diff --git a/go.mod b/go.mod
index 73255a0..15870e7 100644
--- a/go.mod
+++ b/go.mod
@@ -1,9 +1,10 @@
-module github.com/fd/go-nat
+module github.com/Inuart/go-nat
 
 require (
 	github.com/huin/goupnp v0.0.0-20180415215157-1395d1447324
 	github.com/jackpal/gateway v1.0.5
 	github.com/jackpal/go-nat-pmp v1.0.1
-	golang.org/x/net v0.0.0-20180524181706-dfa909b99c79
-	golang.org/x/text v0.3.0
+	github.com/koron/go-ssdp v0.0.0-20180514024734-4a0ed625a78b
+	golang.org/x/net v0.0.0-20180524181706-dfa909b99c79 // indirect
+	golang.org/x/text v0.3.0 // indirect
 )
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..c5e884f
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,12 @@
+github.com/huin/goupnp v0.0.0-20180415215157-1395d1447324 h1:PV190X5/DzQ/tbFFG5YpT5mH6q+cHlfgqI5JuRnH9oE=
+github.com/huin/goupnp v0.0.0-20180415215157-1395d1447324/go.mod h1:MZ2ZmwcBpvOoJ22IJsc7va19ZwoheaBk43rKg12SKag=
+github.com/jackpal/gateway v1.0.5 h1:qzXWUJfuMdlLMtt0a3Dgt+xkWQiA5itDEITVJtuSwMc=
+github.com/jackpal/gateway v1.0.5/go.mod h1:lTpwd4ACLXmpyiCTRtfiNyVnUmqT9RivzCDQetPfnjA=
+github.com/jackpal/go-nat-pmp v1.0.1 h1:i0LektDkO1QlrTm/cSuP+PyBCDnYvjPLGl4LdWEMiaA=
+github.com/jackpal/go-nat-pmp v1.0.1/go.mod h1:QPH045xvCAeXUZOxsnwmrtiCoxIr9eob+4orBN1SBKc=
+github.com/koron/go-ssdp v0.0.0-20180514024734-4a0ed625a78b h1:wxtKgYHEncAU00muMD06dzLiahtGM1eouRNOzVV7tdQ=
+github.com/koron/go-ssdp v0.0.0-20180514024734-4a0ed625a78b/go.mod h1:5Ky9EC2xfoUKUor0Hjgi2BJhCSXJfMOFlmyYrVKGQMk=
+golang.org/x/net v0.0.0-20180524181706-dfa909b99c79 h1:1FDlG4HI84rVePw1/0E/crL5tt2N+1blLJpY6UZ6krs=
+golang.org/x/net v0.0.0-20180524181706-dfa909b99c79/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/nat.go b/nat.go
index eb574d6..b20220d 100644
--- a/nat.go
+++ b/nat.go
@@ -32,6 +32,9 @@ type NAT interface {
 
 	// DeletePortMapping removes a port mapping.
 	DeletePortMapping(protocol string, internalPort int) (err error)
+
+	// DeleteExternalPortMapping removes an external port mapping.
+	DeleteExternalPortMapping(protocol string, externalPort int) (err error)
 }
 
 // DiscoverGateway attempts to find a gateway device.
diff --git a/natpmp.go b/natpmp.go
index 395a5dd..2fb1cea 100644
--- a/natpmp.go
+++ b/natpmp.go
@@ -5,7 +5,7 @@ import (
 	"time"
 
 	"github.com/jackpal/gateway"
-	"github.com/jackpal/go-nat-pmp"
+	natpmp "github.com/jackpal/go-nat-pmp"
 )
 
 var (
@@ -110,6 +110,10 @@ func (n *natpmpNAT) DeletePortMapping(protocol string, internalPort int) (err er
 	return nil
 }
 
+func (u *natpmpNAT) DeleteExternalPortMapping(protocol string, externalPort int) error {
+	return nil
+}
+
 func (n *natpmpNAT) Type() string {
 	return "NAT-PMP"
 }
diff --git a/upnp.go b/upnp.go
index caad350..7cd7624 100644
--- a/upnp.go
+++ b/upnp.go
@@ -257,6 +257,18 @@ func (u *upnp_NAT) DeletePortMapping(protocol string, internalPort int) error {
 	return nil
 }
 
+func (u *upnp_NAT) DeleteExternalPortMapping(protocol string, externalPort int) error {
+	if externalPort <= 0 {
+		return nil
+	}
+	for i, e := range u.ports {
+		if e == externalPort {
+			delete(u.ports, i)
+		}
+	}
+	return u.c.DeletePortMapping("", uint16(externalPort), mapProtocol(protocol))
+}
+
 func (u *upnp_NAT) GetDeviceAddress() (net.IP, error) {
 	addr, err := net.ResolveUDPAddr("udp4", u.rootDevice.URLBase.Host)
 	if err != nil {