diff --git a/core/engine/conn.go b/core/engine/conn.go
new file mode 100644
index 0000000..bbca5ed
--- /dev/null
+++ b/core/engine/conn.go
@@ -0,0 +1,117 @@
+package engine
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/netip"
+
+	"github.com/libp2p/go-libp2p/core/network"
+	"github.com/libp2p/go-libp2p/core/peer"
+	"github.com/mr-tron/base58/base58"
+	"go4.org/netipx"
+)
+
+func (e *Engine) addConnByDst(dst netip.Addr) (PacketChan, error) {
+	e.log.Debugf(e.ctx, "Try to connect to the corresponding node of %s", dst)
+
+	var conn PacketChan
+	e.routeTable.set.Range(func(id peer.ID, prefix *netipx.IPSet) bool {
+		if !prefix.Contains(dst) {
+			return true
+		}
+
+		if c, ok := e.routeTable.id.Load(id); ok {
+			conn = c
+			e.routeTable.addr.Store(dst, c)
+			return false
+		}
+		peerChan := make(chan Payload, ChanSize)
+		conn = peerChan
+		e.routeTable.addr.Store(dst, peerChan)
+
+		go func() {
+			defer e.routeTable.addr.Delete(dst)
+			e.addConn(peerChan, id)
+		}()
+		return false
+	})
+
+	if conn != nil {
+		return conn, nil
+	}
+
+	return nil, errors.New(fmt.Sprintf("unknown dst addr: %s", dst.String()))
+}
+
+func (e *Engine) addConnByID(id peer.ID) (PacketChan, error) {
+	e.log.Debugf(e.ctx, "Try to connect to the corresponding node of %s", string(id))
+
+	if conn, ok := e.routeTable.id.Load(id); ok {
+		return conn, nil
+	}
+
+	peerChan := make(chan Payload, ChanSize)
+	e.routeTable.id.Store(id, peerChan)
+
+	go func() {
+		defer e.routeTable.id.Delete(id)
+		e.addConn(peerChan, id)
+	}()
+
+	return nil, errors.New(fmt.Sprintf("unknown dst addr: %s", string(id)))
+}
+
+func (e *Engine) addConn(peerChan PacketChan, id peer.ID) {
+	dev := &devWrapper{w: e.devWriter, r: peerChan}
+	e.log.Infof(e.ctx, "start find peer %s", string(id))
+
+	var (
+		stream network.Stream
+		err    error
+	)
+
+	idr, err := base58.Decode(string(id))
+	if err != nil {
+		e.log.Infof(e.ctx, "base58 decode failed: %s", err)
+	}
+
+	info := e.host.Peerstore().PeerInfo(peer.ID(idr))
+	if len(info.Addrs) > 0 {
+		stream, err = e.host.NewStream(e.ctx, info.ID, VPNStreamProtocol)
+		if err != nil {
+			peerc, err := e.discovery.FindPeers(e.ctx, string(id))
+			if err != nil {
+				e.log.Warningf(e.ctx, "Finding node by dht %s failed because %s", string(id), err)
+				return
+			}
+
+			for info := range peerc {
+				if info.ID.String() == string(id) && len(info.Addrs) > 0 {
+					stream, err = e.host.NewStream(e.ctx, info.ID, VPNStreamProtocol)
+					if err == nil {
+						break
+					}
+				}
+			}
+			e.log.Warningf(e.ctx, "Connection establishment with node %s failed", string(id))
+			return
+		}
+	}
+
+	e.log.Infof(e.ctx, "Peer [%s] connect success", string(id))
+	defer stream.Close()
+
+	go func() {
+		defer stream.Close()
+		_, err := io.Copy(stream, dev)
+		if err != nil && err != io.EOF {
+			e.log.Errorf(e.ctx, "Peer [%s] stream write error: %s", string(id), err)
+		}
+	}()
+
+	_, err = io.Copy(dev, stream)
+	if err != nil && err != io.EOF {
+		e.log.Errorf(e.ctx, "Peer [%s] stream read error: %s", string(id), err)
+	}
+}
diff --git a/core/engine/engine.go b/core/engine/engine.go
index b692639..e9a8847 100644
--- a/core/engine/engine.go
+++ b/core/engine/engine.go
@@ -5,7 +5,6 @@ import (
 	"NetHive/core/protocol"
 	"NetHive/pkgs/xsync"
 	"context"
-	"errors"
 	"fmt"
 	"io"
 	"net/netip"
@@ -21,7 +20,6 @@ import (
 	"github.com/libp2p/go-libp2p/p2p/discovery/mdns"
 	"github.com/libp2p/go-libp2p/p2p/discovery/routing"
 	"github.com/libp2p/go-libp2p/p2p/discovery/util"
-	"github.com/mr-tron/base58"
 	"go4.org/netipx"
 )
 
