diff --git a/server/CommandListener.cpp b/server/CommandListener.cpp
index b57ec75..ededddb 100644
--- a/server/CommandListener.cpp
+++ b/server/CommandListener.cpp
@@ -587,6 +587,7 @@
                                                       int argc, char **argv) {
     int rc = 0;
 
+    ALOGD("TetherCmd::runCommand. argc: %d. argv[0]: %s", argc, argv[0]);
     if (argc < 2) {
         cli->sendMsg(ResponseCode::CommandSyntaxError, "Missing argument", false);
         return 0;
@@ -655,6 +656,11 @@
             } else if (!strcmp(argv[2], "remove")) {
                 rc = sTetherCtrl->untetherInterface(argv[3]);
             /* else if (!strcmp(argv[2], "list")) handled above */
+            } else if (!strcmp(argv[2], "add_upstream")) {
+                ALOGD("command %s %s %s %s", argv[0], argv[1], argv[2], argv[3]);
+                rc = sTetherCtrl->addUpstreamInterface(argv[3]);
+            } else if (!strcmp(argv[2], "remove_upstream")) {
+                rc = sTetherCtrl->removeUpstreamInterface(argv[3]);
             } else {
                 cli->sendMsg(ResponseCode::CommandParameterError,
                              "Unknown tether interface operation", false);
@@ -689,6 +695,74 @@
     return 0;
 }
 
+CommandListener::V6RtrAdvCmd::V6RtrAdvCmd() :
+                 NetdCommand("v6rtradv") {
+}
+
+int CommandListener::V6RtrAdvCmd::runCommand(SocketClient *cli,
+                                                      int argc, char **argv) {
+    int rc = 0;
+
+    if (argc < 2) {
+        cli->sendMsg(ResponseCode::CommandSyntaxError, "Missing argument", false);
+        return 0;
+    }
+
+    if (!strcmp(argv[1], "stop")) {
+        rc = sTetherCtrl->stopV6RtrAdv();
+    } else if (!strcmp(argv[1], "status")) {
+        char *tmp = NULL;
+
+        asprintf(&tmp, "IPv6 Router Advertisement service %s",
+                 (sTetherCtrl->isV6RtrAdvStarted() ? "started" : "stopped"));
+        cli->sendMsg(ResponseCode::V6RtrAdvResult, tmp, false);
+        free(tmp);
+        return 0;
+    } else {
+        /*
+         * These commands take a minimum of 4 arguments
+         */
+        if (argc < 4) {
+            cli->sendMsg(ResponseCode::CommandSyntaxError, "Missing argument", false);
+            return 0;
+        }
+
+        if (!strcmp(argv[1], "start")) {
+            int num_ifaces = argc - 2;
+            int arg_index = 2;
+            rc = sTetherCtrl->startV6RtrAdv(num_ifaces, &argv[arg_index]);
+        } else if (!strcmp(argv[1], "interface")) {
+            if (!strcmp(argv[2], "add")) {
+                rc = sTetherCtrl->tetherInterface(argv[3]);
+            } else if (!strcmp(argv[2], "remove")) {
+                rc = sTetherCtrl->untetherInterface(argv[3]);
+            } else if (!strcmp(argv[2], "list")) {
+                InterfaceCollection *ilist = sTetherCtrl->getTetheredInterfaceList();
+                InterfaceCollection::iterator it;
+
+                for (it = ilist->begin(); it != ilist->end(); ++it) {
+                    cli->sendMsg(ResponseCode::TetherInterfaceListResult, *it, false);
+                }
+            } else {
+                cli->sendMsg(ResponseCode::CommandParameterError,
+                             "Unknown tether interface operation", false);
+                return 0;
+            }
+        } else {
+            cli->sendMsg(ResponseCode::CommandSyntaxError, "Unknown v6rtradv cmd", false);
+            return 0;
+        }
+    }
+
+    if (!rc) {
+        cli->sendMsg(ResponseCode::CommandOkay, "V6RtrAdv operation succeeded", false);
+    } else {
+        cli->sendMsg(ResponseCode::OperationFailed, "V6RtrAdv operation failed", true);
+    }
+
+    return 0;
+}
+
 CommandListener::NatCmd::NatCmd() :
                  NetdCommand("nat") {
 }
diff --git a/server/CommandListener.h b/server/CommandListener.h
index 7819db6..c1f7867 100644
--- a/server/CommandListener.h
+++ b/server/CommandListener.h
@@ -94,6 +94,13 @@
         int runCommand(SocketClient *c, int argc, char ** argv);
     };
 
