DISPATCH-1532 - Reimplemented mobile-address-synchronization as a core module.
diff --git a/include/qpid/dispatch/router_core.h b/include/qpid/dispatch/router_core.h
index bcf5671..5d77004 100644
--- a/include/qpid/dispatch/router_core.h
+++ b/include/qpid/dispatch/router_core.h
@@ -85,18 +85,18 @@
 void qdr_core_remove_next_hop(qdr_core_t *core, int router_maskbit);
 void qdr_core_set_cost(qdr_core_t *core, int router_maskbit, int cost);
 void qdr_core_set_valid_origins(qdr_core_t *core, int router_maskbit, qd_bitmask_t *routers);
-void qdr_core_map_destination(qdr_core_t *core, int router_maskbit, const char *address_hash, int treatment_hint);
-void qdr_core_unmap_destination(qdr_core_t *core, int router_maskbit, const char *address_hash);
+void qdr_core_flush_destinations(qdr_core_t *core, int router_maskbit);
+void qdr_core_mobile_seq_advanced(qdr_core_t *core, int router_maskbit);
 
-typedef void (*qdr_mobile_added_t)   (void *context, const char *address_hash, qd_address_treatment_t treatment);
-typedef void (*qdr_mobile_removed_t) (void *context, const char *address_hash);
-typedef void (*qdr_link_lost_t)      (void *context, int link_maskbit);
+typedef void (*qdr_set_mobile_seq_t)    (void *context, int router_maskbit, uint64_t mobile_seq);
+typedef void (*qdr_set_my_mobile_seq_t) (void *context, uint64_t mobile_seq);
+typedef void (*qdr_link_lost_t)         (void *context, int link_maskbit);
 
-void qdr_core_route_table_handlers(qdr_core_t           *core, 
-                                   void                 *context,
-                                   qdr_mobile_added_t    mobile_added,
-                                   qdr_mobile_removed_t  mobile_removed,
-                                   qdr_link_lost_t       link_lost);
+void qdr_core_route_table_handlers(qdr_core_t              *core, 
+                                   void                    *context,
+                                   qdr_set_mobile_seq_t     set_mobile_seq,
+                                   qdr_set_my_mobile_seq_t  set_my_mobile_seq,
+                                   qdr_link_lost_t          link_lost);
 
 /**
  ******************************************************************************
@@ -106,11 +106,27 @@
 typedef void (*qdr_receive_t) (void *context, qd_message_t *msg, int link_maskbit, int inter_router_cost,
                                uint64_t conn_id);
 
+/**
+ * qdr_core_subscribe
+ *
+ * Subscribe an in-process handler to receive messages to a particular address.
+ *
+ * @param core Pointer to the core module
+ * @param address The address of messages to be received
+ * @param aclass Address class character
+ * @param phase Address phase character ('0' .. '9')
+ * @param treatment Treatment for the address if it be being created as a side effect of this call
+ * @param in_core True iff the handler is to be run in the context of the core thread
+ * @param on_message The handler function
+ * @param context The opaque context sent to the handler on all invocations
+ * @return Pointer to the subscription object
+ */
 qdr_subscription_t *qdr_core_subscribe(qdr_core_t             *core,
                                        const char             *address,
                                        char                    aclass,
                                        char                    phase,
                                        qd_address_treatment_t  treatment,
+                                       bool                    in_core,
                                        qdr_receive_t           on_message,
                                        void                   *context);
 
diff --git a/python/qpid_dispatch_internal/router/engine.py b/python/qpid_dispatch_internal/router/engine.py
index 753d743..e564523 100644
--- a/python/qpid_dispatch_internal/router/engine.py
+++ b/python/qpid_dispatch_internal/router/engine.py
@@ -26,7 +26,6 @@
 from .hello import HelloProtocol
 from .link import LinkStateEngine
 from .path import PathEngine
-from .mobile import MobileAddressEngine
 from .node import NodeTracker
 from .message import Message
 
@@ -56,13 +55,10 @@
         self._config        = None # Not yet loaded
         self._log_hello     = LogAdapter("ROUTER_HELLO")
         self._log_ls        = LogAdapter("ROUTER_LS")
-        self._log_ma        = LogAdapter("ROUTER_MA")
         self._log_general   = LogAdapter("ROUTER")
-        self.io_adapter     = [IoAdapter(self.receive, "qdrouter",    'L', '0', TREATMENT_MULTICAST_FLOOD),
-                               IoAdapter(self.receive, "qdrouter.ma", 'L', '0', TREATMENT_MULTICAST_ONCE),
-                               IoAdapter(self.receive, "qdrouter",    'T', '0', TREATMENT_MULTICAST_FLOOD),
-                               IoAdapter(self.receive, "qdrouter.ma", 'T', '0', TREATMENT_MULTICAST_ONCE),
-                               IoAdapter(self.receive, "qdhello",     'L', '0', TREATMENT_MULTICAST_FLOOD)]
+        self.io_adapter     = [IoAdapter(self.receive, "qdrouter", 'L', '0', TREATMENT_MULTICAST_FLOOD),
+                               IoAdapter(self.receive, "qdrouter", 'T', '0', TREATMENT_MULTICAST_FLOOD),
+                               IoAdapter(self.receive, "qdhello",  'L', '0', TREATMENT_MULTICAST_FLOOD)]
         self.max_routers    = max_routers
         self.id             = router_id
         self.instance       = int(time.time())
@@ -77,7 +73,6 @@
         self.hello_protocol        = HelloProtocol(self, self.node_tracker)
         self.link_state_engine     = LinkStateEngine(self)
         self.path_engine           = PathEngine(self)
-        self.mobile_address_engine = MobileAddressEngine(self, self.node_tracker)
 
 
     ##========================================================================================
@@ -98,26 +93,28 @@
                 raise ValueError("No router configuration found")
         return self._config
 
-    def addressAdded(self, addr, treatment):
-        """
-        """
-        try:
-            if addr[0] in 'MCDEFH':
-                self.mobile_address_engine.add_local_address(addr, treatment)
-        except Exception:
-            self.log_ma(LOG_ERROR, "Exception in new-address processing\n%s" % format_exc(LOG_STACK_LIMIT))
 
-    def addressRemoved(self, addr):
+    def setMobileSeq(self, router_maskbit, mobile_seq):
         """
+        Another router's mobile sequence number has been changed and the Python router needs to store
+        this number.
         """
-        try:
-            if addr[0] in 'MCDEFH':
-                self.mobile_address_engine.del_local_address(addr)
-        except Exception:
-            self.log_ma(LOG_ERROR, "Exception in del-address processing\n%s" % format_exc(LOG_STACK_LIMIT))
+        self.node_tracker.set_mobile_seq(router_maskbit, mobile_seq)
 
+        
+    def setMyMobileSeq(self, mobile_seq):
+        """
+        This router's mobile sequence number has been changed and the Python router needs to store
+        this number and immediately send a router-advertisement message to reflect the change.
+        """
+        self.link_state_engine.set_mobile_seq(mobile_seq)
+        self.link_state_engine.send_ra(time.time())
+
+        
     def linkLost(self, link_id):
         """
+        The control-link to a neighbor has been dropped.  We can cancel the neighbor from the
+        link-state immediately instead of waiting for the hello-timeout to expire.
         """
         self.node_tracker.link_lost(link_id)
 
@@ -133,6 +130,7 @@
         except Exception:
             self.log(LOG_ERROR, "Exception in timer processing\n%s" % format_exc(LOG_STACK_LIMIT))
 
+
     def handleControlMessage(self, opcode, body, link_id, cost):
         """
         """
@@ -158,20 +156,11 @@
                 self.log_ls(LOG_TRACE, "RCVD: %r" % msg)
                 self.link_state_engine.handle_lsr(msg, now)
 
-            elif opcode == 'MAU':
-                msg = MessageMAU(body)
-                self.log_ma(LOG_TRACE, "RCVD: %r" % msg)
-                self.mobile_address_engine.handle_mau(msg, now)
-
-            elif opcode == 'MAR':
-                msg = MessageMAR(body)
-                self.log_ma(LOG_TRACE, "RCVD: %r" % msg)
-                self.mobile_address_engine.handle_mar(msg, now)
-
         except Exception:
             self.log(LOG_ERROR, "Exception in control message processing\n%s" % format_exc(LOG_STACK_LIMIT))
             self.log(LOG_ERROR, "Control message error: opcode=%s body=%r" % (opcode, body))
 
+
     def receive(self, message, link_id, cost):
         """
         This is the IoAdapter message-receive handler
@@ -183,6 +172,7 @@
             self.log(LOG_ERROR, "Exception in raw message processing: properties=%r body=%r" %
                      (message.properties, message.body))
 
