diff --git a/CHANGELOG.md b/CHANGELOG.md
index b388e423..a596e75e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 ### CHANGES
 
 - `pkg/crypto/hashing`: doOnce encoding.HexEncode -> ToString method
+- `pkg/network/message`: delete GetRand, GetRandMessageSizeBytes
 
 <!-- ... -->
 
diff --git a/pkg/network/message/doc.go b/pkg/network/message/doc.go
index 8ee1dc3e..be2fba45 100644
--- a/pkg/network/message/doc.go
+++ b/pkg/network/message/doc.go
@@ -4,17 +4,15 @@
 /*
 	NETWORK MESSAGE FORMAT
 
-	E( K, P(HLMR) || HLMR || L(M) || M || L(R) || R )
+	E( K, P(HM) || HM || M )
 	where
-		HLMR = H( K, L(M) || M || L(R) || R )
+		HM = H( K, M )
 		where
 			H - HMAC
 			K - network key
 			M - message bytes
-			L - length
 			P - proof of work
 			E - encrypt
-			R - rand bytes
 
 	Scheme: https://github.com/number571/go-peer/blob/master/images/go-peer_layer1_net_message.jpg
 */
diff --git a/pkg/network/message/message.go b/pkg/network/message/message.go
index 54644a5d..bf8a4889 100644
--- a/pkg/network/message/message.go
+++ b/pkg/network/message/message.go
@@ -6,21 +6,18 @@ import (
 	"github.com/number571/go-peer/pkg/crypto/hashing"
 	"github.com/number571/go-peer/pkg/crypto/keybuilder"
 	"github.com/number571/go-peer/pkg/crypto/puzzle"
-	"github.com/number571/go-peer/pkg/crypto/random"
 	"github.com/number571/go-peer/pkg/crypto/symmetric"
 	"github.com/number571/go-peer/pkg/encoding"
 	"github.com/number571/go-peer/pkg/payload"
-	"github.com/number571/go-peer/pkg/payload/joiner"
 )
 
 const (
-	// IV + Proof + Hash + (2xPayload32Head)=[len(data)+len(void)] + Payload32Head=[head]
-	// 16 + 8 + 48 + 2x4 + 4 = 84 additional bytes to origin message
+	// IV + Proof + Hash + Payload32Head=[head]
+	// 16 + 8 + 48 + 4 = 76 additional bytes to origin message
 	CMessageHeadSize = 0 +
 		1*symmetric.CCipherBlockSize +
 		1*encoding.CSizeUint64 +
 		1*hashing.CHasherSize +
-		2*encoding.CSizeUint32 +
 		1*encoding.CSizeUint32
 )
 
@@ -34,23 +31,19 @@ var (
 )
 
 type sMessage struct {
-	fEncd    []byte             // E( K, P(HLMR) || HLMR || L(M) || M || L(R) || R )
-	fHash    []byte             // HLMR = H( K, L(M) || M || L(R) || R )
-	fRand    []byte             // R
-	fProof   uint64             // P(HLMR)
+	fEncd    []byte             // E( K, P(HM) || HM || M )
+	fHash    []byte             // HM = H( K, M )
+	fProof   uint64             // P(HM)
 	fPayload payload.IPayload32 // M
 }
 
 func NewMessage(pSett IConstructSettings, pPld payload.IPayload32) IMessage {
-	prng := random.NewRandom()
 	sett := pSett.GetSettings()
-
-	randBytes := prng.GetBytes(prng.GetUint64() % (pSett.GetRandMessageSizeBytes() + 1))
-	bytesJoiner := joiner.NewBytesJoiner32([][]byte{pPld.ToBytes(), randBytes})
+	pldBytes := pPld.ToBytes()
 
 	keyBuilder := keybuilder.NewKeyBuilder(0, []byte{}) // the network_key must have good entropy
 	key := keyBuilder.Build(sett.GetNetworkKey(), symmetric.CCipherKeySize)
-	hash := hashing.NewHMACHasher(key, bytesJoiner).ToBytes()
+	hash := hashing.NewHMACHasher(key, pldBytes).ToBytes()
 