+    class V6RtrAdvCmd: public NetdCommand {
+    public:
+        V6RtrAdvCmd();
+        virtual ~V6RtrAdvCmd() {}
+        int runCommand(SocketClient *c, int argc, char ** argv);
+    };
+
     class NatCmd : public NetdCommand {
     public:
         NatCmd();
diff --git a/server/ResponseCode.h b/server/ResponseCode.h
index 6a0c22c..594d997 100644
--- a/server/ResponseCode.h
+++ b/server/ResponseCode.h
@@ -46,6 +46,7 @@
     static const int TetheringStatsResult      = 221;
     static const int DnsProxyQueryResult       = 222;
     static const int ClatdStatusResult         = 223;
+    static const int V6RtrAdvResult            = 227;
 
     // 400 series - The command was accepted but the requested action
     // did not take place.
diff --git a/server/TetherController.cpp b/server/TetherController.cpp
index fb51c06..f710876 100644
--- a/server/TetherController.cpp
+++ b/server/TetherController.cpp
@@ -23,11 +23,15 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <linux/capability.h>
 
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
 #define LOG_TAG "TetherController"
+#define LOG_NDEBUG 0
+#define LOG_NDDEBUG 0
+#define LOG_NIDEBUG 0
 #include <cutils/log.h>
 #include <cutils/properties.h>
 
@@ -36,9 +40,20 @@
 #include "Permission.h"
 #include "TetherController.h"
 
+#include <private/android_filesystem_config.h>
+#include <unistd.h>
+
+#define RTRADVDAEMON "/system/bin/radish"
+#define IP4_CFG_IP_FORWARD          "/proc/sys/net/ipv4/ip_forward"
+#define IP6_CFG_ALL_PROXY_NDP       "/proc/sys/net/ipv6/conf/all/proxy_ndp"
+#define IP6_CFG_ALL_FORWARDING      "/proc/sys/net/ipv6/conf/all/forwarding"
+#define IP6_IFACE_CFG_ACCEPT_RA     "/proc/sys/net/ipv6/conf/%s/accept_ra"
+#define PROC_PATH_SIZE              255
+
+
 TetherController::TetherController() {
     mInterfaces = new InterfaceCollection();
-    mDnsNetId = 0;
+    mUpstreamInterfaces = new InterfaceCollection();
     mDnsForwarders = new NetAddressCollection();
     mDaemonFd = -1;
     mDaemonPid = 0;
@@ -52,9 +67,32 @@
     }
     mInterfaces->clear();
 
+    for (it = mUpstreamInterfaces->begin(); it != mUpstreamInterfaces->end(); ++it) {
+        free(*it);
+    }
+    mUpstreamInterfaces->clear();
+
     mDnsForwarders->clear();
 }
 
+static int config_write_setting(const char *path, const char *value)
+{
+    int fd = open(path, O_WRONLY);
+
+    ALOGD("config_write_setting(%s, %s)", path, value);
+    if (fd < 0) {
+        ALOGE("Failed to open %s (%s)", path, strerror(errno));
+        return -1;
+    }
+    if (write(fd, value, strlen(value)) != (int)strlen(value)) {
+        ALOGE("Failed to write to %s (%s)", path, strerror(errno));
+        close(fd);
+        return -1;
+    }
+    close(fd);
+    return 0;
+}
+
 int TetherController::setIpFwdEnabled(bool enable) {
 