+
     def getRouterData(self, kind):
         """
         """
diff --git a/python/qpid_dispatch_internal/router/mobile.py b/python/qpid_dispatch_internal/router/mobile.py
deleted file mode 100644
index e6ee48e..0000000
--- a/python/qpid_dispatch_internal/router/mobile.py
+++ /dev/null
@@ -1,175 +0,0 @@
-#
-# Licensed to the Apache Software Foundation (ASF) under one
-# or more contributor license agreements.  See the NOTICE file
-# distributed with this work for additional information
-# regarding copyright ownership.  The ASF licenses this file
-# to you under the Apache License, Version 2.0 (the
-# "License"); you may not use this file except in compliance
-# with the License.  You may obtain a copy of the License at
-#
-#   http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing,
-# software distributed under the License is distributed on an
-# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-# KIND, either express or implied.  See the License for the
-# specific language governing permissions and limitations
-# under the License.
-#
-
-from __future__ import unicode_literals
-from __future__ import division
-from __future__ import absolute_import
-from __future__ import print_function
-
-from .data import MessageMAR, MessageMAU
-from ..dispatch import LOG_TRACE
-
-MAX_KEPT_DELTAS = 10
-
-class MobileAddressEngine(object):
-    """
-    This module is responsible for maintaining an up-to-date list of mobile addresses in the domain.
-    It runs the Mobile-Address protocol and generates an un-optimized routing table for mobile addresses.
-    Note that this routing table maps from the mobile address to the remote router where that address
-    is directly bound.
-    """
-    def __init__(self, container, node_tracker):
-        self.container     = container
-        self.node_tracker  = node_tracker
-        self.id            = self.container.id
-        self.mobile_seq    = 0
-        self.local_addrs   = set([])
-        self.added_addrs   = set([])
-        self.deleted_addrs = set([])
-        self.sent_deltas   = {}
-        self.treatments    = {}
-
-
-    def tick(self, now):
-        ##
-        ## If local addrs have changed, collect the changes and send a MAU with the diffs
-        ## Note: it is important that the differential-MAU be sent before a RA is sent
-        ##
-        if len(self.added_addrs) > 0 or len(self.deleted_addrs) > 0:
-            self.mobile_seq += 1
-            hints = [self.treatments[a] for a in self.added_addrs]
-            msg = MessageMAU(None, self.id, self.mobile_seq, list(self.added_addrs), list(self.deleted_addrs), _hints=hints)
-
-            self.sent_deltas[self.mobile_seq] = msg
-            if len(self.sent_deltas) > MAX_KEPT_DELTAS:
-                self.sent_deltas.pop(self.mobile_seq - MAX_KEPT_DELTAS)
-
-            self.container.send('amqp:/_topo/0/all/qdrouter.ma', msg)
-            self.container.log_ma(LOG_TRACE, "SENT: %r" % msg)
-            self.local_addrs.update(self.added_addrs)
-            self.local_addrs.difference_update(self.deleted_addrs)
-            self.added_addrs.clear()
-            self.deleted_addrs.clear()
-        return self.mobile_seq
-
-
-    def add_local_address(self, addr, treatment):
-        """
-        """
-        self.treatments[addr] = treatment
-        if addr not in self.local_addrs:
-            if addr not in self.added_addrs:
-                self.added_addrs.add(addr)
-        else:
-            if addr in self.deleted_addrs:
-                self.deleted_addrs.remove(addr)
-
-
-    def del_local_address(self, addr):
-        """
-        """
-        del self.treatments[addr]
-        if addr in self.local_addrs:
-            if addr not in self.deleted_addrs:
-                self.deleted_addrs.add(addr)
-        else:
-            if addr in self.added_addrs:
-                self.added_addrs.remove(addr)
-
-
-    def handle_mau(self, msg, now):
-        ##
-        ## If the MAU is differential, we can only use it if its sequence is exactly one greater
-        ## than our stored sequence.  If not, we will ignore the content and schedule a MAR.
-        ##
-        ## If the MAU is absolute, we can use it in all cases.
-        ##
-        if msg.id == self.id:
-            return
-        node = self.node_tracker.router_node(msg.id)
-
-        if msg.exist_list != None:
-            ##
-            ## Absolute MAU
-            ##
-            if msg.mobile_seq == node.mobile_address_sequence:
-                return
-            node.mobile_address_sequence = msg.mobile_seq
-            node.overwrite_addresses(msg.exist_list)
-        else:
-            ##
-            ## Differential MAU
-            ##
-            if node.mobile_address_sequence + 1 == msg.mobile_seq:
-                ##
-                ## This message represents the next expected sequence, incorporate the deltas
-                ##
-                node.mobile_address_sequence += 1
-                treatments = msg.hints or []
-                for a in msg.add_list:
-                    if len(treatments):
-                        treatment = treatments.pop(0)
-                    else:
-                        treatment = -1
-                    node.map_address(a, treatment)
-                for a in msg.del_list:
-                    node.unmap_address(a)
-
-            elif node.mobile_address_sequence == msg.mobile_seq:
-                ##
-                ## Ignore duplicates
-                ##
-                return
-
-            else:
-                ##
-                ## This is an out-of-sequence delta.  Don't use it.  Schedule a MAR to
-                ## get back on track.
-                ##
-                node.mobile_address_request()
-
-
-    def handle_mar(self, msg, now):
-        if msg.id == self.id:
-            return
-        if msg.have_seq == self.mobile_seq:
-            return
-        if self.mobile_seq - (msg.have_seq + 1) < len(self.sent_deltas):
-            ##
-            ## We can catch the peer up with a series of stored differential updates
-            ##
-            for s in range(msg.have_seq + 1, self.mobile_seq + 1):
-                self.container.send('amqp:/_topo/0/%s/qdrouter.ma' % msg.id, self.sent_deltas[s])
-                self.container.log_ma(LOG_TRACE, "SENT: %r" % self.sent_deltas[s])
-            return
-
-        ##
-        ## The peer needs to be sent an absolute update with the whole address list
-        ##
-        smsg = MessageMAU(None, self.id, self.mobile_seq, None, None, list(self.local_addrs))
-        self.container.send('amqp:/_topo/0/%s/qdrouter.ma' % msg.id, smsg)
-        self.container.log_ma(LOG_TRACE, "SENT: %r" % smsg)
-
-
-    def send_mar(self, node_id, seq):
-        msg = MessageMAR(None, self.id, seq)
-        self.container.send('amqp:/_topo/0/%s/qdrouter.ma' % node_id, msg)
-        self.container.log_ma(LOG_TRACE, "SENT: %r" % msg)
-
-
diff --git a/python/qpid_dispatch_internal/router/node.py b/python/qpid_dispatch_internal/router/node.py
index c99ce95..aed6870 100644
--- a/python/qpid_dispatch_internal/router/node.py
+++ b/python/qpid_dispatch_internal/router/node.py
@@ -187,14 +187,7 @@
             if node.link_state_requested():
                 self.container.link_state_engine.send_lsr(node_id)
             if node.mobile_address_requested():
-                self.container.mobile_address_engine.send_mar(node_id, node.mobile_address_sequence)
-
-        ##
-        ## If local changes have been made to the list of mobile addresses, send
-        ## an unsolicited mobile-address-update to all routers.
-        ##
-        mobile_seq = self.container.mobile_address_engine.tick(now)
-        self.container.link_state_engine.set_mobile_seq(mobile_seq)
+                self.container.router_adapter.mobile_seq_advanced(node.maskbit)
 
         ##
         ## Send an immediate RA if our link state changed
@@ -260,6 +253,15 @@
                 self.link_state_changed = True
 
 
+    def set_mobile_seq(self, router_maskbit, mobile_seq):
+        """
+        """
+        for node in self.nodes.values():
+            if node.maskbit == router_maskbit:
+                node.mobile_address_sequence = mobile_seq
+                return
+
+
     def in_flux_mode(self, now):
         result = (now - self.last_topology_change) <= self.flux_interval
         if not result and self.flux_mode:
@@ -406,7 +408,6 @@
         self.next_hop_router         = None
         self.cost                    = None
         self.valid_origins           = None
-        self.mobile_addresses        = set([])
         self.mobile_address_sequence = 0
         self.need_ls_request         = True
         self.need_mobile_request     = False
@@ -541,34 +542,10 @@
         return False
 
 
-    def map_address(self, addr, treatment = -1):
-        self.mobile_addresses.add(addr)
-        self.adapter.map_destination(addr, treatment, self.maskbit)
-        self.log(LOG_DEBUG, "Remote destination %s mapped to router %s" % (self._logify(addr), self.id))
-
-
-    def unmap_address(self, addr):
-        self.mobile_addresses.remove(addr)
-        self.adapter.unmap_destination(addr, self.maskbit)
-        self.log(LOG_DEBUG, "Remote destination %s unmapped from router %s" % (self._logify(addr), self.id))
-
-
     def unmap_all_addresses(self):
         self.mobile_address_sequence = 0
-        for addr in self.mobile_addresses:
-            self.adapter.unmap_destination(addr, self.maskbit)
-            self.log(LOG_DEBUG, "Remote destination %s unmapped from router %s" % (self._logify(addr), self.id))
-
-    def overwrite_addresses(self, addrs_list):
-        added   = []
-        deleted = []
-        addrs = set(addrs_list)
-        added = addrs.difference(self.mobile_addresses)
-        deleted = self.mobile_addresses.difference(addrs)
-        for a in added:
-            self.map_address(a)
-        for a in deleted:
-            self.unmap_address(a)
+        self.adapter.flush_destinations(self.maskbit)
+        self.log(LOG_DEBUG, "Remote destinations flushed from router %s" % (self.id))
 
 
     def update_instance(self, instance, version):
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index d57df77..0a01d43 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -100,6 +100,7 @@
   router_core/modules/address_lookup_server/address_lookup_server.c
   router_core/modules/address_lookup_client/lookup_client.c
   router_core/modules/stuck_delivery_detection/delivery_tracker.c
+  router_core/modules/mobile_sync/mobile.c
   router_node.c
   router_pynode.c
   schema_enum.c
diff --git a/src/parse.c b/src/parse.c
index 087b8d5..25d303d 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -676,7 +676,9 @@
     if (!field)
         return 0;
 
-    return field->tag == QD_AMQP_LIST8 || field->tag == QD_AMQP_LIST32;
+    return field->tag == QD_AMQP_LIST8
+        || field->tag == QD_AMQP_LIST32
+        || field->tag == QD_AMQP_LIST0;
 }
 
 
diff --git a/src/python_embedded.c b/src/python_embedded.c
index 154ee00..972a235 100644
--- a/src/python_embedded.c
+++ b/src/python_embedded.c
@@ -587,7 +587,8 @@
     char *address = py_string_2_c(addr);
     if (!address) return -1;
     qd_error_clear();
-    self->sub = qdr_core_subscribe(self->core, address, aclass, phase, treatment, qd_io_rx_handler, self);
+    self->sub = qdr_core_subscribe(self->core, address, aclass, phase, treatment,
+                                   false, qd_io_rx_handler, self);
     free(address);
     if (qd_error_code()) {
         PyErr_SetString(PyExc_RuntimeError, qd_error_message());
diff --git a/src/router_core/connections.c b/src/router_core/connections.c
index 0a710d0..1a44baf 100644
--- a/src/router_core/connections.c
+++ b/src/router_core/connections.c
@@ -1249,7 +1249,6 @@
         && DEQ_SIZE(addr->inlinks) == 0
         && qd_bitmask_cardinality(addr->rnodes) == 0
         && addr->ref_count == 0
-        && !addr->block_deletion
         && addr->tracked_deliveries == 0
         && addr->core_endpoint == 0
         && addr->fallback_for == 0) {
@@ -1767,7 +1766,7 @@
         return;
     }
 