 	proof := puzzle.NewPoWPuzzle(sett.GetWorkSizeBits()).ProofBytes(hash, pSett.GetParallel())
 	proofBytes := encoding.Uint64ToBytes(proof)
@@ -61,12 +54,11 @@ func NewMessage(pSett IConstructSettings, pPld payload.IPayload32) IMessage {
 			[][]byte{
 				proofBytes[:],
 				hash,
-				bytesJoiner,
+				pldBytes,
 			},
 			[]byte{},
 		)),
 		fHash:    hash,
-		fRand:    randBytes,
 		fProof:   proof,
 		fPayload: pPld,
 	}
@@ -102,17 +94,12 @@ func LoadMessage(pSett ISettings, pData interface{}) (IMessage, error) {
 		return nil, ErrInvalidProofOfWork
 	}
 
-	bytesSlice, err := joiner.LoadBytesJoiner32(dBytes[cHashIndex:])
-	if err != nil || len(bytesSlice) != 2 {
-		return nil, ErrDecodeBytesJoiner
-	}
-
 	newHash := hashing.NewHMACHasher(key, dBytes[cHashIndex:]).ToBytes()
 	if !bytes.Equal(hash, newHash) {
 		return nil, ErrInvalidAuthHash
 	}
 
-	payload := payload.LoadPayload32(bytesSlice[0])
+	payload := payload.LoadPayload32(dBytes[cHashIndex:])
 	if payload == nil {
 		return nil, ErrDecodePayload
 	}
@@ -120,7 +107,6 @@ func LoadMessage(pSett ISettings, pData interface{}) (IMessage, error) {
 	return &sMessage{
 		fEncd:    msgBytes,
 		fHash:    hash,
-		fRand:    bytesSlice[1],
 		fProof:   proof,
 		fPayload: payload,
 	}, nil
@@ -134,10 +120,6 @@ func (p *sMessage) GetHash() []byte {
 	return p.fHash
 }
 
-func (p *sMessage) GetRand() []byte {
-	return p.fRand
-}
-
 func (p *sMessage) GetPayload() payload.IPayload32 {
 	return p.fPayload
 }
diff --git a/pkg/network/message/message_test.go b/pkg/network/message/message_test.go
index bbbe0b69..32b7368e 100644
--- a/pkg/network/message/message_test.go
+++ b/pkg/network/message/message_test.go
@@ -11,7 +11,6 @@ import (
 	"github.com/number571/go-peer/pkg/crypto/symmetric"
 	"github.com/number571/go-peer/pkg/encoding"
 	"github.com/number571/go-peer/pkg/payload"
-	"github.com/number571/go-peer/pkg/payload/joiner"
 )
 
 var (
@@ -101,32 +100,9 @@ func TestMessage(t *testing.T) {
 		return
 	}
 
-	voidBytes := msg.GetRand()
-	if len(voidBytes) > tcLimitVoid {
-		t.Error("got length void bytes > limit")
-		return
-	}
-
-	if (len(msg.ToBytes()) - len(voidBytes)) != len(msg.GetPayload().GetBody())+CMessageHeadSize {
-		t.Error("invalid message size in bytes with void")
-		return
-	}
-
-	payloadSize := encoding.Uint32ToBytes(uint32(len(pld.ToBytes())))
-	voidSize := encoding.Uint32ToBytes(uint32(len(voidBytes)))
-	payloadRandBytes := bytes.Join(
-		[][]byte{
-			payloadSize[:],
-			pld.ToBytes(),
-			voidSize[:],
-			voidBytes,
-		},
-		[]byte{},
-	)
-
 	keyBuilder := keybuilder.NewKeyBuilder(0, []byte{}) // the network_key must have good entropy
 	key := keyBuilder.Build(tcNetworkKey, symmetric.CCipherKeySize)
-	newHash := hashing.NewHMACHasher(key, payloadRandBytes).ToBytes()
+	newHash := hashing.NewHMACHasher(key, pld.ToBytes()).ToBytes()
 	if !bytes.Equal(msg.GetHash(), newHash) {
 		t.Error("payload hash not equal hash of message")
 		return
@@ -244,46 +220,12 @@ func TestMessage(t *testing.T) {
 		t.Error("success load invalid message 2")
 		return
 	}
-
-	if _, err := LoadMessage(sett.GetSettings(), tNewInvalidMessage3(sett, pld).ToBytes()); err == nil {
-		t.Error("success load invalid message 3")
-		return
-	}
 }
 
 func tNewInvalidMessage1(pSett IConstructSettings, pPld payload.IPayload32) IMessage {
-	bytesJoiner := joiner.NewBytesJoiner32([][]byte{pPld.ToBytes()})
 	sett := pSett.GetSettings()
 
