diff --git a/client/client.go b/client/client.go
index 64910f6..377bb62 100755
--- a/client/client.go
+++ b/client/client.go
@@ -2,6 +2,11 @@ package client
 
 import (
 	"bufio"
+	"net"
+	"net/http"
+	"strconv"
+	"time"
+
 	"github.com/cnlh/nps/lib/common"
 	"github.com/cnlh/nps/lib/config"
 	"github.com/cnlh/nps/lib/conn"
@@ -9,10 +14,6 @@ import (
 	"github.com/cnlh/nps/lib/mux"
 	"github.com/cnlh/nps/vender/github.com/astaxie/beego/logs"
 	"github.com/cnlh/nps/vender/github.com/xtaci/kcp"
-	"net"
-	"net/http"
-	"strconv"
-	"time"
 )
 
 type TRPClient struct {
@@ -159,7 +160,7 @@ func (s *TRPClient) handleChan(src net.Conn) {
 	lk.Host = common.FormatAddress(lk.Host)
 	//if Conn type is http, read the request and log
 	if lk.ConnType == "http" {
-		if targetConn, err := net.Dial(common.CONN_TCP, lk.Host); err != nil {
+		if targetConn, err := net.DialTimeout(common.CONN_TCP, lk.Host, lk.Option.Timeout); err != nil {
 			logs.Warn("connect to %s error %s", lk.Host, err.Error())
 			src.Close()
 		} else {
@@ -183,7 +184,7 @@ func (s *TRPClient) handleChan(src net.Conn) {
 		return
 	}
 	//connect to target if conn type is tcp or udp
-	if targetConn, err := net.Dial(lk.ConnType, lk.Host); err != nil {
+	if targetConn, err := net.DialTimeout(lk.ConnType, lk.Host, lk.Option.Timeout); err != nil {
 		logs.Warn("connect to %s error %s", lk.Host, err.Error())
 		src.Close()
 	} else {
diff --git a/lib/conn/link.go b/lib/conn/link.go
index 974827d..653894e 100644
--- a/lib/conn/link.go
+++ b/lib/conn/link.go
@@ -1,5 +1,7 @@
 package conn
 
+import "time"
+
 type Secret struct {
 	Password string
 	Conn     *Conn
@@ -19,9 +21,20 @@ type Link struct {
 	Compress   bool
 	LocalProxy bool
 	RemoteAddr string
+	Option     Options
 }
 
-func NewLink(connType string, host string, crypt bool, compress bool, remoteAddr string, localProxy bool) *Link {
+type Option func(*Options)
+
+type Options struct {
+	Timeout time.Duration
+}
+
+var defaultTimeOut = time.Second * 5
+
+func NewLink(connType string, host string, crypt bool, compress bool, remoteAddr string, localProxy bool, opts ...Option) *Link {
+	options := newOptions(opts...)
+
 	return &Link{
 		RemoteAddr: remoteAddr,
 		ConnType:   connType,
@@ -29,5 +42,22 @@ func NewLink(connType string, host string, crypt bool, compress bool, remoteAddr
 		Crypt:      crypt,
 		Compress:   compress,
 		LocalProxy: localProxy,
+		Option:     options,
+	}
+}
+
+func newOptions(opts ...Option) Options {
+	opt := Options{
+		Timeout: defaultTimeOut,
+	}
+	for _, o := range opts {
+		o(&opt)
+	}
+	return opt
+}
+
+func LinkTimeout(t time.Duration) Option {
+	return func(opt *Options) {
+		opt.Timeout = t
 	}
 }
diff --git a/lib/mux/conn.go b/lib/mux/conn.go
index 9e66577..2c9abac 100644
--- a/lib/mux/conn.go
+++ b/lib/mux/conn.go
@@ -93,7 +93,8 @@ func (s *conn) Write(buf []byte) (int, error) {
 	if s.isClose {
 		return 0, errors.New("the conn has closed")
 	}
-	ch := make(chan struct{})
+	ch := make(chan error)
+	var err error
 	go s.write(buf, ch)
 	if t := s.writeTimeOut.Sub(time.Now()); t > 0 {
 		timer := time.NewTimer(t)
@@ -101,17 +102,20 @@ func (s *conn) Write(buf []byte) (int, error) {
 		select {
 		case <-timer.C:
 			return 0, errors.New("write timeout")
-		case <-ch:
+		case err = <-ch:
 		}
 	} else {
-		<-ch
+		err = <-ch
 	}
 	if s.isClose {
 		return 0, io.EOF
 	}
+	if err != nil {
+		return 0, err
+	}
 	return len(buf), nil
 }
-func (s *conn) write(buf []byte, ch chan struct{}) {
+func (s *conn) write(buf []byte, ch chan error) {
 	start := 0
 	l := len(buf)
 	for {
@@ -120,14 +124,18 @@ func (s *conn) write(buf []byte, ch chan struct{}) {
 		}
 		s.hasWrite++
 		if l-start > pool.PoolSizeCopy {
-			s.mux.sendInfo(MUX_NEW_MSG, s.connId, buf[start:start+pool.PoolSizeCopy])
+			if err := s.mux.sendInfo(MUX_NEW_MSG, s.connId, buf[start:start+pool.PoolSizeCopy]); err != nil {
+				ch <- err
+			}
 			start += pool.PoolSizeCopy
 		} else {
-			s.mux.sendInfo(MUX_NEW_MSG, s.connId, buf[start:l])
+			if err := s.mux.sendInfo(MUX_NEW_MSG, s.connId, buf[start:l]); err != nil {
+				ch <- err
+			}
 			break
 		}
 	}
-	ch <- struct{}{}
+	ch <- nil
 }
 
 func (s *conn) Close() error {