diff --git a/conn_test.go b/conn_test.go
new file mode 100644
index 0000000..941327a
--- /dev/null
+++ b/conn_test.go
@@ -0,0 +1,150 @@
+package obfssh
+
+import (
+	"fmt"
+	"net"
+	"testing"
+	"time"
+)
+
+func TestObfsConn(t *testing.T) {
+	obfsMethod := "rc4"
+	obfsKey := "hello"
+
+	// test rc4
+	testObfsConn(t, obfsMethod, obfsKey)
+
+	obfsMethod = "aes"
+
+	// test aes
+	testObfsConn(t, obfsMethod, obfsKey)
+}
+
+func testObfsConn(t *testing.T, obfsMethod, obfsKey string) {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen socket failed: %s", err)
+	}
+
+	defer l.Close()
+
+	addr := l.Addr()
+
+	go func() {
+		// server
+		s, err := l.Accept()
+		if err != nil {
+			t.Fatalf("acceept failed: %s", err)
+		}
+
+		defer s.Close()
+
+		sConn, err := NewObfsConn(s, obfsMethod, obfsKey, true)
+		if err != nil {
+			t.Fatalf("create obfsconn failed: %s", err)
+		}
+
+		buf := make([]byte, 100)
+		n, err := sConn.Read(buf)
+		if err != nil {
+			t.Fatalf("server read failed: %s", err)
+		}
+
+		sConn.Write(buf[:n])
+	}()
+
+	c, err := net.Dial("tcp", addr.String())
+	if err != nil {
+		t.Fatalf("dail failed: %s", err)
+	}
+
+	defer c.Close()
+
+	cConn, err := NewObfsConn(c, obfsMethod, obfsKey, false)
+	if err != nil {
+		t.Fatalf("create client obfsconn failed: %s", err)
+	}
+
+	str := "hello, world"
+	cConn.Write([]byte(str))
+
+	buf := make([]byte, 100)
+	n, err := cConn.Read(buf)
+
+	if str != string(buf[:n]) {
+		t.Errorf("data transport failed")
+	}
+}
+
+func TestTimedOutConn(t *testing.T) {
+	testTimedOutConn(t, false)
+	testTimedOutConn(t, true)
+}
+
+func testTimedOutConn(t *testing.T, timeout bool) {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("listen failed: %s", err)
+	}
+
+	// timeout time
+	timeout_t := 1 * time.Second
+
+	defer l.Close()
+
+	addr := l.Addr()
+
+	go func() {
+		s, err := l.Accept()
+		if err != nil {
+			t.Fatalf("accept failed: %s", err)
+		}
+
+		defer s.Close()
+
+		sConn := TimedOutConn{s, timeout_t}
+
+		buf := make([]byte, 100)
+
+		n, err := sConn.Read(buf)
+		if err != nil {
+			t.Fatalf("server read failed: %s", err)
+		}
+
+		if timeout {
+			time.Sleep(timeout_t + 1*time.Second)
+		}
+
+		sConn.Write(buf[:n])
+	}()
+
+	c, err := net.Dial("tcp", addr.String())
+	if err != nil {
+		t.Fatalf("dial failed: %s", err)
+	}
+
+	defer c.Close()
+
+	str := "hello, world"
+
+	cConn := TimedOutConn{c, timeout_t}
+
+	if _, err := cConn.Write([]byte(str)); err != nil {
+		t.Fatalf("client write failed: %s", err)
+	}
+
+	buf := make([]byte, 100)
+
+	n, err := cConn.Read(buf)
+	if timeout {
+		if err == nil {
+			t.Errorf("expeced timeout error, got nil")
+		} else {
+			fmt.Println(err)
+		}
+	} else {
+		if str != string(buf[:n]) {
+			t.Errorf("data transport failed")
+		}
+	}
+}