-    qdr_address_t    *addr  = link->owning_addr;
+    qdr_address_t *addr = link->owning_addr;
 
     if (link->detach_received)
         return;
@@ -1839,7 +1838,9 @@
                     //
                     // Unbind the address and the link.
                     //
+                    addr->ref_count++;
                     qdr_core_unbind_address_link_CT(core, addr, link);
+                    addr->ref_count--;
 
                     //
                     // If this is an edge data link, raise a link event to indicate its detachment.
@@ -1865,8 +1866,11 @@
             switch (link->link_type) {
             case QD_LINK_ENDPOINT:
             case QD_LINK_EDGE_DOWNLINK:
-                if (addr)
+                if (addr) {
+                    addr->ref_count++;
                     qdr_core_unbind_address_link_CT(core, addr, link);
+                    addr->ref_count--;
+                }
                 break;
 
             case QD_LINK_CONTROL:
diff --git a/src/router_core/core_events.c b/src/router_core/core_events.c
index 34e7b5f..bbdc1c0 100644
--- a/src/router_core/core_events.c
+++ b/src/router_core/core_events.c
@@ -21,14 +21,16 @@
 
 
 struct qdrc_event_subscription_t {
-    DEQ_LINKS_N(CONN, qdrc_event_subscription_t);
-    DEQ_LINKS_N(LINK, qdrc_event_subscription_t);
-    DEQ_LINKS_N(ADDR, qdrc_event_subscription_t);
+    DEQ_LINKS_N(CONN,   qdrc_event_subscription_t);
+    DEQ_LINKS_N(LINK,   qdrc_event_subscription_t);
+    DEQ_LINKS_N(ADDR,   qdrc_event_subscription_t);
+    DEQ_LINKS_N(ROUTER, qdrc_event_subscription_t);
     void                    *context;
     qdrc_event_t             events;
     qdrc_connection_event_t  on_conn_event;
     qdrc_link_event_t        on_link_event;
     qdrc_address_event_t     on_addr_event;
+    qdrc_router_event_t      on_router_event;
 };
 
 
@@ -37,21 +39,24 @@
                                                    qdrc_connection_event_t on_conn_event,
                                                    qdrc_link_event_t       on_link_event,
                                                    qdrc_address_event_t    on_addr_event,
+                                                   qdrc_router_event_t     on_router_event,
                                                    void                   *context)
 {
     qdrc_event_subscription_t *sub = NEW(qdrc_event_subscription_t);
     ZERO(sub);
 
-    sub->context       = context;
-    sub->events        = events;
-    sub->on_conn_event = on_conn_event;
-    sub->on_link_event = on_link_event;
-    sub->on_addr_event = on_addr_event;
+    sub->context         = context;
+    sub->events          = events;
+    sub->on_conn_event   = on_conn_event;
+    sub->on_link_event   = on_link_event;
+    sub->on_addr_event   = on_addr_event;
+    sub->on_router_event = on_router_event;
 
-    assert((events & ~(_QDRC_EVENT_CONN_RANGE | _QDRC_EVENT_LINK_RANGE | _QDRC_EVENT_ADDR_RANGE)) == 0);
-    assert(!(events & _QDRC_EVENT_CONN_RANGE) || on_conn_event);
-    assert(!(events & _QDRC_EVENT_LINK_RANGE) || on_link_event);
-    assert(!(events & _QDRC_EVENT_ADDR_RANGE) || on_addr_event);
+    assert((events & ~(_QDRC_EVENT_CONN_RANGE | _QDRC_EVENT_LINK_RANGE | _QDRC_EVENT_ADDR_RANGE | _QDRC_EVENT_ROUTER_RANGE)) == 0);
+    assert(!(events & _QDRC_EVENT_CONN_RANGE)   || on_conn_event);
+    assert(!(events & _QDRC_EVENT_LINK_RANGE)   || on_link_event);
+    assert(!(events & _QDRC_EVENT_ADDR_RANGE)   || on_addr_event);
+    assert(!(events & _QDRC_EVENT_ROUTER_RANGE) || on_router_event);
 
     if (events & _QDRC_EVENT_CONN_RANGE)
         DEQ_INSERT_TAIL_N(CONN, core->conn_event_subscriptions, sub);
@@ -62,6 +67,9 @@
     if (events & _QDRC_EVENT_ADDR_RANGE)
         DEQ_INSERT_TAIL_N(ADDR, core->addr_event_subscriptions, sub);
 
+    if (events & _QDRC_EVENT_ROUTER_RANGE)
+        DEQ_INSERT_TAIL_N(ROUTER, core->router_event_subscriptions, sub);
+
     return sub;
 }
 
@@ -77,6 +85,9 @@
     if (sub->events & _QDRC_EVENT_ADDR_RANGE)
         DEQ_REMOVE_N(ADDR, core->addr_event_subscriptions, sub);
 
+    if (sub->events & _QDRC_EVENT_ROUTER_RANGE)
+        DEQ_REMOVE_N(ROUTER, core->router_event_subscriptions, sub);
+
     free(sub);
 }
 
@@ -116,3 +127,15 @@
     }
 }
 
+
+void qdrc_event_router_raise(qdr_core_t *core, qdrc_event_t event, qdr_node_t *router)
+{
+    qdrc_event_subscription_t *sub = DEQ_HEAD(core->router_event_subscriptions);
+
+    while (sub) {
+        if (sub->events & event)
+            sub->on_router_event(sub->context, event, router);
+        sub = DEQ_NEXT_N(ROUTER, sub);
+    }
+}
+
diff --git a/src/router_core/core_events.h b/src/router_core/core_events.h
index 67f2fca..7b351c0 100644
--- a/src/router_core/core_events.h
+++ b/src/router_core/core_events.h
@@ -60,6 +60,11 @@
  * QDRC_EVENT_ADDR_NO_LONGER_SOURCE      An address transitioned from one to zero local sources (inlink)
  * QDRC_EVENT_ADDR_TWO_SOURCE            An address transitioned from one to two local sources (inlink)
  * QDRC_EVENT_ADDR_ONE_SOURCE            An address transitioned from two to one local sources (inlink)
+ *
+ * QDRC_EVENT_ROUTER_ADDED               A remote router has been discovered
+ * QDRC_EVENT_ROUTER_REMOVED             A remote router has been lost
+ * QDRC_EVENT_ROUTER_MOBILE_FLUSH        A remote router needs its mobile addresses unmapped
+ * QDRC_EVENT_ROUTER_MOBILE_SEQ_ADVANCED A remote router's mobile sequence advanced past our version of the sequence
 */
 
 #define QDRC_EVENT_CONN_OPENED               0x00000001
@@ -70,27 +75,33 @@
 #define QDRC_EVENT_CONN_IR_LOST              0x00000020
 #define _QDRC_EVENT_CONN_RANGE               0x0000003F
 
-#define QDRC_EVENT_LINK_IN_ATTACHED          0x00000100
-#define QDRC_EVENT_LINK_IN_DETACHED          0x00000200
-#define QDRC_EVENT_LINK_OUT_ATTACHED         0x00000400
-#define QDRC_EVENT_LINK_OUT_DETACHED         0x00000800
-#define QDRC_EVENT_LINK_EDGE_DATA_ATTACHED   0x00001000
-#define QDRC_EVENT_LINK_EDGE_DATA_DETACHED   0x00002000
-#define _QDRC_EVENT_LINK_RANGE               0x00003F00
+#define QDRC_EVENT_LINK_IN_ATTACHED          0x00000040
+#define QDRC_EVENT_LINK_IN_DETACHED          0x00000080
+#define QDRC_EVENT_LINK_OUT_ATTACHED         0x00000100
+#define QDRC_EVENT_LINK_OUT_DETACHED         0x00000200
+#define QDRC_EVENT_LINK_EDGE_DATA_ATTACHED   0x00000400
+#define QDRC_EVENT_LINK_EDGE_DATA_DETACHED   0x00000800
+#define _QDRC_EVENT_LINK_RANGE               0x00000FC0
 
-#define QDRC_EVENT_ADDR_ADDED                0x00010000
-#define QDRC_EVENT_ADDR_REMOVED              0x00020000
-#define QDRC_EVENT_ADDR_BECAME_LOCAL_DEST    0x00040000
-#define QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST 0x00080000
-#define QDRC_EVENT_ADDR_BECAME_DEST          0x00100000
-#define QDRC_EVENT_ADDR_NO_LONGER_DEST       0x00200000
-#define QDRC_EVENT_ADDR_ONE_LOCAL_DEST       0x00400000
-#define QDRC_EVENT_ADDR_TWO_DEST             0x00800000
-#define QDRC_EVENT_ADDR_BECAME_SOURCE        0x01000000
-#define QDRC_EVENT_ADDR_NO_LONGER_SOURCE     0x02000000
-#define QDRC_EVENT_ADDR_TWO_SOURCE           0x04000000
-#define QDRC_EVENT_ADDR_ONE_SOURCE           0x08000000
-#define _QDRC_EVENT_ADDR_RANGE               0x0FFF0000
+#define QDRC_EVENT_ADDR_ADDED                0x00001000
+#define QDRC_EVENT_ADDR_REMOVED              0x00002000
+#define QDRC_EVENT_ADDR_BECAME_LOCAL_DEST    0x00004000
+#define QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST 0x00008000
+#define QDRC_EVENT_ADDR_BECAME_DEST          0x00010000
+#define QDRC_EVENT_ADDR_NO_LONGER_DEST       0x00020000
+#define QDRC_EVENT_ADDR_ONE_LOCAL_DEST       0x00040000
+#define QDRC_EVENT_ADDR_TWO_DEST             0x00080000
+#define QDRC_EVENT_ADDR_BECAME_SOURCE        0x00100000
+#define QDRC_EVENT_ADDR_NO_LONGER_SOURCE     0x00200000
+#define QDRC_EVENT_ADDR_TWO_SOURCE           0x00400000
+#define QDRC_EVENT_ADDR_ONE_SOURCE           0x00800000
+#define _QDRC_EVENT_ADDR_RANGE               0x00FFF000
+
+#define QDRC_EVENT_ROUTER_ADDED               0x01000000
+#define QDRC_EVENT_ROUTER_REMOVED             0x02000000
+#define QDRC_EVENT_ROUTER_MOBILE_FLUSH        0x04000000
+#define QDRC_EVENT_ROUTER_MOBILE_SEQ_ADVANCED 0x08000000
+#define _QDRC_EVENT_ROUTER_RANGE              0x0F000000
 
