diff --git a/src/mavesp8266.cpp b/src/mavesp8266.cpp
index baa20134..7e0e3956 100644
--- a/src/mavesp8266.cpp
+++ b/src/mavesp8266.cpp
@@ -201,3 +201,24 @@ void MavESP8266Bridge::handle_non_mavlink(uint8_t b, bool msgReceived)
     }
     _last_parse_state = _rxstatus.parse_state;
 }
+
+/*
+    helper to check if a message is restricted to pass through the bridge
+*/
+bool MavESP8266Bridge::restricted_message(mavlink_message_t* message)
+{
+    if (getWorld()->getParameters()->getWifiCastMode() != CAST_MODE_CONS_MULTI) {
+        // restrict messages only in conservative multicast mode
+        return false;
+    }
+
+    // allowed messages
+    switch(message->msgid) {
+    case MAVLINK_MSG_ID_GLOBAL_POSITION_INT:
+    case MAVLINK_MSG_ID_FOLLOW_TARGET:
+        return false;
+    }
+
+    // restrict all other messages
+    return true;
+}
diff --git a/src/mavesp8266.h b/src/mavesp8266.h
index 4611e8d6..0a4d9d17 100644
--- a/src/mavesp8266.h
+++ b/src/mavesp8266.h
@@ -121,6 +121,7 @@ class MavESP8266Bridge {
     mavlink_status_t        _rxstatus;
 
     void handle_non_mavlink(uint8_t b, bool msgReceived);
+    bool restricted_message(mavlink_message_t* message);
     uint8_t _non_mavlink_buffer[270];
     uint16_t _non_mavlink_len;
     mavlink_parse_state_t _last_parse_state;
diff --git a/src/mavesp8266_gcs.cpp b/src/mavesp8266_gcs.cpp
index 4f23d190..88e39e55 100644
--- a/src/mavesp8266_gcs.cpp
+++ b/src/mavesp8266_gcs.cpp
@@ -55,11 +55,21 @@ void
 MavESP8266GCS::begin(MavESP8266Bridge* forwardTo, IPAddress gcsIP)
 {
     MavESP8266Bridge::begin(forwardTo);
-    _ip = gcsIP;
+
     //-- Init variables that shouldn't change unless we reboot
-    _udp_port = getWorld()->getParameters()->getWifiUdpHport();
     //-- Start UDP
-    _udp.begin(getWorld()->getParameters()->getWifiUdpCport());
+    switch(getWorld()->getParameters()->getWifiCastMode()) {
+    case CAST_MODE_UNI:
+        _ip = gcsIP;
+        _udp_port = getWorld()->getParameters()->getWifiUdpHport();
+        _udp.begin(getWorld()->getParameters()->getWifiUdpCport());
+        break;
+    case CAST_MODE_FULL_MULTI ... CAST_MODE_CONS_MULTI:
+        _ip = getWorld()->getParameters()->getWifiMcastIP();
+        _udp_port = getWorld()->getParameters()->getWifiMcastPort();
+        _udp.beginMulticast(WiFi.localIP(), _ip, _udp_port);
+        break;
+    }
 }
 
 //---------------------------------------------------------------------------------
@@ -70,7 +80,9 @@ MavESP8266GCS::readMessage()
     //-- Read UDP
     if(_readMessage()) {
         //-- If we have a message, forward it
-        _forwardTo->sendMessage(&_message);
+        if(!restricted_message(&_message)) {
+            _forwardTo->sendMessage(&_message);
+        }
         memset(&_message, 0, sizeof(_message));
     }
     uint32_t now = millis();
@@ -120,48 +132,50 @@ MavESP8266GCS::_readMessage()
                 if(msgReceived) {
                     //-- We no longer need to broadcast
                     _status.packets_received++;
-                    if(_ip[3] == 255) {
-                        _ip = _udp.remoteIP();
-                        getWorld()->getLogger()->log("Response from GCS. Setting GCS IP to: %s\n", _ip.toString().c_str());
-                    }
-                    //-- First packets
-                    if(!_heard_from) {
-                        if(_message.msgid == MAVLINK_MSG_ID_HEARTBEAT) {
-                            //-- We no longer need DHCP
-                            if(getWorld()->getParameters()->getWifiMode() == WIFI_MODE_AP) {
-                                wifi_softap_dhcps_stop();
+                    if(getWorld()->getParameters()->getWifiCastMode() == CAST_MODE_UNI) {
+                        if (_ip[3] == 255) {
+                            _ip = _udp.remoteIP();
+                            getWorld()->getLogger()->log("Response from GCS. Setting GCS IP to: %s\n", _ip.toString().c_str());
+                        }
+                        //-- First packets
+                        if(!_heard_from) {
+                            if(_message.msgid == MAVLINK_MSG_ID_HEARTBEAT) {
+                                //-- We no longer need DHCP
+                                if(getWorld()->getParameters()->getWifiMode() == WIFI_MODE_AP) {
+                                    wifi_softap_dhcps_stop();
+                                }
+                                _heard_from      = true;
+                                _system_id       = _message.sysid;
+                                _component_id    = _message.compid;
+                                _seq_expected    = _message.seq + 1;
+                                _last_heartbeat  = millis();
                             }
-                            _heard_from      = true;
-                            _system_id       = _message.sysid;
-                            _component_id    = _message.compid;
-                            _seq_expected    = _message.seq + 1;
-                            _last_heartbeat  = millis();
+                        } else {
+                            if(_message.msgid == MAVLINK_MSG_ID_HEARTBEAT)
+                                _last_heartbeat = millis();
+                            _checkLinkErrors(&_message);
                         }
-                    } else {
-                        if(_message.msgid == MAVLINK_MSG_ID_HEARTBEAT)
-                            _last_heartbeat = millis();
-                        _checkLinkErrors(&_message);
-                    }
 
