Updated README

README.md

@@ -8,8 +8,8 @@ GoDoc at https://godoc.org/github.com/riobard/go-shadowsocks2/
 ## Features
 
 - SOCKS5 proxy 
-- Netfilter TCP redirect (IPv6 should work but not tested)
-- UDP tunneling (e.g. tunneling DNS)
+- Support for Netfilter TCP redirect (IPv6 should work but not tested)
+- UDP tunneling (e.g. relay DNS packets)
 - TCP tunneling (e.g. benchmark with iperf3)
 
 
@@ -20,7 +20,7 @@ go install github.com/riobard/go-shadowsocks2
 ```
 
 
-## Usage
+## Basic Usage
 
 
 ### Server
@@ -38,10 +38,73 @@ go-shadowsocks2 -s :8488 -cipher aes-128-gcm -key 1234567890abcdef1234567890abcd
 
 Start a client connecting to the above server. The client listens on port 1080 for incoming SOCKS5 
 connections, and tunnels UDP packets received on port 1080 and port 1081 to 8.8.8.8:53 and 8.8.4.4:53 
-respectively. The client also tunnels TCP connection to port 1082 to port 5201 on localhost, which is
-used to proxy iperf3 for benchmarking.
+respectively. 
 
 ```sh
 go-shadowsocks2 -c [server_address]:8488 -cipher aes-128-gcm -key 1234567890abcdef1234567890abcdef \
-    -socks :1080 -udptun :1080=8.8.8.8:53,:1081=8.8.4.4:53 -tcptun :1082=localhost:5201 -verbose
+    -socks :1080 -udptun :1080=8.8.8.8:53,:1081=8.8.4.4:53 -verbose
 ```
+
+
+
+## Advanced Usage
+
+
+### Netfilter TCP redirect (Linux only)
+
+The client offers `-redir` and `-redir6` (for IPv6) options to handle TCP connections 
+redirected by Netfilter on Linux. The feature works similar to `ss-redir` from `shadowsocks-libev`.
+
+
+Start a client listening on port 1082 for redirected TCP connections and port 1083 for redirected
+TCP IPv6 connections.
+
+```sh
+go-shadowsocks2 -c [server_address]:8488 -cipher aes-128-gcm -key 1234567890abcdef1234567890abcdef \
+    -redir :1082 -redir6 :1083
+```
+
+
+### TCP tunneling
+
+The client offers `-tcptun [local_addr]:[local_port]=[remote_addr]:[remote_port]` option to tunnel TCP.
+For example it can be used to proxy iperf3 for benchmarking.
+
+Start iperf3 on the same machine with the server.
+
+```sh
+iperf3 -s
+```
+
+By default iperf3 listens on port 5201.
+
+Start a client on the same machine with the server. The client listens on port 1090 for incoming connections
+and tunnels to localhost:5201 where iperf3 is listening.
+
+```sh
+go-shadowsocks2 -c [server_address]:8488 -cipher aes-128-gcm -key 1234567890abcdef1234567890abcdef \
+    -tcptun :1090=localhost:5201
+```
+
+Start iperf3 client to connect to the tunneld port instead
+
+```sh
+iperf3 -c localhost -p 1090
+```
+
+
+## TODO
+
+- Test coverage
+- Binary releases for common platforms
+
+
+
+## Design Principles
+
+The code base strives to
+
+- be idiomatic Go and well organized;
+- use fewer external dependences as reasonably possible;
+- only include proven modern ciphers;
+