diff --git a/common/bufio/conn.go b/common/bufio/conn.go
index ffa83ea..fa5d157 100644
--- a/common/bufio/conn.go
+++ b/common/bufio/conn.go
@@ -354,7 +354,7 @@ func (w *ExtendedUDPConn) ReadPacket(buffer *buf.Buffer) (M.Socksaddr, error) {
 
 func (w *ExtendedUDPConn) WritePacket(buffer *buf.Buffer, destination M.Socksaddr) error {
 	defer buffer.Release()
-	if destination.Family().IsFqdn() {
+	if destination.IsFqdn() {
 		udpAddr, err := net.ResolveUDPAddr("udp", destination.String())
 		if err != nil {
 			return err
diff --git a/common/metadata/addr.go b/common/metadata/addr.go
index f1a2b57..eb17a95 100644
--- a/common/metadata/addr.go
+++ b/common/metadata/addr.go
@@ -4,12 +4,13 @@ import (
 	"net"
 	"net/netip"
 	"strconv"
+	"unsafe"
 )
 
 type Socksaddr struct {
 	Addr netip.Addr
-	Fqdn string
 	Port uint16
+	Fqdn string
 }
 
 func (ap Socksaddr) Network() string {
@@ -20,25 +21,22 @@ func (ap Socksaddr) IsIP() bool {
 	return ap.Addr.IsValid()
 }
 
+func (ap Socksaddr) IsIPv4() bool {
+	return ap.Addr.Is4()
+}
+
+func (ap Socksaddr) IsIPv6() bool {
+	return ap.Addr.Is6()
+}
+
 func (ap Socksaddr) IsFqdn() bool {
-	return !ap.IsIP()
+	return !ap.Addr.IsValid()
 }
 
 func (ap Socksaddr) IsValid() bool {
 	return ap.Addr.IsValid() || ap.Fqdn != ""
 }
 
-func (ap Socksaddr) Family() Family {
-	if ap.Addr.IsValid() {
-		if ap.Addr.Is4() || ap.Addr.Is4In6() {
-			return AddressFamilyIPv4
-		} else {
-			return AddressFamilyIPv6
-		}
-	}
-	return AddressFamilyFqdn
-}
-
 func (ap Socksaddr) AddrString() string {
 	if ap.Addr.IsValid() {
 		return ap.Addr.String()
@@ -68,7 +66,7 @@ func (ap Socksaddr) UDPAddr() *net.UDPAddr {
 }
 
 func (ap Socksaddr) AddrPort() netip.AddrPort {
-	return netip.AddrPortFrom(ap.Addr, ap.Port)
+	return *(*netip.AddrPort)(unsafe.Pointer(&ap))
 }
 
 func (ap Socksaddr) String() string {
diff --git a/common/metadata/family.go b/common/metadata/family.go
index 80011ee..c6551c2 100644
--- a/common/metadata/family.go
+++ b/common/metadata/family.go
@@ -1,27 +1,9 @@
 package metadata
 
-type Family byte
+type Family = byte
 
 const (
-	AddressFamilyIPv4 Family = iota
-	AddressFamilyIPv6
-	AddressFamilyFqdn
+	AddressFamilyIPv4 Family = 0x01
+	AddressFamilyIPv6 Family = 0x04
+	AddressFamilyFqdn Family = 0x03
 )
-
-func (af Family) IsIPv4() bool {
-	return af == AddressFamilyIPv4
-}
-
-func (af Family) IsIPv6() bool {
-	return af == AddressFamilyIPv6
-}
-
-func (af Family) IsIP() bool {
-	return af != AddressFamilyFqdn
-}
-
-func (af Family) IsFqdn() bool {
-	return af == AddressFamilyFqdn
-}
-
-type FamilyParser func(byte) byte
diff --git a/common/metadata/network.go b/common/metadata/network.go
index df5f319..c171f7c 100644
--- a/common/metadata/network.go
+++ b/common/metadata/network.go
@@ -3,7 +3,7 @@ package metadata
 import "net/netip"
 
