diff --git a/common/net/address.go b/common/net/address.go
index f041c95c..5032f9dc 100644
--- a/common/net/address.go
+++ b/common/net/address.go
@@ -3,66 +3,142 @@ package net
 import (
 	"net"
 	"strconv"
+
+	"github.com/v2ray/v2ray-core/common/log"
 )
 
-const (
-	AddrTypeIP     = byte(0x01)
-	AddrTypeDomain = byte(0x03)
-)
+type Address interface {
+	IP() net.IP
+	Domain() string
+	Port() uint16
+	PortBytes() []byte
 
-type Address struct {
-	Type   byte
-	IP     net.IP
-	Domain string
-	Port   uint16
+	IsIPv4() bool
+	IsIPv6() bool
+	IsDomain() bool
+
+	String() string
 }
 
 func IPAddress(ip []byte, port uint16) Address {
-	ipCopy := make([]byte, len(ip))
-	copy(ipCopy, ip)
-	// TODO: check IP length
-	return Address{
-		Type:   AddrTypeIP,
-		IP:     net.IP(ipCopy),
-		Domain: "",
-		Port:   port,
+	switch len(ip) {
+	case net.IPv4len:
+		return IPv4Address{
+			PortAddress: PortAddress{port: port},
+			ip:          [4]byte{ip[0], ip[1], ip[2], ip[3]},
+		}
+	case net.IPv6len:
+		return IPv6Address{
+			PortAddress: PortAddress{port: port},
+			ip:          [16]byte{ip[0], ip[1], ip[2], ip[3], ip[4], ip[5], ip[6], ip[7], ip[8], ip[9], ip[10], ip[11], ip[12], ip[13], ip[14], ip[15]},
+		}
+	default:
+		panic(log.Error("Unknown IP format: %v", ip))
 	}
 }
 
 func DomainAddress(domain string, port uint16) Address {
-	return Address{
-		Type:   AddrTypeDomain,
-		IP:     nil,
-		Domain: domain,
-		Port:   port,
+	return DomainAddressImpl{
+		domain:      domain,
+		PortAddress: PortAddress{port: port},
 	}
 }
 
-func (addr Address) IsIPv4() bool {
-	return addr.Type == AddrTypeIP && len(addr.IP) == net.IPv4len
+type PortAddress struct {
+	port uint16
 }
 
-func (addr Address) IsIPv6() bool {
-	return addr.Type == AddrTypeIP && len(addr.IP) == net.IPv6len
+func (addr PortAddress) Port() uint16 {
+	return addr.port
 }
 
-func (addr Address) IsDomain() bool {
-	return addr.Type == AddrTypeDomain
+func (addr PortAddress) PortBytes() []byte {
+	return []byte{byte(addr.port >> 8), byte(addr.port)}
 }
 
-func (addr Address) String() string {
-	var host string
-	switch addr.Type {
-	case AddrTypeIP:
-		host = addr.IP.String()
-		if len(addr.IP) == net.IPv6len {
-			host = "[" + host + "]"
-		}
-
-	case AddrTypeDomain:
-		host = addr.Domain
-	default:
-		panic("Unknown Address Type " + strconv.Itoa(int(addr.Type)))
-	}
-	return host + ":" + strconv.Itoa(int(addr.Port))
+type IPv4Address struct {
+	PortAddress
+	ip [4]byte
+}
+
+func (addr IPv4Address) IP() net.IP {
+	return net.IP(addr.ip[:])
+}
+
+func (addr IPv4Address) Domain() string {
+	panic("Calling Domain() on an IPv4Address.")
+}
+
+func (addr IPv4Address) IsIPv4() bool {
+	return true
+}
+
+func (addr IPv4Address) IsIPv6() bool {
+	return false
+}
+
+func (addr IPv4Address) IsDomain() bool {
+	return false
+}
+
+func (addr IPv4Address) String() string {
+	return addr.IP().String() + ":" + strconv.Itoa(int(addr.PortAddress.port))
+}
+
+type IPv6Address struct {
+	PortAddress
+	ip [16]byte
+}
+
+func (addr IPv6Address) IP() net.IP {
+	return net.IP(addr.ip[:])
+}
+
+func (addr IPv6Address) Domain() string {
+	panic("Calling Domain() on an IPv6Address.")
+}
+
+func (addr IPv6Address) IsIPv4() bool {
+	return false
+}
+
+func (addr IPv6Address) IsIPv6() bool {
+	return true
+}
+
+func (addr IPv6Address) IsDomain() bool {
+	return false
+}
+
+func (addr IPv6Address) String() string {
+	return "[" + addr.IP().String() + "]:" + strconv.Itoa(int(addr.PortAddress.port))
+}
+
+type DomainAddressImpl struct {
+	PortAddress
+	domain string
+}
+
+func (addr DomainAddressImpl) IP() net.IP {
+	panic("Calling IP() on a DomainAddress.")
+}
+
+func (addr DomainAddressImpl) Domain() string {
+	return addr.domain
+}
+
+func (addr DomainAddressImpl) IsIPv4() bool {
+	return false
+}
+
+func (addr DomainAddressImpl) IsIPv6() bool {
+	return false
+}
+
+func (addr DomainAddressImpl) IsDomain() bool {
+	return true
+}
+
+func (addr DomainAddressImpl) String() string {
+	return addr.domain + ":" + strconv.Itoa(int(addr.PortAddress.port))
 }
diff --git a/common/net/address_test.go b/common/net/address_test.go
index f8af392c..9ddeb6f7 100644
--- a/common/net/address_test.go
+++ b/common/net/address_test.go
@@ -13,10 +13,9 @@ func TestIPv4Address(t *testing.T) {
 	port := uint16(80)
 	addr := IPAddress(ip, port)
 