@@ -272,105 +270,54 @@ func (e *Engine) RoutineRouteTableWriter() {
 
 	for payload = range e.devReader {
 		var conn PacketChan
-		c, ok := e.routeTable.addr.Load(payload.Dst)
-		if ok {
-			conn = c
-		} else {
-			c, err := e.addConn(payload.Dst)
-			if err != nil {
-				e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because %s", payload.Dst, err)
-				continue
-			}
-			conn = c
-		}
 
-		select {
-		case conn <- payload:
-		default:
-			e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because the sending queue is already full", payload.Dst)
-		}
-	}
-}
+		if payload.Dst.IsMulticast() {
+			e.routeTable.m.Range(func(key peer.ID, value []netip.Prefix) bool {
+				if key == peer.ID(e.host.ID().String()) {
+					return true
+				}
 
-func (e *Engine) addConn(dst netip.Addr) (PacketChan, error) {
-	e.log.Debugf(e.ctx, "Try to connect to the corresponding node of %s", dst)
+				if conn, ok := e.routeTable.id.Load(key); ok {
+					select {
+					case conn <- payload:
+					default:
+						e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because the sending queue is already full", payload.Dst)
+					}
+					return true
+				}
 
-	var conn PacketChan
-	e.routeTable.set.Range(func(id peer.ID, prefix *netipx.IPSet) bool {
-		if !prefix.Contains(dst) {
-			return true
-		}
-
-		if c, ok := e.routeTable.id.Load(id); ok {
-			conn = c
-			e.routeTable.addr.Store(dst, c)
-			return false
-		}
-		peerChan := make(chan Payload, ChanSize)
-		conn = peerChan
-		e.routeTable.addr.Store(dst, peerChan)
-
-		go func() {
-			defer e.routeTable.addr.Delete(dst)
-
-			dev := &devWrapper{w: e.devWriter, r: peerChan}
-			e.log.Infof(e.ctx, "start find peer %s", string(id))
-
-			var (
-				stream network.Stream
-				err    error
-			)
-
-			idr, err := base58.Decode(string(id))
-			if err != nil {
-				e.log.Infof(e.ctx, "base58 decode failed: %s", err)
-			}
-
-			info := e.host.Peerstore().PeerInfo(peer.ID(idr))
-			if len(info.Addrs) > 0 {
-				stream, err = e.host.NewStream(e.ctx, info.ID, VPNStreamProtocol)
+				conn, err := e.addConnByID(key)
 				if err != nil {
-					peerc, err := e.discovery.FindPeers(e.ctx, string(id))
-					if err != nil {
-						e.log.Warningf(e.ctx, "Finding node by dht %s failed because %s", string(id), err)
-						return
-					}
-
-					for info := range peerc {
-						if info.ID.String() == string(id) && len(info.Addrs) > 0 {
-							stream, err = e.host.NewStream(e.ctx, info.ID, VPNStreamProtocol)
-							if err == nil {
-								break
-							}
-						}
-					}
-					e.log.Warningf(e.ctx, "Connection establishment with node %s failed", string(id))
-					return
+					e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because %s", payload.Dst, err)
+					return true
 				}
+
+				select {
+				case conn <- payload:
+				default:
+					e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because the sending queue is already full", payload.Dst)
+				}
+
+				return true
+			})
+		} else {
+			c, ok := e.routeTable.addr.Load(payload.Dst)
+			if ok {
+				conn = c
+			} else {
+				c, err := e.addConnByDst(payload.Dst)
+				if err != nil {
+					e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because %s", payload.Dst, err)
+					continue
+				}
+				conn = c
 			}
 
-			e.log.Infof(e.ctx, "Peer [%s] connect success", string(id))
-			defer stream.Close()
-
-			go func() {
-				defer stream.Close()
-				_, err := io.Copy(stream, dev)
-				if err != nil && err != io.EOF {
-					e.log.Errorf(e.ctx, "Peer [%s] stream write error: %s", string(id), err)
-				}
-			}()
-
-			_, err = io.Copy(dev, stream)
-			if err != nil && err != io.EOF {
-				e.log.Errorf(e.ctx, "Peer [%s] stream read error: %s", string(id), err)
+			select {
+			case conn <- payload:
+			default:
+				e.log.Warningf(e.ctx, "[RoutineRouteTableWriter] drop packet: %s, because the sending queue is already full", payload.Dst)
 			}
-		}()
-		return false
-	})
-
-	if conn != nil {
-		return conn, nil
+		}
 	}
-
-	return nil, errors.New(fmt.Sprintf("unknown dst addr: %s", dst.String()))
 }