 
 /**
@@ -112,6 +123,10 @@
                                       qdrc_event_t   event_type,
                                       qdr_address_t *addr);
 
+typedef void (*qdrc_router_event_t) (void          *context,
+                                     qdrc_event_t   event_type,
+                                     qdr_node_t    *router);
+
 /**
  * qdrc_event_subscribe_CT
  *
@@ -130,6 +145,7 @@
                                                    qdrc_connection_event_t on_conn_event,
                                                    qdrc_link_event_t       on_link_event,
                                                    qdrc_address_event_t    on_addr_event,
+                                                   qdrc_router_event_t     on_router_event,
                                                    void                   *context);
 
 /**
@@ -152,5 +168,6 @@
 void qdrc_event_conn_raise(qdr_core_t *core, qdrc_event_t event, qdr_connection_t *conn);
 void qdrc_event_link_raise(qdr_core_t *core, qdrc_event_t event, qdr_link_t *link);
 void qdrc_event_addr_raise(qdr_core_t *core, qdrc_event_t event, qdr_address_t *addr);
+void qdrc_event_router_raise(qdr_core_t *core, qdrc_event_t event, qdr_node_t *router);
 
 #endif
diff --git a/src/router_core/delivery.c b/src/router_core/delivery.c
index 6d98673..7471716 100644
--- a/src/router_core/delivery.c
+++ b/src/router_core/delivery.c
@@ -448,6 +448,15 @@
     qdr_delivery_increment_counters_CT(core, delivery);
 
     //
+    // Remove any subscription references
+    //
+    qdr_subscription_ref_t *sub = DEQ_HEAD(delivery->subscriptions);
+    while (sub) {
+        qdr_del_subscription_ref_CT(&delivery->subscriptions, sub);
+        sub = DEQ_HEAD(delivery->subscriptions);
+    }
+
+    //
     // Free all the peer qdr_delivery_ref_t references
     //
     qdr_delivery_ref_t *ref = DEQ_HEAD(delivery->peers);
@@ -1063,11 +1072,11 @@
             // The entire message has now been received. Check to see if there are in process subscriptions that need to
             // receive this message. in process subscriptions, at this time, can deal only with full messages.
             //
-            qdr_subscription_t *sub = DEQ_HEAD(in_dlv->subscriptions);
-            while (sub) {
-                DEQ_REMOVE_HEAD(in_dlv->subscriptions);
-                qdr_forward_on_message_CT(core, sub, link, in_dlv->msg);
-                sub = DEQ_HEAD(in_dlv->subscriptions);
+            qdr_subscription_ref_t *subref = DEQ_HEAD(in_dlv->subscriptions);
+            while (subref) {
+                qdr_forward_on_message_CT(core, subref->sub, link, in_dlv->msg);
+                qdr_del_subscription_ref_CT(&in_dlv->subscriptions, subref);
+                subref = DEQ_HEAD(in_dlv->subscriptions);
             }
 
             // This is a presettled multi-frame unicast delivery.
diff --git a/src/router_core/delivery.h b/src/router_core/delivery.h
index 3e93970..ac29739 100644
--- a/src/router_core/delivery.h
+++ b/src/router_core/delivery.h
@@ -59,7 +59,7 @@
     int                     tracking_addr_bit;
     int                     ingress_index;
     qdr_link_work_t        *link_work;         ///< Delivery work item for this delivery
-    qdr_subscription_list_t subscriptions;
+    qdr_subscription_ref_list_t subscriptions;
     qdr_delivery_ref_list_t peers;             /// Use this list if there if the delivery has more than one peer.
     bool                    multicast;         /// True if this delivery is targeted for a multicast address.
     bool                    via_edge;          /// True if this delivery arrived via an edge-connection.
diff --git a/src/router_core/exchange_bindings.c b/src/router_core/exchange_bindings.c
index dc3b495..5bf1bbb 100644
--- a/src/router_core/exchange_bindings.c
+++ b/src/router_core/exchange_bindings.c
@@ -928,9 +928,11 @@
             ex->alternate = next_hop(ex, alternate, alt_phase);
         }
 
-        qdr_post_mobile_added_CT(core,
-                                 (const char*) qd_hash_key_by_handle(ex->qdr_addr->hash_handle),
-                                 ex->qdr_addr->treatment);
+        //
+        // TODO - handle case where there was already a local dest.
+        //
+        qdr_addr_start_inlinks_CT(ex->core, ex->qdr_addr);
+        qdrc_event_addr_raise(ex->core, QDRC_EVENT_ADDR_BECAME_LOCAL_DEST, ex->qdr_addr);
     }
 
     return ex;
@@ -939,8 +941,7 @@
 static void qdr_exchange_free(qdr_exchange_t *ex)
 {
     if (ex->core->running && DEQ_SIZE(ex->qdr_addr->rlinks) == 0) {
-        qdr_post_mobile_removed_CT(ex->core,
-                                   (const char*) qd_hash_key_by_handle(ex->qdr_addr->hash_handle));
+        qdrc_event_addr_raise(ex->core, QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST, ex->qdr_addr);
     }
 
     DEQ_REMOVE(ex->core->exchanges, ex);
diff --git a/src/router_core/forwarder.c b/src/router_core/forwarder.c
index ab73501..52e479a 100644
--- a/src/router_core/forwarder.c
+++ b/src/router_core/forwarder.c
@@ -269,14 +269,28 @@
 
 void qdr_forward_on_message_CT(qdr_core_t *core, qdr_subscription_t *sub, qdr_link_t *link, qd_message_t *msg)
 {
-    qdr_general_work_t *work = qdr_general_work(qdr_forward_on_message);
-    work->on_message         = sub->on_message;
-    work->on_message_context = sub->on_message_context;
-    work->msg                = qd_message_copy(msg);
-    work->maskbit            = link ? link->conn->mask_bit : 0;
-    work->inter_router_cost  = link ? link->conn->inter_router_cost : 1;
-    work->in_conn_id         = link ? link->conn->identity : 0;
-    qdr_post_general_work_CT(core, work);
+    int      mask_bit = link ? link->conn->mask_bit : 0;
+    int      cost     = link ? link->conn->inter_router_cost : 1;
+    uint64_t identity = link ? link->conn->identity : 0;
+
+    if (sub->in_core) {
+        //
+        // The handler runs in-core.  Invoke it right now.
+        //
+        sub->on_message(sub->on_message_context, msg, mask_bit, cost, identity);
+    } else {
+        //
+        // The handler runs in an IO thread.  Defer its invocation.
+        //
+        qdr_general_work_t *work = qdr_general_work(qdr_forward_on_message);
+        work->on_message         = sub->on_message;
+        work->on_message_context = sub->on_message_context;
+        work->msg                = qd_message_copy(msg);
+        work->maskbit            = mask_bit;
+        work->inter_router_cost  = cost;
+        work->in_conn_id         = identity;
+        qdr_post_general_work_CT(core, work);
+    }
 }
 
 
@@ -327,7 +341,7 @@
         // after the message fully arrives
         //
         assert(in_dlv);
-        DEQ_INSERT_TAIL(in_dlv->subscriptions, sub);
+        qdr_add_subscription_ref_CT(&in_dlv->subscriptions, sub);
         qd_message_Q2_holdoff_disable(in_msg);
     }
 }
diff --git a/src/router_core/modules/address_lookup_client/lookup_client.c b/src/router_core/modules/address_lookup_client/lookup_client.c
index ba4ffd8..aa6f968 100644
--- a/src/router_core/modules/address_lookup_client/lookup_client.c
+++ b/src/router_core/modules/address_lookup_client/lookup_client.c
@@ -774,7 +774,7 @@
     client->core      = core;
     client->event_sub = qdrc_event_subscribe_CT(client->core,
                                                 QDRC_EVENT_CONN_EDGE_ESTABLISHED | QDRC_EVENT_CONN_EDGE_LOST,
-                                                on_conn_event, 0, 0,
+                                                on_conn_event, 0, 0, 0,
                                                 client);
 
     core->addr_lookup_handler = qcm_addr_lookup_CT;
diff --git a/src/router_core/modules/edge_addr_tracking/edge_addr_tracking.c b/src/router_core/modules/edge_addr_tracking/edge_addr_tracking.c
index c89a9cf..2fa7bff 100644
--- a/src/router_core/modules/edge_addr_tracking/edge_addr_tracking.c
+++ b/src/router_core/modules/edge_addr_tracking/edge_addr_tracking.c
@@ -407,6 +407,7 @@
             0,
             on_link_event,
             on_addr_event,
+            0,
             context);
 }
 
diff --git a/src/router_core/modules/edge_router/addr_proxy.c b/src/router_core/modules/edge_router/addr_proxy.c
index 22998be..af6e5c2 100644
--- a/src/router_core/modules/edge_router/addr_proxy.c
+++ b/src/router_core/modules/edge_router/addr_proxy.c
@@ -526,7 +526,8 @@
                                             on_conn_event,
                                             0,
                                             on_addr_event,
-                                            ap);
+                                            0,
+                                            ap);                                            
 
     core->edge_conn_addr = qcm_edge_conn_addr;
     core->edge_context = ap;
diff --git a/src/router_core/modules/edge_router/connection_manager.c b/src/router_core/modules/edge_router/connection_manager.c
index bb4ae1c..76cfd6c 100644
--- a/src/router_core/modules/edge_router/connection_manager.c
+++ b/src/router_core/modules/edge_router/connection_manager.c
@@ -98,6 +98,7 @@
                                             on_conn_event,
                                             0,
                                             0,
+                                            0,
                                             cm);
     cm->active_edge_connection = 0;
 
