diff --git a/main.cpp b/main.cpp
index 0235d84..522cf68 100644
--- a/main.cpp
+++ b/main.cpp
@@ -10,6 +10,8 @@
 #include "ppapi/cpp/input_event.h"
 
 #include <netinet/in.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
 
 // Requests the NaCl module to connection to the server specified after the :
 #define MSG_START_REQUEST "startRequest"
@@ -162,6 +164,8 @@ void MoonlightInstance::HandleMessage(const pp::Var& var_message) {
         MakeCert(callbackId, params);
     } else if (strcmp(method.c_str(), "pair") == 0) {
         HandlePair(callbackId, params);
+    } else if (strcmp(method.c_str(), "STUN") == 0) {
+        HandleSTUN(callbackId, params);
     } else {
         pp::Var response("Unhandled message received: " + method);
         PostMessage(response);
@@ -277,6 +281,29 @@ void MoonlightInstance::PairCallback(int32_t /*result*/, int32_t callbackId, pp:
     PostMessage(ret);
 }
 
+void MoonlightInstance::HandleSTUN(int32_t callbackId, pp::VarArray args) {
+     m_HttpThreadPool[m_HttpThreadPoolSequence++ % HTTP_HANDLER_THREADS]->message_loop().PostWork(
+         m_CallbackFactory.NewCallback(&MoonlightInstance::STUNCallback, callbackId, args));
+}
+
+void MoonlightInstance::STUNCallback(int32_t /*result*/, int32_t callbackId, pp::VarArray args) {
+    unsigned int wanAddr;
+    char addrStr[128] = {};
+    
+    pp::VarDictionary ret;
+    ret.Set("callbackId", pp::Var(callbackId));
+    ret.Set("type", pp::Var("resolve"));
+
+    if (LiFindExternalAddressIP4("stun.stunprotocol.org", 3478, &wanAddr) == 0) {
+        inet_ntop(AF_INET, &wanAddr, addrStr, sizeof(addrStr));
+        ret.Set("ret", pp::Var(addrStr));
+    } else {
+        ret.Set("ret", pp::Var());
+    }
+
+    PostMessage(ret);
+}
+
 bool MoonlightInstance::Init(uint32_t argc,
                              const char* argn[],
                              const char* argv[]) {
diff --git a/moonlight.hpp b/moonlight.hpp
index 4f43413..7b311bc 100644
--- a/moonlight.hpp
+++ b/moonlight.hpp
@@ -97,7 +97,9 @@ class MoonlightInstance : public pp::Instance, public pp::MouseLock {
         void HandleStartStream(int32_t callbackId, pp::VarArray args);
         void HandleStopStream(int32_t callbackId, pp::VarArray args);
         void HandleOpenURL(int32_t callbackId, pp::VarArray args);
+        void HandleSTUN(int32_t callbackId, pp::VarArray args);
         void PairCallback(int32_t /*result*/, int32_t callbackId, pp::VarArray args);
+        void STUNCallback(int32_t /*result*/, int32_t callbackId, pp::VarArray args);
     
         bool HandleInputEvent(const pp::InputEvent& event);
         void ReportMouseMovement();
diff --git a/static/js/index.js b/static/js/index.js
index 6d6c649..43a8c45 100644
--- a/static/js/index.js
+++ b/static/js/index.js
@@ -107,6 +107,7 @@ function restoreUiAfterNaClLoad() {
             if (hosts[returneMdnsDiscoveredHost.serverUid] != null) {
               // if we're seeing a host we've already seen before, update it for the current local IP.
               hosts[returneMdnsDiscoveredHost.serverUid].address = returneMdnsDiscoveredHost.address;
+              hosts[returneMdnsDiscoveredHost.serverUid].updateExternalAddressIP4();
             } else {
               // Host must be in the grid before starting background polling
               addHostToGrid(returneMdnsDiscoveredHost, true);
@@ -405,6 +406,9 @@ function addHostToGrid(host, ismDNSDiscovered) {
   }
   $('#host-grid').append(outerDiv);
   hosts[host.serverUid] = host;
+  if (ismDNSDiscovered) {
+    hosts[host.serverUid].updateExternalAddressIP4();
+  }
 }
 
 function removeClicked(host) {
diff --git a/static/js/utils.js b/static/js/utils.js
index 9a0ef2a..ee73f51 100644
--- a/static/js/utils.js
+++ b/static/js/utils.js
@@ -244,7 +244,14 @@ NvHTTP.prototype = {
     this.serverMajorVersion = parseInt(this.appVersion.substring(0, 1), 10);
     this.serverUid = $root.find('uniqueid').text().trim();
     this.hostname = $root.find('hostname').text().trim();
-    this.externalIP = $root.find('ExternalIP').text().trim();
+
+    var externIP = $root.find('ExternalIP').text().trim();
+    if (externIP) {
+      // New versions of GFE don't have this field, so don't overwrite
+      // the one we found via STUN
+      this.externalIP = externIP;
+    }
+
     try { //  these aren't critical for functionality, and don't necessarily exist in older GFE versions.
       this.GfeVersion = $root.find('GfeVersion').text().trim();
       this.gputype = $root.find('gputype').text().trim();
@@ -439,6 +446,18 @@ NvHTTP.prototype = {
       .then(this.refreshServerInfo());
   },
 
+  updateExternalAddressIP4: function() {
+    console.log('%c[utils.js, updateExternalAddressIP4]', 'color: gray;', 'Finding external IPv4 address for ' + this.hostname);
+    return sendMessage('STUN').then(function(addr) {
+      if (addr) {
+        this.externalIP = addr
+        console.log('%c[utils.js, updateExternalAddressIP4]', 'color: gray;', 'Found external IPv4 address: ' + this.hostname + ' -> ' + this.externalIP);
+      } else {
+        console.log('%c[utils.js, updateExternalAddressIP4]', 'color: gray;', 'External IPv4 address lookup failed');
+      }
+    }.bind(this))
+  },
+
   pair: function(randomNumber) {
     return this.refreshServerInfo().then(function() {
       if (this.paired)