diff --git a/connection.go b/connection.go
index 6026ffc..d6f3436 100644
--- a/connection.go
+++ b/connection.go
@@ -1,7 +1,9 @@
 package srpc
 
 import (
+	"io"
 	"net"
+	"sync"
 )
 
 type RPCStatus uint8
@@ -40,7 +42,6 @@ type TCPConn struct {
 
 func (tc *TCPConn) ReceiveRequest() (ret *RPCRequest, err error) {
 	ret = new(RPCRequest)
-	err = nil
 
 	dec := tc.ed.NewDecoder(tc.conn)
 	if err = dec.Decode(ret); err != nil {
@@ -52,7 +53,6 @@ func (tc *TCPConn) ReceiveRequest() (ret *RPCRequest, err error) {
 
 func (tc *TCPConn) ReceiveResponse() (ret *RPCResponse, err error) {
 	ret = new(RPCResponse)
-	err = nil
 
 	dec := tc.ed.NewDecoder(tc.conn)
 	if err = dec.Decode(ret); err != nil {
@@ -63,8 +63,6 @@ func (tc *TCPConn) ReceiveResponse() (ret *RPCResponse, err error) {
 }
 
 func (tc *TCPConn) SendRequest(request *RPCRequest) (err error) {
-	err = nil
-
 	enc := tc.ed.NewEncoder(tc.conn)
 	err = enc.Encode(request)
 
@@ -72,8 +70,6 @@ func (tc *TCPConn) SendRequest(request *RPCRequest) (err error) {
 }
 
 func (tc *TCPConn) SendResponse(response *RPCResponse) (err error) {
-	err = nil
-
 	enc := tc.ed.NewEncoder(tc.conn)
 	err = enc.Encode(response)
 
@@ -91,3 +87,60 @@ func NewTCPConn(conn net.Conn, ed IEncoderDecoder) *TCPConn {
 
 	return ret
 }
+
+type NetHeartbeatConn struct {
+	sync.Mutex
+	conn io.ReadWriteCloser
+	dec  IDecoder
+	enc  IEncoder
+
+	// interfaces
+	IRPCConn
+}
+
+func (nhc *NetHeartbeatConn) ReceiveRequest() (ret *RPCRequest, err error) {
+	nhc.Lock()
+	defer nhc.Unlock()
+
+	ret = new(RPCRequest)
+	if err = nhc.dec.Decode(ret); err != nil {
+		return nil, err
+	}
+
+	return ret, err
+}
+
+func (nhc *NetHeartbeatConn) ReceiveResponse() (ret *RPCResponse, err error) {
+	nhc.Lock()
+	defer nhc.Unlock()
+
+	ret = new(RPCResponse)
+	if err = nhc.dec.Decode(ret); err != nil {
+		return nil, err
+	}
+
+	return ret, err
+}
+
+func (nhc *NetHeartbeatConn) SendRequest(request *RPCRequest) (err error) {
+	nhc.Lock()
+	defer nhc.Unlock()
+
+	err = nhc.enc.Encode(request)
+	return err
+}
+
+func (nhc *NetHeartbeatConn) SendResponse(response *RPCResponse) (err error) {
+	nhc.Lock()
+	defer nhc.Unlock()
+
+	err = nhc.enc.Encode(response)
+	return err
+}
+
+func (nhc *NetHeartbeatConn) Close() {
+	nhc.Lock()
+	defer nhc.Unlock()
+
+	nhc.conn.Close()
+}