-                    if (msgReceived == MAVLINK_FRAMING_BAD_CRC) {
-                        // we don't process messages locally with bad CRC,
-                        // but we do forward them, so when new messages
-                        // are added we can bridge them
-                        break;
-                    }
+                        if (msgReceived == MAVLINK_FRAMING_BAD_CRC) {
+                            // we don't process messages locally with bad CRC,
+                            // but we do forward them, so when new messages
+                            // are added we can bridge them
+                            break;
+                        }
 
 #ifdef MAVLINK_FRAMING_BAD_SIGNATURE
-                    if (msgReceived == MAVLINK_FRAMING_BAD_SIGNATURE) {
-                        break;
-                    }
+                        if (msgReceived == MAVLINK_FRAMING_BAD_SIGNATURE) {
+                            break;
+                        }
 #endif
-                    
-                    //-- Check for message we might be interested
-                    if(getWorld()->getComponent()->handleMessage(this, &_message)){
-                        //-- Eat message (don't send it to FC)
-                        memset(&_message, 0, sizeof(_message));
-                        msgReceived = false;
-                        continue;
+                        
+                        //-- Check for message we might be interested
+                        if(getWorld()->getComponent()->handleMessage(this, &_message)){
+                            //-- Eat message (don't send it to FC)
+                            memset(&_message, 0, sizeof(_message));
+                            msgReceived = false;
+                            continue;
+                        }
                     }
 
 
@@ -171,7 +185,7 @@ MavESP8266GCS::_readMessage()
             }
         }
     }
-    if(!msgReceived) {
+    if(!msgReceived && getWorld()->getParameters()->getWifiCastMode() == CAST_MODE_UNI) {
         if(_heard_from && (millis() - _last_heartbeat) > HEARTBEAT_TIMEOUT) {
             //-- Restart DHCP and start broadcasting again
             if(getWorld()->getParameters()->getWifiMode() == WIFI_MODE_AP) {
@@ -223,6 +237,15 @@ MavESP8266GCS::sendMessage(mavlink_message_t* message) {
 int
 MavESP8266GCS::sendMessageRaw(uint8_t *buffer, int len)
 {
+    switch(getWorld()->getParameters()->getWifiCastMode()) {
+    case CAST_MODE_UNI:
+        _udp.beginPacket(_ip, _udp_port);
+        break;
+        
+    case CAST_MODE_FULL_MULTI ... CAST_MODE_CONS_MULTI:
+        _udp.beginPacketMulticast(_ip, _udp_port, WiFi.localIP());
+        break;
+    }
     _udp.beginPacket(_ip, _udp_port);
     size_t sent = _udp.write(buffer, len);
     _udp.endPacket();
diff --git a/src/mavesp8266_httpd.cpp b/src/mavesp8266_httpd.cpp
index 3ea8dad5..6f1d325e 100644
--- a/src/mavesp8266_httpd.cpp
+++ b/src/mavesp8266_httpd.cpp
@@ -66,6 +66,9 @@ const char* kDEBUG      = "debug";
 const char* kREBOOT     = "reboot";
 const char* kPOSITION   = "position";
 const char* kMODE       = "mode";
+const char* kCASTMODE   = "castmode";
+const char* kMCASTIP    = "mcastip";
+const char* kMCASTPORT  = "mcastport";
 