-	keyBuilder := keybuilder.NewKeyBuilder(0, []byte{}) // the network_key must have good entropy
-	key := keyBuilder.Build(tcNetworkKey, symmetric.CCipherKeySize)
-	hash := hashing.NewHMACHasher(key, bytesJoiner).ToBytes()
-
-	proof := puzzle.NewPoWPuzzle(sett.GetWorkSizeBits()).ProofBytes(hash, pSett.GetParallel())
-	proofBytes := encoding.Uint64ToBytes(proof)
-
-	cipher := symmetric.NewCipher(key)
-	return &sMessage{
-		fEncd: cipher.EncryptBytes(bytes.Join(
-			[][]byte{
-				proofBytes[:],
-				hash,
-				bytesJoiner,
-			},
-			[]byte{},
-		)),
-		fHash:    hash,
-		fProof:   proof,
-		fPayload: pPld,
-	}
-}
-
-func tNewInvalidMessage2(pSett IConstructSettings, pPld payload.IPayload32) IMessage {
-	prng := random.NewRandom()
-	sett := pSett.GetSettings()
-
-	voidBytes := prng.GetBytes(prng.GetUint64() % (pSett.GetRandMessageSizeBytes() + 1))
-	bytesJoiner := joiner.NewBytesJoiner32([][]byte{pPld.ToBytes(), voidBytes})
+	bytesJoiner := pPld.ToBytes()
 
 	keyBuilder := keybuilder.NewKeyBuilder(0, []byte{}) // the network_key must have good entropy
 	key := keyBuilder.Build(tcNetworkKey, symmetric.CCipherKeySize)
@@ -305,18 +247,15 @@ func tNewInvalidMessage2(pSett IConstructSettings, pPld payload.IPayload32) IMes
 			[]byte{},
 		)),
 		fHash:    hash,
-		fRand:    voidBytes,
 		fProof:   proof,
 		fPayload: pPld,
 	}
 }
 
-func tNewInvalidMessage3(pSett IConstructSettings, pPld payload.IPayload32) IMessage {
-	prng := random.NewRandom()
+func tNewInvalidMessage2(pSett IConstructSettings, pPld payload.IPayload32) IMessage {
 	sett := pSett.GetSettings()
 
-	voidBytes := prng.GetBytes(prng.GetUint64() % (pSett.GetRandMessageSizeBytes() + 1))
-	bytesJoiner := joiner.NewBytesJoiner32([][]byte{nil, voidBytes})
+	bytesJoiner := []byte{}
 
 	keyBuilder := keybuilder.NewKeyBuilder(0, []byte{}) // the network_key must have good entropy
 	key := keyBuilder.Build(tcNetworkKey, symmetric.CCipherKeySize)
@@ -336,7 +275,6 @@ func tNewInvalidMessage3(pSett IConstructSettings, pPld payload.IPayload32) IMes
 			[]byte{},
 		)),
 		fHash:    hash,
-		fRand:    voidBytes,
 		fProof:   proof,
 		fPayload: pPld,
 	}
diff --git a/pkg/network/message/types.go b/pkg/network/message/types.go
index f98ed50d..80a89b0a 100644
--- a/pkg/network/message/types.go
+++ b/pkg/network/message/types.go
@@ -9,7 +9,6 @@ type IMessage interface {
 	types.IConverter
 
 	GetHash() []byte
-	GetRand() []byte
 	GetProof() uint64
 
 	// payload = head(32bit) || body(Nbit)
@@ -19,7 +18,6 @@ type IMessage interface {
 type IConstructSettings interface {
 	GetSettings() ISettings
 	GetParallel() uint64
-	GetRandMessageSizeBytes() uint64
 }
 
 type ISettings interface {