diff --git a/src/router_core/modules/edge_router/edge_mgmt.c b/src/router_core/modules/edge_router/edge_mgmt.c
index beee1c5..84cb9a2 100644
--- a/src/router_core/modules/edge_router/edge_mgmt.c
+++ b/src/router_core/modules/edge_router/edge_mgmt.c
@@ -303,8 +303,9 @@
                                             (QDRC_EVENT_CONN_EDGE_ESTABLISHED
                                              | QDRC_EVENT_CONN_EDGE_LOST),
                                             _conn_event_CT,
-                                            NULL,  // link event
-                                            NULL,  // addr event
+                                            0,     // link event
+                                            0,     // addr event
+                                            0,     // router event
                                             core); // context
 }
 
diff --git a/src/router_core/modules/edge_router/link_route_proxy.c b/src/router_core/modules/edge_router/link_route_proxy.c
index 0e8cb7e..d21d23d 100644
--- a/src/router_core/modules/edge_router/link_route_proxy.c
+++ b/src/router_core/modules/edge_router/link_route_proxy.c
@@ -462,8 +462,9 @@
                                              | QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST
                                              | QDRC_EVENT_ADDR_BECAME_LOCAL_DEST),
                                             _on_conn_event,
-                                            NULL,
+                                            0,
                                             _on_addr_event,
+                                            0,
                                             core);
 }
 