     ALOGD("Setting IP forward enable = %d", enable);
@@ -78,6 +116,17 @@
         return -1;
     }
     close(fd);
+    if (config_write_setting(
+            IP6_CFG_ALL_PROXY_NDP, enable ? "2" : "0")) {
+        ALOGE("Failed to write proxy_ndp (%s)", strerror(errno));
+        return -1;
+    }
+    if (config_write_setting(
+            IP6_CFG_ALL_FORWARDING, enable ? "2" : "0")) {
+        ALOGE("Failed to write ip6 forwarding (%s)", strerror(errno));
+        return -1;
+    }
+
     return 0;
 }
 
@@ -198,6 +247,107 @@
     return (mDaemonPid == 0 ? false : true);
 }
 
+int TetherController::startV6RtrAdv(int num_ifaces, char **ifaces) {
+    int pid;
+    int num_processed_args = 1;
+    gid_t groups [] = { AID_NET_ADMIN, AID_NET_RAW, AID_INET };
+
+    if (num_ifaces < 2) {
+        ALOGD("Need atleast two interfaces to start Router advertisement daemon");
+        return 0;
+    }
+
+    if ((pid = fork()) < 0) {
+        ALOGE("%s: fork failed (%s)", __func__, strerror(errno));
+        return -1;
+    }
+    if (!pid) {
+        char **args;
+        const char *cmd = RTRADVDAEMON;
+
+        args = (char **)calloc(num_ifaces * 3 + 2, sizeof(char *));
+
+        args[0] = strdup(RTRADVDAEMON);
+        for (int i=0; i < num_ifaces; i++) {
+            int aidx = 3 * i + num_processed_args;
+            args[aidx] = (char *)"-i";
+            args[aidx + 1] = ifaces[i];
+            args[aidx + 2] = (char *)"-x";
+        }
+
+
+        setgroups(sizeof(groups)/sizeof(groups[0]), groups);
+        setresgid(AID_RADIO, AID_RADIO, AID_RADIO);
+        setresuid(AID_RADIO, AID_RADIO, AID_RADIO);
+
+        if (execv(cmd, args)) {
+            ALOGE("Unable to exec %s: (%s)" , cmd, strerror(errno));
+        }
+        free(args[0]);
+        free(args);
+        exit(0);
+    } else {
+        mRtrAdvPid = pid;
+        ALOGD("Router advertisement daemon running");
+    }
+    return 0;
+}
+
+int TetherController::stopV6RtrAdv() {
+    if (!mRtrAdvPid) {
+        ALOGD("Router advertisement daemon already stopped");
+        return 0;
+    }
+
+    kill(mRtrAdvPid, SIGTERM);
+    waitpid(mRtrAdvPid, NULL, 0);
+    mRtrAdvPid = 0;
+    ALOGD("Router advertisement daemon stopped");
+    return 0;
+}
+
+int TetherController::addV6RtrAdvIface(const char *iface) {
+    char **args;
+    int i;
+    int len;
+    InterfaceCollection::iterator it;
+    /* For now, just stop and start the daemon with the new interface list */
+
+    len = mInterfaces->size() + mUpstreamInterfaces->size();
+    ALOGD("addV6RtrAdvIface: len = %d. Iface: %s\n", len, iface);
+    args = (char **)calloc(len, sizeof(char *));
+
+    if (!args) {
+        errno = ENOMEM;
+        return -1;
+    }
+
+    for (i = 0, it = mInterfaces->begin(); it != mInterfaces->end(); it++, i++) {
+        args[i] = *it;
+    }
+
+    for (it = mUpstreamInterfaces->begin(); i < len && it != mUpstreamInterfaces->end(); it++, i++) {
+        args[i] = *it;
+    }
+
+    stopV6RtrAdv();
+    startV6RtrAdv(i, args);
+
+    free(args);
+
+    return 0;
+}
+
+int TetherController::removeV6RtrAdvIface(const char *iface) {
+    /* For now, just call addV6RtrAdvIface, since that will stop and
+     * start the daemon with the updated interfaces
+     */
+    return addV6RtrAdvIface(iface);
+}
+bool TetherController::isV6RtrAdvStarted() {
+    return (mRtrAdvPid == 0 ? false : true);
+}
+
 #define MAX_CMD_SIZE 1024
 