 func NetworkFromNetAddr(network string, addr netip.Addr) string {
-	if addr.Is4() && (addr.IsUnspecified() || addr.IsGlobalUnicast() || addr.IsLinkLocalUnicast()) {
+	if addr == netip.IPv4Unspecified() {
 		return network + "4"
 	}
 	return network
diff --git a/common/metadata/serializer.go b/common/metadata/serializer.go
index 4c3dc37..1e7f934 100644
--- a/common/metadata/serializer.go
+++ b/common/metadata/serializer.go
@@ -43,7 +43,15 @@ func NewSerializer(options ...SerializerOption) *Serializer {
 }
 
 func (s *Serializer) WriteAddress(writer io.Writer, addr Socksaddr) error {
-	err := rw.WriteByte(writer, s.familyByteMap[addr.Family()])
+	var family Family
+	if addr.IsIPv4() {
+		family = AddressFamilyIPv4
+	} else if addr.IsIPv6() {
+		family = AddressFamilyIPv6
+	} else {
+		family = AddressFamilyFqdn
+	}
+	err := rw.WriteByte(writer, family)
 	if err != nil {
 		return err
 	}
@@ -56,12 +64,11 @@ func (s *Serializer) WriteAddress(writer io.Writer, addr Socksaddr) error {
 }
 
 func (s *Serializer) AddressLen(addr Socksaddr) int {
-	switch addr.Family() {
-	case AddressFamilyIPv4:
+	if addr.IsIPv4() {
 		return 5
-	case AddressFamilyIPv6:
+	} else if addr.IsIPv6() {
 		return 17
-	default:
+	} else {
 		return 2 + len(addr.Fqdn)
 	}
 }
diff --git a/common/uot/server.go b/common/uot/server.go
index f5ff4e8..efd0c6e 100644
--- a/common/uot/server.go
+++ b/common/uot/server.go
@@ -54,7 +54,7 @@ func (c *ServerConn) loopInput() {
 		if err != nil {
 			break
 		}
-		if destination.Family().IsFqdn() {
+		if destination.IsFqdn() {
 			addr, err := net.ResolveUDPAddr("udp", destination.String())
 			if err != nil {
 				continue
diff --git a/protocol/socks/client.go b/protocol/socks/client.go
index 82b6a10..8ac7ab8 100644
--- a/protocol/socks/client.go
+++ b/protocol/socks/client.go
@@ -113,7 +113,7 @@ func (c *Client) DialContext(ctx context.Context, network string, address M.Sock
 	if err != nil {
 		return nil, err
 	}
-	if c.version == Version4 && address.Family().IsFqdn() {
+	if c.version == Version4 && address.IsFqdn() {
 		tcpAddr, err := net.ResolveTCPAddr(network, address.String())
 		if err != nil {
 			tcpConn.Close()
diff --git a/protocol/socks/handshake.go b/protocol/socks/handshake.go
index 6cc891d..5908a59 100644
--- a/protocol/socks/handshake.go
+++ b/protocol/socks/handshake.go
@@ -111,7 +111,7 @@ func HandleConnection0(ctx context.Context, conn net.Conn, version byte, authent
 		switch request.Command {
 		case socks4.CommandConnect:
 			responseAddr := request.Destination
-			if !responseAddr.Family().IsIPv4() {
+			if !responseAddr.IsIPv4() {
 				responseAddr = M.SocksaddrFromAddrPort(netip.IPv4Unspecified(), responseAddr.Port)
 			}
 			err = socks4.WriteResponse(conn, socks4.Response{
diff --git a/protocol/socks/socks4/protocol.go b/protocol/socks/socks4/protocol.go
index 6d7fc8a..23d507b 100644
--- a/protocol/socks/socks4/protocol.go
+++ b/protocol/socks/socks4/protocol.go
@@ -81,7 +81,7 @@ func WriteRequest(writer io.Writer, request Request) error {
 	if err != nil {
 		return err
 	}
-	if request.Destination.Family().IsIPv4() {
+	if request.Destination.IsIPv4() {
 		dstIP := request.Destination.Addr.As4()
 		_, err = writer.Write(dstIP[:])
 		if err != nil {