 const char* kFlashMaps[7] = {
     "512KB (256/256)",
@@ -325,6 +328,34 @@ static void handle_setup()
     message += "<input type='text' name='cport' value='";
     message += getWorld()->getParameters()->getWifiUdpCport();
     message += "'><br>";
+
+    message += "Casting Mode:&nbsp;";
+    message += "<input type='radio' name='castmode' value='0'";
+    if (getWorld()->getParameters()->getWifiCastMode() == CAST_MODE_UNI) {
+        message += " checked";
+    }
+    message += ">Unicast\n";
+    message += "<input type='radio' name='castmode' value='1'";
+    if (getWorld()->getParameters()->getWifiCastMode() == CAST_MODE_FULL_MULTI) {
+        message += " checked";
+    }
+    message += ">Full Multicast\n";
+    message += "<input type='radio' name='castmode' value='2'";
+    if (getWorld()->getParameters()->getWifiCastMode() == CAST_MODE_CONS_MULTI) {
+        message += " checked";
+    }
+    message += ">Conservative Multicast<br>\n";
+
+    message += "Multicast IP:&nbsp;";
+    message += "<input type='text' name='mcastip' value='";
+    IP = getWorld()->getParameters()->getWifiMcastIP();
+    message += IP.toString();
+    message += "'><br>";
+
+    message += "Multicast Port:&nbsp;";
+    message += "<input type='text' name='mcastport' value='";
+    message += getWorld()->getParameters()->getWifiMcastPort();
+    message += "'><br>";
     
     message += "Baudrate:&nbsp;";
     message += "<input type='text' name='baud' value='";
@@ -537,6 +568,19 @@ void handle_setParameters()
         ok = true;
         reboot = webServer.arg(kREBOOT) == "1";
     }
+    if(webServer.hasArg(kCASTMODE)) {
+        ok = true;
+        getWorld()->getParameters()->setWifiCastMode(webServer.arg(kCASTMODE).toInt());
+    }
+    if(webServer.hasArg(kMCASTIP)) {
+        IPAddress ip;
+        ip.fromString(webServer.arg(kMCASTIP).c_str());
+        getWorld()->getParameters()->setWifiMcastIP(ip);
+    }
+    if(webServer.hasArg(kMCASTPORT)) {
+        ok = true;
+        getWorld()->getParameters()->setWifiMcastPort(webServer.arg(kMCASTPORT).toInt());
+    }
     if(ok) {
         getWorld()->getParameters()->saveAllToEeprom();
         //-- Send new parameters back
diff --git a/src/mavesp8266_parameters.cpp b/src/mavesp8266_parameters.cpp
index 78df1232..ca827ddd 100644
--- a/src/mavesp8266_parameters.cpp
+++ b/src/mavesp8266_parameters.cpp
@@ -65,6 +65,9 @@ uint32_t    _wifi_subnetsta;
 uint32_t    _uart_baud_rate;
 uint32_t    _flash_left;
 int8_t      _raw_enable;
+int8_t      _wifi_cast_mode;
+uint32_t    _wifi_mcast_ip;
+uint16_t    _wifi_mcast_port;
 
 //-- Parameters
 //   No string support in parameters so we stash a char[16] into 4 uint32_t
@@ -97,6 +100,9 @@ int8_t      _raw_enable;
      {"WIFI_SUBNET_STA",    &_wifi_subnetsta,       MavESP8266Parameters::ID_SUBNETSTA, sizeof(uint32_t),   MAV_PARAM_TYPE_UINT32,  false},
      {"UART_BAUDRATE",      &_uart_baud_rate,       MavESP8266Parameters::ID_UART,      sizeof(uint32_t),   MAV_PARAM_TYPE_UINT32,  false},
      {"RAW_ENABLE",         &_raw_enable,           MavESP8266Parameters::ID_RAW_ENABLE,sizeof(int8_t),     MAV_PARAM_TYPE_INT8,    false},
+     {"WIFI_CAST_MODE",     &_wifi_cast_mode,       MavESP8266Parameters::ID_CAST_MODE, sizeof(int8_t),     MAV_PARAM_TYPE_INT8,    false},
+     {"WIFI_MCAST_IP",      &_wifi_mcast_ip,        MavESP8266Parameters::ID_MCAST_IP,  sizeof(uint32_t),   MAV_PARAM_TYPE_UINT32,  false},
+     {"WIFI_MCAST_PORT",    &_wifi_mcast_port,      MavESP8266Parameters::ID_MCAST_PORT,sizeof(uint16_t),   MAV_PARAM_TYPE_UINT16,  false},
 };
 
 //---------------------------------------------------------------------------------
@@ -154,6 +160,9 @@ uint32_t    MavESP8266Parameters::getWifiStaGateway () { return _wifi_gatewaysta
 uint32_t    MavESP8266Parameters::getWifiStaSubnet  () { return _wifi_subnetsta;    }
 uint32_t    MavESP8266Parameters::getUartBaudRate   () { return _uart_baud_rate;    }
 int8_t      MavESP8266Parameters::getRawEnable      () { return _raw_enable;        }
+int8_t      MavESP8266Parameters::getWifiCastMode   () { return _wifi_cast_mode;    }
+uint32_t    MavESP8266Parameters::getWifiMcastIP    () { return _wifi_mcast_ip;     }
+uint16_t    MavESP8266Parameters::getWifiMcastPort  () { return _wifi_mcast_port;   }
 
