diff --git a/go.mod b/go.mod
index 7f88823..f9567bd 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,6 @@ module git.noahlan.cn/northlan/nnet
 go 1.19
 
 require (
-	github.com/gorilla/websocket v1.5.0 // indirect
-	github.com/panjf2000/ants/v2 v2.6.0 // indirect
-	google.golang.org/protobuf v1.28.1 // indirect
+	github.com/gorilla/websocket v1.5.0
+	github.com/panjf2000/ants/v2 v2.6.0
 )
diff --git a/go.sum b/go.sum
index 7e0a492..d8816c7 100644
--- a/go.sum
+++ b/go.sum
@@ -1,10 +1,8 @@
-github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
-github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
 github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/panjf2000/ants/v2 v2.6.0 h1:xOSpw42m+BMiJ2I33we7h6fYzG4DAlpE1xyI7VS2gxU=
 github.com/panjf2000/ants/v2 v2.6.0/go.mod h1:cU93usDlihJZ5CfRGNDYsiBYvoilLvBF5Qp/BT2GNRE=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
-google.golang.org/protobuf v1.28.1 h1:d0NfwRgPtno5B1Wa6L2DAG+KivqkdutMf1UhdNx175w=
-google.golang.org/protobuf v1.28.1/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
+gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b h1:h8qDotaEPuJATrMmW04NCwg7v22aHH28wwpauUhK9Oo=
diff --git a/nnet/handler.go b/nnet/handler.go
index 7250120..a6f7d9e 100644
--- a/nnet/handler.go
+++ b/nnet/handler.go
@@ -45,5 +45,5 @@ func (h *Handler) register(comp component.Component, opts []component.Option) er
 }
 
 func (h *Handler) handle(request *Request) {
-
+	buf := make([]byte, 3)
 }
diff --git a/packet/packer.go b/packet/packer.go
new file mode 100644
index 0000000..d467d26
--- /dev/null
+++ b/packet/packer.go
@@ -0,0 +1,53 @@
+package packet
+
+type Packer interface {
+	// Pack 从原始raw bytes创建一个用于网络传输的 packet.Packet 结构
+	Pack(typ Type, data []byte) ([]byte, error)
+
+	// Unpack 解包
+	Unpack(data []byte) (*Packet, error)
+}
+
+type DefaultPacker struct {
+}
+
+// Codec constants.
+const (
+	headLength    = 4
+	maxPacketSize = 64 * 1024
+)
+
+func NewDefaultPacker() Packer {
+	return &DefaultPacker{}
+}
+
+func (d *DefaultPacker) Pack(typ Type, data []byte) ([]byte, error) {
+	if typ < Handshake || typ > Kick {
+		return nil, ErrWrongPacketType
+	}
+
+	p := &Packet{Type: typ, Length: uint32(len(data))}
+	buf := make([]byte, p.Length+headLength)
+
+	// header
+	buf[0] = byte(p.Type)
+	copy(buf[1:headLength], d.intToBytes(p.Length))
+
+	// body
+	copy(buf[headLength:], data)
+
+	return buf, nil
+}
+
+// Encode packet data length to bytes(Big end)
+func (d *DefaultPacker) intToBytes(n uint32) []byte {
+	buf := make([]byte, 3)
+	buf[0] = byte((n >> 16) & 0xFF)
+	buf[1] = byte((n >> 8) & 0xFF)
+	buf[2] = byte(n & 0xFF)
+	return buf
+}
+
+func (d *DefaultPacker) Unpack(data []byte) (*Packet, error) {
+	// header
+}
diff --git a/packet/packet.go b/packet/packet.go
index 8f2da8c..801501e 100644
--- a/packet/packet.go
+++ b/packet/packet.go
@@ -1,8 +1,6 @@
 package packet
 
-import (
-	"fmt"
-)
+import "errors"
 
 // Type 数据帧类型，如：握手，心跳，数据等
 type Type byte
@@ -27,14 +25,13 @@ const (
 	Kick = 0x05
 )
 
-type Packet struct {
-	Type Type // 数据帧 类型
-
-	HeaderLen uint32 // 数据帧头 长度
-	HeaderRaw []byte // 头原始数据
+// ErrWrongPacketType represents a wrong packet type.
+var ErrWrongPacketType = errors.New("wrong packet type")
 
-	DataLen uint32 // 数据长度
-	DataRaw []byte // 原始数据
+type Packet struct {
+	Type   Type   // 数据帧 类型
+	Length uint32 // 数据长度
+	Data   []byte // 原始数据
 }
 
 func New() *Packet {
@@ -42,7 +39,3 @@ func New() *Packet {
 		Type: Default,
 	}
 }
-
-func (p *Packet) String() string {
-	return fmt.Sprintf("Type: %d, HeaderLen: %d, DataLen: %d, Header: %s, Data: %s", p.Type, p.HeaderLen, p.DataLen, string(p.HeaderRaw), string(p.DataRaw))
-}
diff --git a/session/session.go b/session/session.go
index 7719ba1..2772b36 100644
--- a/session/session.go
+++ b/session/session.go
@@ -1,6 +1,7 @@
 package session
 
 import (
+	"git.noahlan.cn/northlan/nnet/nface"
 	"sync"
 	"sync/atomic"
 )