diff --git a/brontide/noise.go b/brontide/noise.go
index fdf91924..5a314404 100644
--- a/brontide/noise.go
+++ b/brontide/noise.go
@@ -4,7 +4,9 @@ import (
 	"crypto/cipher"
 	"crypto/sha256"
 	"encoding/binary"
+	"errors"
 	"io"
+	"math"
 
 	"golang.org/x/crypto/hkdf"
 
@@ -19,6 +21,18 @@ const (
 	// exact same string for this value, along with prologue of the Bitcoin
 	// network, then the initial handshake will fail.
 	protocolName = "Noise_XK_secp256k1_ChaChaPoly_SHA256"
+
+	// macSize is the length in bytes of the tags generated by poly1305.
+	macSize = 16
+
+	// lengthHeaderSize is the number of bytes used to prefix encode the
+	// length of a message payload.
+	lengthHeaderSize = 2
+)
+
+var (
+	ErrMaxMessageLengthExceeded = errors.New("the generated payload exceeds " +
+		"the max allowed message length of (2^16)-1")
 )
 
 // TODO(roasbeef): free buffer pool?
@@ -533,12 +547,18 @@ func (b *BrontideMachine) split() {
 // must be used as the AD to the AEAD construction when being decrypted by the
 // other side.
 func (b *BrontideMachine) WriteMessage(w io.Writer, p []byte) error {
-	// The full length of the packet includes the 16 byte MAC.
-	fullLength := uint64(len(p) + 16)
+	// The total length of each message payload including the MAC size
+	// payload exceed the largest number encodable within a 16-bit unsigned
+	// integer.
+	if len(p)+macSize > math.MaxUint16 {
+		return ErrMaxMessageLengthExceeded
+	}
 
-	// TODO(roasbeef): The Summit decided on 24 bits?
-	var pktLen [8]byte
-	binary.BigEndian.PutUint64(pktLen[:], fullLength)
+	// The full length of the packet includes the 16 byte MAC.
+	fullLength := uint16(len(p) + macSize)
+
+	var pktLen [2]byte
+	binary.BigEndian.PutUint16(pktLen[:], fullLength)
 
 	// First, write out the encrypted+MAC'd length prefix for the packet.
 	cipherLen := b.sendCipher.Encrypt(nil, nil, pktLen[:])
@@ -560,7 +580,7 @@ func (b *BrontideMachine) WriteMessage(w io.Writer, p []byte) error {
 // ReadMessage attemps to read the next message from the passed io.Reader. In
 // the case of an authentication error, a non-nil error is returned.
 func (b *BrontideMachine) ReadMessage(r io.Reader) ([]byte, error) {
-	var cipherLen [8 + 16]byte
+	var cipherLen [lengthHeaderSize + macSize]byte
 	if _, err := io.ReadFull(r, cipherLen[:]); err != nil {
 		return nil, err
 	}
@@ -573,7 +593,7 @@ func (b *BrontideMachine) ReadMessage(r io.Reader) ([]byte, error) {
 
 	// Next, using the length read from the packet header, read the
 	// encrypted packet itself.
-	pktLen := binary.BigEndian.Uint64(pktLenBytes)
+	pktLen := binary.BigEndian.Uint16(pktLenBytes)
 	ciperText := make([]byte, pktLen)
 	if _, err := io.ReadFull(r, ciperText[:]); err != nil {
 		return nil, err
diff --git a/brontide/noise_test.go b/brontide/noise_test.go
index ad1507ba..cf3f1ac2 100644
--- a/brontide/noise_test.go
+++ b/brontide/noise_test.go
@@ -2,6 +2,7 @@ package brontide
 
 import (
 	"bytes"
+	"math"
 	"net"
 	"testing"
 
@@ -97,6 +98,44 @@ func TestConnectionCorrectness(t *testing.T) {
 	}
 }
 
+func TestMaxPayloadLength(t *testing.T) {
+	b := BrontideMachine{}
+	b.split()
+
+	// Create a payload that's juust over the maximum alloted payload
+	// length.
+	payloadToReject := make([]byte, math.MaxUint16+1)
+
+	var buf bytes.Buffer
+
+	// A write of the payload generated above to the state machine should
+	// be rejected as it's over the max payload length.
+	err := b.WriteMessage(&buf, payloadToReject)
+	if err != ErrMaxMessageLengthExceeded {
+		t.Fatalf("payload is over the max allowed length, the write " +
+			"should have been rejected")
+	}
+
+	// Generate another payload which with the MAC acounted for, should be
+	// accepted as a valid payload.
+	payloadToAccept := make([]byte, math.MaxUint16-macSize)
+	if err := b.WriteMessage(&buf, payloadToAccept); err != nil {
+		t.Fatalf("write for payload was rejected, should have been " +
+			"accepted")
+	}
+
+	// Generate a final payload which is juuust over the max payload length
+	// when the MAC is accounted for.
+	payloadToReject = make([]byte, math.MaxUint16-macSize+1)
+
+	// This payload should be rejected.
+	err = b.WriteMessage(&buf, payloadToReject)
+	if err != ErrMaxMessageLengthExceeded {
+		t.Fatalf("payload is over the max allowed length, the write " +
+			"should have been rejected")
+	}
+}
+
 func TestNoiseIdentityHiding(t *testing.T) {
 	// TODO(roasbeef): fin
 }