 //---------------------------------------------------------------------------------
 //-- Reset all to defaults
@@ -170,6 +179,9 @@ MavESP8266Parameters::resetToDefaults()
     _wifi_ipsta        = 0;
     _wifi_gatewaysta   = 0;
     _wifi_subnetsta    = 0;
+    _wifi_cast_mode    = 0;
+    _wifi_mcast_ip     = DEFAULT_MCAST_IP;
+    _wifi_mcast_port   = DEFAULT_UDP_HPORT;
     strncpy(_wifi_ssid,         kDEFAULT_SSID,      sizeof(_wifi_ssid));
     strncpy(_wifi_password,     kDEFAULT_PASSWORD,  sizeof(_wifi_password));
     strncpy(_wifi_ssidsta,      kDEFAULT_SSID,      sizeof(_wifi_ssidsta));
@@ -412,3 +424,24 @@ MavESP8266Parameters::setUartBaudRate(uint32_t baud)
 {
     _uart_baud_rate = baud;
 }
+
+//---------------------------------------------------------------------------------
+void
+MavESP8266Parameters::setWifiCastMode(int8_t enabled)
+{
+    _wifi_cast_mode = enabled;
+}
+
+//---------------------------------------------------------------------------------
+void
+MavESP8266Parameters::setWifiMcastIP(uint32_t ip)
+{
+    _wifi_mcast_ip = ip;
+}
+
+//---------------------------------------------------------------------------------
+void
+MavESP8266Parameters::setWifiMcastPort(uint16_t port)
+{
+    _wifi_mcast_port = port;
+}
diff --git a/src/mavesp8266_parameters.h b/src/mavesp8266_parameters.h
index e45559e1..3323b258 100644
--- a/src/mavesp8266_parameters.h
+++ b/src/mavesp8266_parameters.h
@@ -41,12 +41,17 @@
 #define WIFI_MODE_AP 0
 #define WIFI_MODE_STA 1
 
+#define CAST_MODE_UNI 0
+#define CAST_MODE_FULL_MULTI 1
+#define CAST_MODE_CONS_MULTI 2
+
 //-- Constants
 #define DEFAULT_WIFI_MODE       WIFI_MODE_AP
 #define DEFAULT_UART_SPEED      921600
 #define DEFAULT_WIFI_CHANNEL    11
 #define DEFAULT_UDP_HPORT       14550
 #define DEFAULT_UDP_CPORT       14555
+#define DEFAULT_MCAST_IP        848429039
 
 struct stMavEspParameters {
     char        id[MAVLINK_MSG_PARAM_VALUE_FIELD_PARAM_ID_LEN];
@@ -90,7 +95,10 @@ class MavESP8266Parameters {
         ID_SUBNETSTA,
         ID_UART,
         ID_RAW_ENABLE,
-        ID_COUNT
+        ID_CAST_MODE,
+        ID_MCAST_IP,
+        ID_MCAST_PORT,
+        ID_COUNT,
     };
 
     void        begin                       ();
@@ -114,6 +122,9 @@ class MavESP8266Parameters {
     uint32_t    getWifiStaSubnet            ();
     uint32_t    getUartBaudRate             ();
     int8_t      getRawEnable                ();
+    int8_t      getWifiCastMode             ();
+    uint32_t    getWifiMcastIP              ();
+    uint16_t    getWifiMcastPort            ();
 
     void        setDebugEnabled             (int8_t enabled);
     void        setWifiMode                 (int8_t mode);
@@ -129,6 +140,9 @@ class MavESP8266Parameters {
     void        setWifiStaSubnet            (uint32_t addr);
     void        setUartBaudRate             (uint32_t baud);
     void        setLocalIPAddress           (uint32_t ipAddress);
+    void        setWifiCastMode             (int8_t mode);
+    void        setWifiMcastIP              (uint32_t ip);
+    void        setWifiMcastPort            (uint16_t port);
 
     stMavEspParameters* getAt               (int index);
 
diff --git a/src/mavesp8266_vehicle.cpp b/src/mavesp8266_vehicle.cpp
index e3f2337f..e41d9b02 100644
--- a/src/mavesp8266_vehicle.cpp
+++ b/src/mavesp8266_vehicle.cpp
@@ -72,7 +72,9 @@ void
 MavESP8266Vehicle::readMessage()
 {
     if (_readMessage()) {
-        _forwardTo->sendMessage(&_msg);
+        if(!restricted_message(&_msg)) {
+            _forwardTo->sendMessage(&_msg);
+        }
     }
     //-- Update radio status (1Hz)
     if(_heard_from && (millis() - _last_status_time > 1000)) {