+		if !auth {
+			ctx.JSON(http.StatusUnauthorized, modules.Packet{Code: 1})
+		}
+		ctx.JSON(http.StatusOK, modules.Packet{Code: 0})
 	}
 }
 
diff --git a/web/build.web.bat b/web/build.web.bat
index 6078731..199ca92 100644
--- a/web/build.web.bat
+++ b/web/build.web.bat
@@ -1 +1,2 @@
-npm run build-prod
\ No newline at end of file
+npm run build-prod
+statik -m -src="../web/dist" -f -dest="../server/embed" -p web -ns web
\ No newline at end of file
diff --git a/web/src/index.js b/web/src/index.js
index c6f35b4..df80207 100644
--- a/web/src/index.js
+++ b/web/src/index.js
@@ -13,7 +13,6 @@ import 'dayjs/locale/zh-cn';
 import Overview from "./pages/overview";
 
 dayjs.locale('zh-cn');
-console.log("%c By XZB", 'font-family:"Helvetica Neue",Helvetica,Arial,sans-serif;font-size:64px;color:#00bbee;-webkit-text-fill-color:#00bbee;-webkit-text-stroke:1px#00bbee;');
 
 axios.defaults.baseURL = '.';
 axios.interceptors.response.use(async (res) => {
diff --git a/web/src/pages/overview.js b/web/src/pages/overview.js
index 2134e25..7ebd665 100644
--- a/web/src/pages/overview.js
+++ b/web/src/pages/overview.js
@@ -10,6 +10,9 @@ import {QuestionCircleOutlined} from "@ant-design/icons";
 
 import defaultColumnsState from "../config/columnsState.json";
 
+// DO NOT EDIT OR DELETE THIS COPYRIGHT MESSAGE.
+console.log("%c By XZB %c https://github.com/XZB-1248/Spark", 'font-family:"Helvetica Neue",Helvetica,Arial,sans-serif;font-size:64px;color:#00bbee;-webkit-text-fill-color:#00bbee;-webkit-text-stroke:1px#00bbee;', 'font-size:12px;');
+
 function overview(props) {
     const [procMgr, setProcMgr] = useState(false);
     const [browser, setBrowser] = useState(false);
@@ -33,7 +36,7 @@ function overview(props) {
             title: 'Username',
             dataIndex: 'username',
             ellipsis: true,
-            width: 100
+            width: 90
         },
         {
             key: 'ping',
@@ -48,7 +51,7 @@ function overview(props) {
             title: 'CPU Usage',
             dataIndex: 'cpu_usage',
             ellipsis: true,
-            render: (_, v) => <Progress percent={v.cpu_usage} showInfo={false} strokeWidth={12} />,
+            render: (_, v) => <Progress percent={v.cpu_usage} showInfo={false} strokeWidth={12} trailColor='#FFECFF'/>,
             width: 100
         },
         {
@@ -56,7 +59,7 @@ function overview(props) {
             title: 'Mem Usage',
             dataIndex: 'mem_usage',
             ellipsis: true,
-            render: (_, v) => <Progress percent={v.mem_usage} showInfo={false} strokeWidth={12} />,
+            render: (_, v) => <Progress percent={v.mem_usage} showInfo={false} strokeWidth={12} trailColor='#FFECFF'/>,
             width: 100
         },
         {
@@ -64,9 +67,17 @@ function overview(props) {
             title: 'Disk Usage',
             dataIndex: 'disk_usage',
             ellipsis: true,
-            render: (_, v) => <Progress percent={v.disk_usage} showInfo={false} strokeWidth={12} />,
+            render: (_, v) => <Progress percent={v.disk_usage} showInfo={false} strokeWidth={12} trailColor='#FFECFF'/>,
             width: 100
         },
+        {
+            key: 'mem_total',
+            title: 'Mem',
+            dataIndex: 'mem_total',
+            ellipsis: true,
+            renderText: formatSize,
+            width: 70
+        },
         {
             key: 'os',
             title: 'OS',
@@ -102,14 +113,6 @@ function overview(props) {
             ellipsis: true,
             width: 100
         },
-        {
-            key: 'mem_total',
-            title: 'Mem',
-            dataIndex: 'mem_total',
-            ellipsis: true,
-            renderText: formatSize,
-            width: 70
-        },
         {
             key: 'uptime',
             title: 'Uptime',
@@ -118,14 +121,21 @@ function overview(props) {
             renderText: tsToTime,
             width: 100
         },
+        {
+            key: 'net_stat',
+            title: 'Network IO',
+            ellipsis: true,
+            renderText: (_, v) => renderNetworkIO(v),
+            width: 170
+        },
         {
             key: 'option',
-            width: 180,
             title: '操作',
             dataIndex: 'id',
             valueType: 'option',
             ellipsis: true,
-            render: (_, device) => renderOperation(device)
+            render: (_, device) => renderOperation(device),
+            width: 170
         },
     ];
     const options = {
@@ -165,6 +175,22 @@ function overview(props) {
         localStorage.setItem(`columnsState`, JSON.stringify(stateMap));
     }
 
+    function renderNetworkIO(device) {
+        // Make unit starts with Kbps.
+        let sent = device.net_sent * 8 / 1024;
+        let recv = device.net_recv * 8 / 1024;
+        return `${format(sent)} ↑ / ${format(recv)} ↓`;
+
+        function format(size) {
+            if (size <= 1) return '0 Kbps';
+            // Units array is large enough.
+            let k = 1024,
+                i = Math.floor(Math.log(size) / Math.log(k)),
+                units = ['Kbps', 'Mbps', 'Gbps', 'Tbps'];
+            return (size / Math.pow(k, i)).toFixed(1) + ' ' + units[i];
+        }
+    }
+
     function renderOperation(device) {
         return [
             <a key='terminal' onClick={setTerminal.bind(null, device.id)}>终端</a>,
diff --git a/web/src/utils/utils.js b/web/src/utils/utils.js
index 18f81b7..ff014d7 100644
--- a/web/src/utils/utils.js
+++ b/web/src/utils/utils.js
@@ -22,12 +22,12 @@ function waitTime(time) {
     });
 };
 
-function formatSize(bytes) {
-    if (bytes === 0) return 'Unknown';
+function formatSize(size) {
+    if (size === 0) return 'Unknown';
     let k = 1024,
-        i = Math.floor(Math.log(bytes) / Math.log(k)),
-        sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
-    return (bytes / Math.pow(k, i)).toFixed(2) + ' ' + sizes[i];
+        i = Math.floor(Math.log(size) / Math.log(k)),
+        units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
+    return (size / Math.pow(k, i)).toFixed(2) + ' ' + units[i];
 }
 
 function tsToTime(ts) {