diff --git a/src/router_core/modules/mobile_sync/mobile.c b/src/router_core/modules/mobile_sync/mobile.c
new file mode 100644
index 0000000..5055f2f
--- /dev/null
+++ b/src/router_core/modules/mobile_sync/mobile.c
@@ -0,0 +1,892 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "module.h"
+#include "router_core_private.h"
+#include "core_events.h"
+#include "route_control.h"
+#include <qpid/dispatch/ctools.h>
+#include <qpid/dispatch/log.h>
+#include <qpid/dispatch/compose.h>
+#include <qpid/dispatch/message.h>
+#include <qpid/dispatch/router.h>
+#include <stdio.h>
+#include <inttypes.h>
+
+#define PROTOCOL_VERSION 1
+static const char *OPCODE     = "opcode";
+static const char *MAR        = "MAR";
+static const char *MAU        = "MAU";
+static const char *ID         = "id";
+static const char *PV         = "pv";
+static const char *AREA       = "area";
+static const char *MOBILE_SEQ = "mobile_seq";
+static const char *HINTS      = "hints";
+static const char *ADD        = "add";
+static const char *DEL        = "del";
+static const char *EXIST      = "exist";
+static const char *HAVE_SEQ   = "have_seq";
+
+//
+// Address.sync_mask bit values
+//
+#define ADDR_SYNC_IN_ADD_LIST           0x00000001
+#define ADDR_SYNC_IN_DEL_LIST           0x00000002
+#define ADDR_SYNC_TO_BE_DELETED         0x00000004
+#define ADDR_SYNC_MOBILE_TRACKING       0x00000008
+
+#define BIT_SET(M,B)   M |= B
+#define BIT_CLEAR(M,B) M &= ~B
+#define BIT_IS_SET(M,B) (M & B)
+
+typedef struct {
+    qdr_core_t                *core;
+    qdrc_event_subscription_t *event_sub;
+    qdr_core_timer_t          *timer;
+    qdr_subscription_t        *message_sub1;
+    qdr_subscription_t        *message_sub2;
+    qd_log_source_t           *log;
+    uint64_t                   mobile_seq;
+    qdr_address_list_t         added_addrs;
+    qdr_address_list_t         deleted_addrs;
+} qdrm_mobile_sync_t;
+
+
+//================================================================================
+// Helper Functions
+//================================================================================
+
+static qd_address_treatment_t qcm_mobile_sync_default_treatment(qdr_core_t *core, int hint) {
+    switch (hint) {
+    case QD_TREATMENT_MULTICAST_FLOOD:
+        return QD_TREATMENT_MULTICAST_FLOOD;
+    case QD_TREATMENT_MULTICAST_ONCE:
+        return QD_TREATMENT_MULTICAST_ONCE;
+    case QD_TREATMENT_ANYCAST_CLOSEST:
+        return QD_TREATMENT_ANYCAST_CLOSEST;
+    case QD_TREATMENT_ANYCAST_BALANCED:
+        return QD_TREATMENT_ANYCAST_BALANCED;
+    case QD_TREATMENT_LINK_BALANCED:
+        return QD_TREATMENT_LINK_BALANCED;
+    case QD_TREATMENT_UNAVAILABLE:
+        return QD_TREATMENT_UNAVAILABLE;
+    default:
+        return core->qd->default_treatment == QD_TREATMENT_UNAVAILABLE ? QD_TREATMENT_ANYCAST_BALANCED : core->qd->default_treatment;
+    }
+}
+
+
+static bool qcm_mobile_sync_addr_is_mobile(qdr_address_t *addr)
+{
+    const char *hash_key = (const char*) qd_hash_key_by_handle(addr->hash_handle);
+    return !!strchr("MCDEFH", hash_key[0]);
+}
+
+
+qdr_node_t *qdc_mobile_sync_router_by_id(qdrm_mobile_sync_t *msync, qd_parsed_field_t *id_field)
+{
+    qd_iterator_t *id_iter = qd_parse_raw(id_field);
+    qdr_node_t *router = DEQ_HEAD(msync->core->routers);
+    while (!!router) {
+        if (qd_iterator_equal(id_iter, qd_hash_key_by_handle(router->owning_addr->hash_handle) + 1))
+            return router;
+        router = DEQ_NEXT(router);
+    }
+
+    return 0;
+}
+
+
+/**
+ * Bump the ref_count on the address to ensure it is not deleted out from under our attention.
+ */
+static void qcm_mobile_sync_start_tracking(qdr_address_t *addr)
+{
+    BIT_SET(addr->sync_mask, ADDR_SYNC_MOBILE_TRACKING);
+    addr->ref_count++;
+}
+
+
+/**
+ * Decrement the address's ref_count.
+ * Check the address to have it deleted if it is no longer referenced anywhere.
+ */
+static void qcm_mobile_sync_stop_tracking(qdr_core_t *core, qdr_address_t *addr)
+{
+    BIT_CLEAR(addr->sync_mask, ADDR_SYNC_MOBILE_TRACKING);
+    if (--addr->ref_count == 0)
+        qdr_check_addr_CT(core, addr);
+}
+
+
+static qd_composed_field_t *qcm_mobile_sync_message_headers(const char *address, const char *opcode)
+{
+    qd_composed_field_t *field = qd_compose(QD_PERFORMATIVE_HEADER, 0);
+    qd_compose_start_list(field);
+    qd_compose_insert_bool(field, 0); // durable
+    qd_compose_end_list(field);
+
+    field = qd_compose(QD_PERFORMATIVE_PROPERTIES, field);
+    qd_compose_start_list(field);
+    qd_compose_insert_null(field);            // message-id
+    qd_compose_insert_null(field);            // user-id
+    qd_compose_insert_string(field, address); // to
+    qd_compose_end_list(field);
+
+    field = qd_compose(QD_PERFORMATIVE_APPLICATION_PROPERTIES, field);
+    qd_compose_start_map(field);
+    qd_compose_insert_symbol(field, OPCODE);
+    qd_compose_insert_string(field, opcode);
+    qd_compose_end_map(field);
+
+    return field;
+}
+
+
+static void qcm_mobile_sync_compose_diff_addr_list(qdrm_mobile_sync_t *msync, qd_composed_field_t *field, bool is_added)
+{
+    qdr_address_list_t *list = is_added ? &msync->added_addrs : &msync->deleted_addrs;
+
+    qd_compose_start_list(field);
+    qdr_address_t *addr = DEQ_HEAD(*list);
+    while (addr) {
+        const char *hash_key = (const char*) qd_hash_key_by_handle(addr->hash_handle);
+        qd_compose_insert_string(field, hash_key);
+        if (is_added) {
+            DEQ_REMOVE_HEAD_N(SYNC_ADD, *list);
+            BIT_CLEAR(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST);
+        } else {
+            DEQ_REMOVE_HEAD_N(SYNC_DEL, *list);
+            BIT_CLEAR(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST);
+            qcm_mobile_sync_stop_tracking(msync->core, addr);
+        }
+        addr = DEQ_HEAD(*list);
+    }
+    qd_compose_end_list(field);
+}
+
+
+static void qcm_mobile_sync_compose_diff_hint_list(qdrm_mobile_sync_t *msync, qd_composed_field_t *field)
+{
+    qd_compose_start_list(field);
+    qdr_address_t *addr = DEQ_HEAD(msync->added_addrs);
+    while (addr) {
+        qd_compose_insert_int(field, addr->treatment);
+        addr = DEQ_NEXT_N(SYNC_ADD, addr);
+    }
+    qd_compose_end_list(field);
+}
+
+
+static qd_message_t *qcm_mobile_sync_compose_differential_mau(qdrm_mobile_sync_t *msync, const char *address)
+{
+    qd_message_t        *msg     = qd_message();
+    qd_composed_field_t *headers = qcm_mobile_sync_message_headers(address, MAU);
+    qd_composed_field_t *body    = qd_compose(QD_PERFORMATIVE_BODY_AMQP_VALUE, 0);
+
+    //
+    // Add the ingress and trace annotations to the message to prevent this multicast from bouncing
+    // back to us.
+    //
+    qd_composed_field_t *ingress = qd_compose_subfield(0);
+    qd_compose_insert_string(ingress, qd_router_id(msync->core->qd));
+
+    qd_composed_field_t *trace = qd_compose_subfield(0);
+    qd_compose_start_list(trace);
+    qd_compose_insert_string(trace, qd_router_id(msync->core->qd));
+    qd_compose_end_list(trace);
+
+    qd_message_set_ingress_annotation(msg, ingress);
+    qd_message_set_trace_annotation(msg, trace);
+
+    //
+    // Generate the message body
+    //
+    qd_compose_start_map(body);
+    qd_compose_insert_symbol(body, ID);
+    qd_compose_insert_string(body, msync->core->router_id);
+
+    qd_compose_insert_symbol(body, PV);
+    qd_compose_insert_long(body, PROTOCOL_VERSION);
+
+    qd_compose_insert_symbol(body, AREA);
+    qd_compose_insert_string(body, msync->core->router_area);
+
+    qd_compose_insert_symbol(body, MOBILE_SEQ);
+    qd_compose_insert_long(body, msync->mobile_seq);
+
+    qd_compose_insert_symbol(body, HINTS);
+    qcm_mobile_sync_compose_diff_hint_list(msync, body);
+
+    qd_compose_insert_symbol(body, ADD);
+    qcm_mobile_sync_compose_diff_addr_list(msync, body, true);
+
+    qd_compose_insert_symbol(body, DEL);
+    qcm_mobile_sync_compose_diff_addr_list(msync, body, false);
+
+    qd_compose_end_map(body);
+
+    qd_message_compose_3(msg, headers, body);
+    qd_compose_free(headers);
+    qd_compose_free(body);
+    return msg;
+}
+
+
+static qd_message_t *qcm_mobile_sync_compose_absolute_mau(qdrm_mobile_sync_t *msync, const char *address)
+{
+    qd_message_t        *msg     = qd_message();
+    qd_composed_field_t *headers = qcm_mobile_sync_message_headers(address, MAU);
+    qd_composed_field_t *body    = qd_compose(QD_PERFORMATIVE_BODY_AMQP_VALUE, 0);
+
+    qd_compose_start_map(body);
+    qd_compose_insert_symbol(body, ID);
+    qd_compose_insert_string(body, msync->core->router_id);
+
+    qd_compose_insert_symbol(body, PV);
+    qd_compose_insert_long(body, PROTOCOL_VERSION);
+
+    qd_compose_insert_symbol(body, AREA);
+    qd_compose_insert_string(body, msync->core->router_area);
+
+    qd_compose_insert_symbol(body, MOBILE_SEQ);
+    qd_compose_insert_long(body, msync->mobile_seq);
+
+    qd_compose_insert_symbol(body, EXIST);
+    qd_compose_start_list(body);
+    qdr_address_t *addr = DEQ_HEAD(msync->core->addrs);
+    while (!!addr) {
+        //
+        // For an address to be included in the list, it must:
+        //   - be a mobile address
+        //   - have at least one local consumer, link-route destination, or exchange
+        //     _OR_ be in the delete list (because the peers haven't heard of its pending deletion)
+        //   - not be in the add list (because the peers haven't heard of its pending addition)
+        //
+        // Note that in the two add/del list cases, we are reporting information that is not currently
+        // accurate.  In these cases, a differentiao MAU will be sent very shortly that will put the
+        // peer router in the correct state.
+        //
+        if (qcm_mobile_sync_addr_is_mobile(addr)
+            && ((DEQ_SIZE(addr->rlinks) > 0 || DEQ_SIZE(addr->conns) > 0 || !!addr->exchange)
+                || BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST))
+            && !BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST)) {
+            const char *hash_key = (const char*) qd_hash_key_by_handle(addr->hash_handle);
+            qd_compose_insert_string(body, hash_key);
+        }
+        addr = DEQ_NEXT(addr);
+    }
+    qd_compose_end_list(body);
+
+    qd_compose_insert_symbol(body, HINTS);
+    qd_compose_start_list(body);
+    addr = DEQ_HEAD(msync->core->addrs);
+    while (!!addr) {
+        //
+        // This loop uses the same logic as above.
+        //
+        if (qcm_mobile_sync_addr_is_mobile(addr)
+            && ((DEQ_SIZE(addr->rlinks) > 0 || DEQ_SIZE(addr->conns) > 0 || !!addr->exchange)
+                || BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST))
+            && !BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST))
+            qd_compose_insert_int(body, addr->treatment);
+        addr = DEQ_NEXT(addr);
+    }
+    qd_compose_end_list(body);
+    qd_compose_end_map(body);
+    qd_message_compose_3(msg, headers, body);
+    qd_compose_free(headers);
+    qd_compose_free(body);
+    return msg;
+}
+
+
+static qd_message_t *qcm_mobile_sync_compose_mar(qdrm_mobile_sync_t *msync, qdr_node_t *router)
+{
+    qd_message_t        *msg     = qd_message();
+    qd_composed_field_t *headers = qcm_mobile_sync_message_headers(router->wire_address_ma, MAR);
+    qd_composed_field_t *body    = qd_compose(QD_PERFORMATIVE_BODY_AMQP_VALUE, 0);
+
+    qd_compose_start_map(body);
+    qd_compose_insert_symbol(body, ID);
+    qd_compose_insert_string(body, msync->core->router_id);
+
+    qd_compose_insert_symbol(body, PV);
+    qd_compose_insert_long(body, PROTOCOL_VERSION);
+
+    qd_compose_insert_symbol(body, AREA);
+    qd_compose_insert_string(body, msync->core->router_area);
+
+    qd_compose_insert_symbol(body, HAVE_SEQ);
+    qd_compose_insert_long(body, router->mobile_seq);
+
+    qd_compose_end_map(body);
+
+    qd_message_compose_3(msg, headers, body);
+    qd_compose_free(headers);
+    qd_compose_free(body);
+    return msg;
+}
+
+
+//================================================================================
+// Timer Handler
+//================================================================================
+
+static void qcm_mobile_sync_on_timer_CT(qdr_core_t *core, void *context)
+{
+    qdrm_mobile_sync_t *msync = (qdrm_mobile_sync_t*) context;
+
+    //
+    // Re-schedule the timer for the next go-around
+    //
+    qdr_core_timer_schedule_CT(core, msync->timer, 0);
+
+    //
