diff --git a/constant/metadata.go b/constant/metadata.go
index c0fe485..6399a41 100755
--- a/constant/metadata.go
+++ b/constant/metadata.go
@@ -87,7 +87,3 @@ func (m *Metadata) Network() string {
 func (m *Metadata) String() string {
 	return m.DestinationAddress()
 }
-
-func (m *Metadata) Valid() bool {
-	return m.SrcIP != nil && m.DstIP != nil
-}
diff --git a/tunnel/tcp.go b/tunnel/tcp.go
index 80e9499..a1f7aff 100755
--- a/tunnel/tcp.go
+++ b/tunnel/tcp.go
@@ -34,10 +34,6 @@ func handleTCP(localConn core.TCPConn) {
 		DstIP:   net.IP(id.LocalAddress),
 		DstPort: id.LocalPort,
 	}
-	if !metadata.Valid() {
-		log.Warnf("[Metadata] not valid: %#v", metadata)
-		return
-	}
 
 	targetConn, err := proxy.Dial(metadata)
 	if err != nil {
diff --git a/tunnel/udp.go b/tunnel/udp.go
index f54458b..d73a2f5 100755
--- a/tunnel/udp.go
+++ b/tunnel/udp.go
@@ -39,13 +39,9 @@ func handleUDP(packet core.UDPPacket) {
 		DstIP:   net.IP(id.LocalAddress),
 		DstPort: id.LocalPort,
 	}
-	if !metadata.Valid() {
-		log.Warnf("[Metadata] not valid: %#v", metadata)
-		return
-	}
 
 	generateNATKey := func(m *M.Metadata) string {
-		return m.SourceAddress() /* Full Cone NAT Key */
+		return m.SourceAddress() /* as Full Cone NAT Key */
 	}
 	key := generateNATKey(metadata)