-	assert.Byte(addr.Type).Equals(AddrTypeIP)
 	assert.Bool(addr.IsIPv4()).IsTrue()
-	assert.Bytes(addr.IP).Equals(ip)
-	assert.Uint16(addr.Port).Equals(port)
+	assert.Bytes(addr.IP()).Equals(ip)
+	assert.Uint16(addr.Port()).Equals(port)
 	assert.String(addr.String()).Equals("1.2.3.4:80")
 }
 
@@ -32,10 +31,9 @@ func TestIPv6Address(t *testing.T) {
 	port := uint16(443)
 	addr := IPAddress(ip, port)
 
-	assert.Byte(addr.Type).Equals(AddrTypeIP)
 	assert.Bool(addr.IsIPv6()).IsTrue()
-	assert.Bytes(addr.IP).Equals(ip)
-	assert.Uint16(addr.Port).Equals(port)
+	assert.Bytes(addr.IP()).Equals(ip)
+	assert.Uint16(addr.Port()).Equals(port)
 	assert.String(addr.String()).Equals("[102:304:102:304:102:304:102:304]:443")
 }
 
@@ -46,9 +44,8 @@ func TestDomainAddress(t *testing.T) {
 	port := uint16(443)
 	addr := DomainAddress(domain, port)
 
-	assert.Byte(addr.Type).Equals(AddrTypeDomain)
 	assert.Bool(addr.IsDomain()).IsTrue()
-	assert.String(addr.Domain).Equals(domain)
-	assert.Uint16(addr.Port).Equals(port)
+	assert.String(addr.Domain()).Equals(domain)
+	assert.Uint16(addr.Port()).Equals(port)
 	assert.String(addr.String()).Equals("v2ray.com:443")
 }
diff --git a/proxy/vmess/protocol/vmess.go b/proxy/vmess/protocol/vmess.go
index 570c6b69..13012521 100644
--- a/proxy/vmess/protocol/vmess.go
+++ b/proxy/vmess/protocol/vmess.go
@@ -211,22 +211,19 @@ func (request *VMessRequest) ToBytes(idHash user.CounterHash, randomRangeInt64 u
 	buffer = append(buffer, request.RequestKey[:]...)
 	buffer = append(buffer, request.ResponseHeader[:]...)
 	buffer = append(buffer, request.Command)
-
-	portBytes := make([]byte, 2)
-	binary.BigEndian.PutUint16(portBytes, request.Address.Port)
-	buffer = append(buffer, portBytes...)
+	buffer = append(buffer, request.Address.PortBytes()...)
 
 	switch {
 	case request.Address.IsIPv4():
 		buffer = append(buffer, addrTypeIPv4)
-		buffer = append(buffer, request.Address.IP...)
+		buffer = append(buffer, request.Address.IP()...)
 	case request.Address.IsIPv6():
 		buffer = append(buffer, addrTypeIPv6)
-		buffer = append(buffer, request.Address.IP...)
+		buffer = append(buffer, request.Address.IP()...)
 	case request.Address.IsDomain():
 		buffer = append(buffer, addrTypeDomain)
-		buffer = append(buffer, byte(len(request.Address.Domain)))
-		buffer = append(buffer, []byte(request.Address.Domain)...)
+		buffer = append(buffer, byte(len(request.Address.Domain())))
+		buffer = append(buffer, []byte(request.Address.Domain())...)
 	}
 
 	paddingLength := mrand.Intn(32) + 1
diff --git a/proxy/vmess/vmessout.go b/proxy/vmess/vmessout.go
index 5ed8ad54..4248801e 100644
--- a/proxy/vmess/vmessout.go
+++ b/proxy/vmess/vmessout.go
@@ -72,7 +72,7 @@ func startCommunicate(request *protocol.VMessRequest, dest *v2net.Destination, r
 	input := ray.OutboundInput()
 	output := ray.OutboundOutput()
 
-	conn, err := net.DialTCP(dest.Network(), nil, &net.TCPAddr{dest.Address().IP, int(dest.Address().Port), ""})
+	conn, err := net.DialTCP(dest.Network(), nil, &net.TCPAddr{dest.Address().IP(), int(dest.Address().Port()), ""})
 	if err != nil {
 		log.Error("Failed to open tcp (%s): %v", dest.String(), err)
 		close(output)