+    // Check the add and delete lists.  If they are empty, nothing of note occured in the last
+    // interval.  Exit the handler function.
+    //
+    size_t added_count   = DEQ_SIZE(msync->added_addrs);
+    size_t deleted_count = DEQ_SIZE(msync->deleted_addrs);
+
+    if (added_count == 0 && deleted_count == 0)
+        return;
+
+    //
+    // Bump the mobile sequence number.
+    //
+    msync->mobile_seq++;
+
+    //
+    // Prepare a differential MAU for sending to all the other routers.
+    //
+    qd_message_t *mau = qcm_mobile_sync_compose_differential_mau(msync, "_topo/0/all/qdrouter.ma");
+
+    //
+    // Multicast the control message.  Set the exclude_inprocess and control flags.
+    // Use the TOPOLOGICAL class address for sending.
+    //
+    int fanout = qdr_forward_message_CT(core, core->routerma_addr_T, mau, 0, true, true);
+    qd_message_free(mau);
+
+    //
+    // Post the updated mobile sequence number to the Python router.  It is important that this be
+    // done _after_ sending the differential MAU to prevent a storm of un-needed MAR requests from
+    // the other routers.
+    //
+    qdr_post_set_my_mobile_seq_CT(core, msync->mobile_seq);
+
+    //
+    // Trace log the activity of this sequence update.
+    //
+    qd_log(msync->log, QD_LOG_DEBUG, "New mobile sequence: mobile_seq=%"PRIu64", addrs_added=%ld, addrs_deleted=%ld, fanout=%d",
+           msync->mobile_seq, added_count, deleted_count, fanout);
+}
+
+
+//================================================================================
+// Message Handler
+//================================================================================
+
+static void qcm_mobile_sync_on_mar_CT(qdrm_mobile_sync_t *msync, qd_parsed_field_t *body)
+{
+    if (!!body && qd_parse_is_map(body)) {
+        qd_parsed_field_t *id_field       = qd_parse_value_by_key(body, ID);
+        qd_parsed_field_t *have_seq_field = qd_parse_value_by_key(body, HAVE_SEQ);
+        uint64_t           have_seq       = qd_parse_as_ulong(have_seq_field);
+
+        qdr_node_t *router = qdc_mobile_sync_router_by_id(msync, id_field);
+        if (!!router) {
+            qd_log(msync->log, QD_LOG_DEBUG, "Received MAR from %s, have_seq=%"PRIu64,
+                   (const char*) qd_hash_key_by_handle(router->owning_addr->hash_handle) + 1, have_seq);
+
+            if (have_seq < msync->mobile_seq) {
+                //
+                // The requestor's view of our mobile_seq is less than our actual mobile_sync.
+                // Send them an absolute MAU to get them caught up to the present.
+                //
+                qd_message_t *mau = qcm_mobile_sync_compose_absolute_mau(msync, router->wire_address_ma);
+                (void) qdr_forward_message_CT(msync->core, router->owning_addr, mau, 0, true, true);
+                qd_message_free(mau);
+
+                //
+                // Trace log the activity of this sequence update.
+                //
+                qd_log(msync->log, QD_LOG_DEBUG, "Sent MAU to requestor: mobile_seq=%"PRIu64, msync->mobile_seq);
+            }
+        } else
+            qd_log(msync->log, QD_LOG_ERROR, "Received MAR from an unknown router");
+    }
+}
+
+
+static void qcm_mobile_sync_on_mau_CT(qdrm_mobile_sync_t *msync, qd_parsed_field_t *body)
+{
+    if (!!body && qd_parse_is_map(body)) {
+        qd_parsed_field_t *id_field         = qd_parse_value_by_key(body, ID);
+        qd_parsed_field_t *mobile_seq_field = qd_parse_value_by_key(body, MOBILE_SEQ);
+        uint64_t           mobile_seq       = qd_parse_as_ulong(mobile_seq_field);
+
+        qdr_node_t *router = qdc_mobile_sync_router_by_id(msync, id_field);
+        if (!!router) {
+            const char        *router_id   = (const char*) qd_hash_key_by_handle(router->owning_addr->hash_handle) + 1;
+            qd_parsed_field_t *add_field   = qd_parse_value_by_key(body, ADD);
+            qd_parsed_field_t *del_field   = qd_parse_value_by_key(body, DEL);
+            qd_parsed_field_t *exist_field = qd_parse_value_by_key(body, EXIST);
+            qd_parsed_field_t *hints_field = qd_parse_value_by_key(body, HINTS);
+            uint32_t           hints_count = 0;
+            qdr_address_t     *addr;
+
+            //
+            // Validate the fields and determine what kind of MAU we've received.
+            //
+            if (!!hints_field && qd_parse_is_list(hints_field))
+                hints_count = qd_parse_sub_count(hints_field);
+
+            //
+            // Validate the exist, add, and del fields.  They must, if they exist, be lists.
+            // If there is an exist field, there must not be an add or del field.
+            // If there is no exist field, there must be both an add and a del field.
+            //
+            if ((!!exist_field && !qd_parse_is_list(exist_field))
+                || (!!add_field && !qd_parse_is_list(add_field))
+                || (!!del_field && !qd_parse_is_list(del_field))
+                || (!!exist_field && (!!add_field || !!del_field))
+                || (!exist_field && (!add_field || !del_field))) {
+                qd_log(msync->log, QD_LOG_ERROR, "Received malformed MAU from %s", router_id);
+                return;
+            }
+
+            //
+            // Record the new mobile sequence for the remote router.
+            //
+            router->mobile_seq = mobile_seq;
+
+            //
+            // Check the exist/add list size against the hints-list size.  If they are not
+            // exactly equal, ignore the hints.
+            //
+            if (!!exist_field) {
+                if (hints_count != qd_parse_sub_count(exist_field))
+                    hints_count = 0;
+            } else {
+                if (hints_count != qd_parse_sub_count(add_field))
+                    hints_count = 0;
+            }
+
+            qd_log(msync->log, QD_LOG_DEBUG, "Received MAU (%s) from %s, mobile_seq=%"PRIu64,
+                   !!exist_field ? "absolute" : "differential", router_id, mobile_seq);
+
+            //
+            // If this is an absolute MAU, the existing set of addresses for this router must
+            // be marked as needing deletion, in case they are not mentioned in the existing
+            // address list.
+            //
+            if (!!exist_field) {
+                addr = DEQ_HEAD(msync->core->addrs);
+                while (!!addr) {
+                    if (qcm_mobile_sync_addr_is_mobile(addr) && !!qd_bitmask_value(addr->rnodes, router->mask_bit))
+                        BIT_SET(addr->sync_mask, ADDR_SYNC_TO_BE_DELETED);
+                    addr = DEQ_NEXT(addr);
+                }
+            }
+
+            //
+            // Run through the add/exist list (depending on which we have) and lookup/add the
+            // addresses, associating them with the sending router.  Clear the to-delete bits
+            // on every address touched.  If hints are available, use them for addresses that
+            // are newly created.
+            //
+            qd_parsed_field_t *field      = !!exist_field ? exist_field : add_field;
+            qd_parsed_field_t *addr_field = qd_field_first_child(field);
+            qd_parsed_field_t *hint_field = !!hints_count ? qd_field_first_child(hints_field) : 0;
+            while (addr_field) {
+                qd_iterator_t *iter = qd_parse_raw(addr_field);
+                qdr_address_t *addr = 0;
+                int treatment_hint = !!hint_field ? qd_parse_as_int(hint_field) : -1;
+
+                do {
+                    qd_hash_retrieve(msync->core->addr_hash, iter, (void**) &addr);
+                    if (!addr) {
+                        qdr_address_config_t   *addr_config;
+                        qd_address_treatment_t  treatment =
+                            qdr_treatment_for_address_hash_with_default_CT(msync->core,
+                                                                           iter,
+                                                                           qcm_mobile_sync_default_treatment(msync->core, treatment_hint),
+                                                                           &addr_config);
+                        addr = qdr_address_CT(msync->core, treatment, addr_config);
+                        if (!addr) {
+                            qd_log(msync->log, QD_LOG_CRITICAL, "map_destination: ignored");
+                            assert(false);
+                            break;
+                        }
+                        qd_hash_insert(msync->core->addr_hash, iter, addr, &addr->hash_handle);
+                        DEQ_ITEM_INIT(addr);
+                        DEQ_INSERT_TAIL(msync->core->addrs, addr);
+
+                        //
+                        // if the address is a link route, add the pattern to the wildcard
+                        // address parse tree
+                        //
+                        const char *a_str = (const char*) qd_hash_key_by_handle(addr->hash_handle);
+                        if (QDR_IS_LINK_ROUTE(a_str[0])) {
+                            qdr_link_route_map_pattern_CT(msync->core, iter, addr);
+                        }
+                    }
+
+                    BIT_CLEAR(addr->sync_mask, ADDR_SYNC_TO_BE_DELETED);
+                    if (!qd_bitmask_value(addr->rnodes, router->mask_bit)) {
+                        qd_bitmask_set_bit(addr->rnodes, router->mask_bit);
+                        router->ref_count++;
+                        addr->cost_epoch--;
+                        qdr_addr_start_inlinks_CT(msync->core, addr);
+       
+                        //
+                        // Raise an address event if this is the first destination for the address
+                        //
+                        if (qd_bitmask_cardinality(addr->rnodes) + DEQ_SIZE(addr->rlinks) == 1)
+                            qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_BECAME_DEST, addr);
+                        else if (qd_bitmask_cardinality(addr->rnodes) == 1 && DEQ_SIZE(addr->rlinks) == 1)
+                            qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_TWO_DEST, addr);
+                    }
+                } while (false);
+
+                addr_field = qd_field_next_child(addr_field);
+                hint_field = !!hint_field ? qd_field_next_child(hint_field) : 0;
+            }
+
+            //
+            // Run through the delete list, if it exists, and disassociate each address from the
+            // sending router.  Check the address to see if it needs to be deleted.
+            //
+            if (!!del_field) {
+                addr_field = qd_field_first_child(del_field);
+                while (!!addr_field) {
+                    qd_iterator_t *iter = qd_parse_raw(addr_field);
+                    qdr_address_t *addr = 0;
+
+                    qd_hash_retrieve(msync->core->addr_hash, iter, (void**) &addr);
+                    if (!!addr) {
+                        if (qd_bitmask_value(addr->rnodes, router->mask_bit)) {
+                            qd_bitmask_clear_bit(addr->rnodes, router->mask_bit);
+                            router->ref_count--;
+                            addr->cost_epoch--;
+
+                            //
+                            // Raise an address event if this was the last destination for the address
+                            //
+                            if (qd_bitmask_cardinality(addr->rnodes) + DEQ_SIZE(addr->rlinks) == 0)
+                                qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_NO_LONGER_DEST, addr);
+                            else if (qd_bitmask_cardinality(addr->rnodes) == 0 && DEQ_SIZE(addr->rlinks) == 1)
+                                qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_ONE_LOCAL_DEST, addr);
+
+                            qdr_check_addr_CT(msync->core, addr);
+                        }
+                    }
+                    addr_field = qd_field_next_child(addr_field);
+                }
+            }
+
+            //
+            // If this was an absolute MAU, disassociate any addresses remaining with the
+            // to-delete flag set.
+            //
+            if (!!exist_field) {
+                addr = DEQ_HEAD(msync->core->addrs);
+                while (!!addr) {
+                    qdr_address_t *next_addr = DEQ_NEXT(addr);
+                    if (qcm_mobile_sync_addr_is_mobile(addr)
