!8 Specification NestOS Project Component Description File

From: @duyiwei7w 
Reviewed-by: @fu-shanqing 
Signed-off-by: @fu-shanqing

README.md

@@ -1,30 +1,50 @@
 # slirp4netns
 
 #### 介绍
-User-mode networking for unprivileged network namespaces.
-
-#### 软件架构
-软件架构说明
+slirp4netns provides user-mode networking ("slirp") for unprivileged network namespaces.
 
 
 #### 安装教程
 
-1.  xxxx
-2.  xxxx
-3.  xxxx
+Install slirp4netns rpm package:
+
+yum install slirp4netns
 
 #### 使用说明
 
-1.  xxxx
-2.  xxxx
-3.  xxxx
+**Terminal 1**: Create user/network/mount namespaces
+
+```console
+(host)$ unshare --user --map-root-user --net --mount
+(namespace)$ echo $$ > /tmp/pid
+```
+
+In this documentation, we use `(host)$` as the prompt of the host shell, `(namespace)$` as the prompt of the shell running in the namespaces.
+
+If `unshare` fails, try the following commands (known to be needed on Debian, Arch, and old CentOS 7.X):
+
+```console
+(host)$ sudo sh -c 'echo "user.max_user_namespaces=28633" >> /etc/sysctl.d/userns.conf'
+(host)$ [ -f /proc/sys/kernel/unprivileged_userns_clone ] && sudo sh -c 'echo "kernel.unprivileged_userns_clone=1" >> /etc/sysctl.d/userns.conf'
+(host)$ sudo sysctl --system
+```
+
+**Terminal 2**: Start slirp4netns
+
+```console
+(host)$ slirp4netns --configure --mtu=65520 --disable-host-loopback $(cat /tmp/pid) tap0
+starting slirp, MTU=65520
+...
+```
 
 #### 参与贡献
 
-1.  Fork 本仓库
-2.  新建 Feat_xxx 分支
-3.  提交代码
-4.  新建 Pull Request
+master分支使用最新的上游版本，如果检测到上游有最新版本发布，先形成issue后再提交对应PR更新，流程如下。
+1.  提交issue
+2.  Fork 本仓库
+3.  新建 Feat_xxx 分支
+4.  提交代码
+5.  新建 Pull Request
 
 
 #### 特技