 int TetherController::setDnsForwarders(unsigned netId, char **servers, int numServers) {
@@ -252,6 +402,48 @@
     return mDnsNetId;
 }
 
+int TetherController::addUpstreamInterface(char *iface)
+{
+    InterfaceCollection::iterator it;
+
+    ALOGD("addUpstreamInterface(%s)\n", iface);
+
+    if (!iface) {
+        ALOGE("addUpstreamInterface: received null interface");
+        return 0;
+    }
+    for (it = mUpstreamInterfaces->begin(); it != mUpstreamInterfaces->end(); ++it) {
+        ALOGD(".");
+        if (*it && !strcmp(iface, *it)) {
+            ALOGD("addUpstreamInterface: interface %s already present", iface);
+            return 0;
+        }
+    }
+    mUpstreamInterfaces->push_back(strdup(iface));
+
+    return addV6RtrAdvIface(iface);
+}
+
+int TetherController::removeUpstreamInterface(char *iface)
+{
+    InterfaceCollection::iterator it;
+
+    if (!iface) {
+        ALOGE("removeUpstreamInterface: Null interface name received");
+        return 0;
+    }
+    for (it = mUpstreamInterfaces->begin(); it != mUpstreamInterfaces->end(); ++it) {
+        if (*it && !strcmp(iface, *it)) {
+            free(*it);
+            mUpstreamInterfaces->erase(it);
+            return removeV6RtrAdvIface(iface);
+        }
+    }
+
+    ALOGW("Couldn't find interface %s to remove", iface);
+    return 0;
+}
+
 NetAddressCollection *TetherController::getDnsForwarders() {
     return mDnsForwarders;
 }
@@ -294,6 +486,8 @@
     }
     mInterfaces->push_back(strdup(interface));
 
+    addV6RtrAdvIface(interface);
+
     if (applyDnsInterfaces()) {
         InterfaceCollection::iterator it;
         for (it = mInterfaces->begin(); it != mInterfaces->end(); ++it) {
@@ -318,7 +512,7 @@
         if (!strcmp(interface, *it)) {
             free(*it);
             mInterfaces->erase(it);
-
+            removeV6RtrAdvIface(NULL);
             return applyDnsInterfaces();
         }
     }
diff --git a/server/TetherController.h b/server/TetherController.h
index 1c32627..64c3e94 100644
--- a/server/TetherController.h
+++ b/server/TetherController.h
@@ -32,6 +32,8 @@
     NetAddressCollection *mDnsForwarders;
     pid_t                 mDaemonPid;
     int                   mDaemonFd;
+    pid_t                 mRtrAdvPid; // IPv6 support
+    InterfaceCollection  *mUpstreamInterfaces;
 
 public:
     TetherController();
@@ -52,6 +54,13 @@
     int tetherInterface(const char *interface);
     int untetherInterface(const char *interface);
     InterfaceCollection *getTetheredInterfaceList();
+    int startV6RtrAdv(int num_ifaces, char **ifaces);
+    int stopV6RtrAdv();
+    bool isV6RtrAdvStarted();
+    int addV6RtrAdvIface(const char *iface);
+    int removeV6RtrAdvIface(const char *iface);
+    int addUpstreamInterface(char *iface);
+    int removeUpstreamInterface(char *iface);
 
 private:
     int applyDnsInterfaces();