+                        && !!qd_bitmask_value(addr->rnodes, router->mask_bit)
+                        && BIT_IS_SET(addr->sync_mask, ADDR_SYNC_TO_BE_DELETED)) {
+                        qd_bitmask_clear_bit(addr->rnodes, router->mask_bit);
+                        router->ref_count--;
+                        addr->cost_epoch--;
+
+                        //
+                        // Raise an address event if this was the last destination for the address
+                        //
+                        if (qd_bitmask_cardinality(addr->rnodes) + DEQ_SIZE(addr->rlinks) == 0)
+                            qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_NO_LONGER_DEST, addr);
+                        else if (qd_bitmask_cardinality(addr->rnodes) == 0 && DEQ_SIZE(addr->rlinks) == 1)
+                            qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_ONE_LOCAL_DEST, addr);
+
+                        qdr_check_addr_CT(msync->core, addr);
+                    }
+                    addr = next_addr;
+                }
+            }
+
+            //
+            // Tell the python router about the new mobile sequence
+            //
+            qdr_post_set_mobile_seq_CT(msync->core, router->mask_bit, mobile_seq);
+        } else
+            qd_log(msync->log, QD_LOG_ERROR, "Received MAU from an unknown router");
+    }
+}
+
+
+static void qcm_mobile_sync_on_message_CT(void         *context,
+                                          qd_message_t *msg,
+                                          int           unused_link_maskbit,
+                                          int           unused_inter_router_cost,
+                                          uint64_t      unused_conn_id)
+{
+    qdrm_mobile_sync_t *msync      = (qdrm_mobile_sync_t*) context;
+    qd_iterator_t      *ap_iter    = qd_message_field_iterator(msg, QD_FIELD_APPLICATION_PROPERTIES);
+    qd_iterator_t      *body_iter  = qd_message_field_iterator(msg, QD_FIELD_BODY);
+    qd_parsed_field_t  *ap_field   = qd_parse(ap_iter);
+    qd_parsed_field_t  *body_field = qd_parse(body_iter);
+
+    if (!!ap_field && qd_parse_is_map(ap_field)) {
+        qd_parsed_field_t *opcode_field = qd_parse_value_by_key(ap_field, OPCODE);
+
+        if (qd_iterator_equal(qd_parse_raw(opcode_field), (const unsigned char*) MAR))
+            qcm_mobile_sync_on_mar_CT(msync, body_field);
+
+        if (qd_iterator_equal(qd_parse_raw(opcode_field), (const unsigned char*) MAU))
+            qcm_mobile_sync_on_mau_CT(msync, body_field);
+    }
+
+    qd_parse_free(ap_field);
+    qd_iterator_free(ap_iter);
+    qd_parse_free(body_field);
+    qd_iterator_free(body_iter);
+}
+
+
+//================================================================================
+// Event Handlers
+//================================================================================
+
+static void qcm_mobile_sync_on_became_local_dest_CT(qdrm_mobile_sync_t *msync, qdr_address_t *addr)
+{
+    if (!qcm_mobile_sync_addr_is_mobile(addr))
+        return;
+
+    qd_log(msync->log, QD_LOG_DEBUG, "Became Local Dest: %s", (const char*) qd_hash_key_by_handle(addr->hash_handle));
+
+    if (BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST))
+        return;
+
+    if (BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST)) {
+        //
+        // If the address was deleted since the last update, simply forget that it was deleted.
+        //
+        DEQ_REMOVE_N(SYNC_DEL, msync->deleted_addrs, addr);
+        BIT_CLEAR(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST);
+    } else {
+        DEQ_INSERT_TAIL_N(SYNC_ADD, msync->added_addrs, addr);
+        BIT_SET(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST);
+        qcm_mobile_sync_start_tracking(addr);
+    }
+}
+
+
+static void qcm_mobile_sync_on_no_longer_local_dest_CT(qdrm_mobile_sync_t *msync, qdr_address_t *addr)
+{
+    if (!qcm_mobile_sync_addr_is_mobile(addr))
+        return;
+
+    qd_log(msync->log, QD_LOG_DEBUG, "No Longer Local Dest: %s", (const char*) qd_hash_key_by_handle(addr->hash_handle));
+
+    if (BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST))
+        return;
+
+    if (BIT_IS_SET(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST)) {
+        //
+        // If the address was added since the last update, simply forget that it was added.
+        //
+        DEQ_REMOVE_N(SYNC_ADD, msync->added_addrs, addr);
+        BIT_CLEAR(addr->sync_mask, ADDR_SYNC_IN_ADD_LIST);
+        qcm_mobile_sync_stop_tracking(msync->core, addr);
+    } else {
+        DEQ_INSERT_TAIL_N(SYNC_DEL, msync->deleted_addrs, addr);
+        BIT_SET(addr->sync_mask, ADDR_SYNC_IN_DEL_LIST);
+    }
+}
+
+
+static void qcm_mobile_sync_on_router_flush_CT(qdrm_mobile_sync_t *msync, qdr_node_t *router)
+{
+    router->mobile_seq = 0;
+    qdr_address_t *addr = DEQ_HEAD(msync->core->addrs);
+    while (!!addr) {
+        qdr_address_t *next_addr = DEQ_NEXT(addr);
+        if (qcm_mobile_sync_addr_is_mobile(addr)
+            && !!qd_bitmask_value(addr->rnodes, router->mask_bit)) {
+            //
+            // This is an address mapped to the router.  Unmap the address and clean up.
+            //
+            qd_bitmask_clear_bit(addr->rnodes, router->mask_bit);
+            router->ref_count--;
+            addr->cost_epoch--;
+
+            //
+            // Raise an address event if this was the last destination for the address
+            //
+            if (qd_bitmask_cardinality(addr->rnodes) + DEQ_SIZE(addr->rlinks) == 0)
+                qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_NO_LONGER_DEST, addr);
+            else if (qd_bitmask_cardinality(addr->rnodes) == 0 && DEQ_SIZE(addr->rlinks) == 1)
+                qdrc_event_addr_raise(msync->core, QDRC_EVENT_ADDR_ONE_LOCAL_DEST, addr);
+
+            qdr_check_addr_CT(msync->core, addr);
+        }
+        addr = next_addr;
+    }
+}
+
+
+static void qcm_mobile_sync_on_router_advanced_CT(qdrm_mobile_sync_t *msync, qdr_node_t *router)
+{
+    //
+    // Prepare a MAR to be sent to the router
+    //
+    qd_message_t *mar = qcm_mobile_sync_compose_mar(msync, router);
+
+    //
+    // Send the control message.  Set the exclude_inprocess and control flags.
+    //
+    int fanout = qdr_forward_message_CT(msync->core, router->owning_addr, mar, 0, true, true);
+    qd_message_free(mar);
+
+    //
+    // Trace log the activity of this sequence update.
+    //
+    qd_log(msync->log, QD_LOG_DEBUG, "Send MAR request to router %s, have_seq=%"PRIu64", fanout=%d",
+           (const char*) qd_hash_key_by_handle(router->owning_addr->hash_handle) + 1, router->mobile_seq, fanout);
+}
+
+
+static void qcm_mobile_sync_on_addr_event_CT(void          *context,
+                                             qdrc_event_t   event_type,
+                                             qdr_address_t *addr)
+{
+    qdrm_mobile_sync_t *msync = (qdrm_mobile_sync_t*) context;
+
+    switch (event_type) {
+    case QDRC_EVENT_ADDR_BECAME_LOCAL_DEST:
+        qcm_mobile_sync_on_became_local_dest_CT(msync, addr);
+        break;
+        
+    case QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST:
+        qcm_mobile_sync_on_no_longer_local_dest_CT(msync, addr);
+        break;
+        
+    default:
+        break;
+    }
+}
+
+
+static void qcm_mobile_sync_on_router_event_CT(void          *context,
+                                               qdrc_event_t   event_type,
+                                               qdr_node_t    *router)
+{
+    qdrm_mobile_sync_t *msync = (qdrm_mobile_sync_t*) context;
+
+    switch (event_type) {
+    case QDRC_EVENT_ROUTER_MOBILE_FLUSH:
+        qcm_mobile_sync_on_router_flush_CT(msync, router);
+        break;
+
+    case QDRC_EVENT_ROUTER_MOBILE_SEQ_ADVANCED:
+        qcm_mobile_sync_on_router_advanced_CT(msync, router);
+        break;
+
+    default:
+        break;
+    }
+}
+
+
+//================================================================================
+// Module Handlers
+//================================================================================
+
+static bool qcm_mobile_sync_enable_CT(qdr_core_t *core)
+{
+    return core->router_mode == QD_ROUTER_MODE_INTERIOR;
+}
+
+
+static void qcm_mobile_sync_init_CT(qdr_core_t *core, void **module_context)
+{
+    qdrm_mobile_sync_t *msync = NEW(qdrm_mobile_sync_t);
+    ZERO(msync);
+    msync->core      = core;
+
+    //
+    // Subscribe to core events:
+    //
+    //  - ADDR_BECAME_LOCAL_DEST     - Indicates a new address needs to tbe sync'ed with other routers
+    //  - ADDR_NO_LONGER_LOCAL_DEST  - Indicates an address needs to be un-sync'd with other routers
+    //  - ROUTER_MOBILE_FLUSH        - All addresses associated with the router must be unmapped
+    //  - ROUTER_MOBILE_SEQ_ADVANCED - A router has an advanced mobile-seq and needs to be queried
+    //
+    msync->event_sub = qdrc_event_subscribe_CT(core,
+                                               QDRC_EVENT_ADDR_BECAME_LOCAL_DEST
+                                               | QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST
+                                               | QDRC_EVENT_ROUTER_MOBILE_FLUSH
+                                               | QDRC_EVENT_ROUTER_MOBILE_SEQ_ADVANCED,
+                                               0,
+                                               0,
+                                               qcm_mobile_sync_on_addr_event_CT,
+                                               qcm_mobile_sync_on_router_event_CT,
+                                               msync);
+
+    //
+    // Create and schedule a one-second recurring timer to drive the sync protocol
+    //
+    msync->timer = qdr_core_timer_CT(core, qcm_mobile_sync_on_timer_CT, msync);
+    qdr_core_timer_schedule_CT(core, msync->timer, 0);
+
+    //
+    // Subscribe to receive messages sent to the 'qdrouter.ma' addresses
+    //
+    msync->message_sub1 = qdr_core_subscribe(core, "qdrouter.ma", 'L', '0',
+                                             QD_TREATMENT_MULTICAST_ONCE, true, qcm_mobile_sync_on_message_CT, msync);
+    msync->message_sub2 = qdr_core_subscribe(core, "qdrouter.ma", 'T', '0',
+                                             QD_TREATMENT_MULTICAST_ONCE, true, qcm_mobile_sync_on_message_CT, msync);
+
+    //
+    // Create a log source for mobile address sync
+    //
+    msync->log = qd_log_source("ROUTER_MA");
+
+    *module_context = msync;
+}
+
+
+static void qcm_mobile_sync_final_CT(void *module_context)
+{
+    qdrm_mobile_sync_t *msync = (qdrm_mobile_sync_t*) module_context;
+
+    qdrc_event_unsubscribe_CT(msync->core, msync->event_sub);
+    qdr_core_timer_free_CT(msync->core, msync->timer);
+
+    //
+    // Don't explicitly unsubscribe the addresses, these are already gone at module-final time.
+    //
+
+    free(msync);
+}
+
+
+QDR_CORE_MODULE_DECLARE("mobile_sync", qcm_mobile_sync_enable_CT, qcm_mobile_sync_init_CT, qcm_mobile_sync_final_CT)
diff --git a/src/router_core/modules/test_hooks/core_test_hooks.c b/src/router_core/modules/test_hooks/core_test_hooks.c
index 86f4095..263b9d9 100644
--- a/src/router_core/modules/test_hooks/core_test_hooks.c
+++ b/src/router_core/modules/test_hooks/core_test_hooks.c
@@ -649,7 +649,7 @@
     tc->conn_events = qdrc_event_subscribe_CT(test_module->core,
                                               (QDRC_EVENT_CONN_OPENED | QDRC_EVENT_CONN_CLOSED),
                                               _on_conn_event,
-                                              NULL, NULL, tc);
+                                              0, 0, 0, tc);
 
     qd_log(test_module->core->log, QD_LOG_TRACE, "client test registered %p", tc->conn_events);
 }
diff --git a/src/router_core/route_tables.c b/src/router_core/route_tables.c
index 3466732..d6fdb15 100644
--- a/src/router_core/route_tables.c
+++ b/src/router_core/route_tables.c
@@ -21,18 +21,18 @@
 #include "route_control.h"
 #include <stdio.h>
 
-static void qdr_add_router_CT        (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_del_router_CT        (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_set_link_CT          (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_remove_link_CT       (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_set_next_hop_CT      (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_remove_next_hop_CT   (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_set_cost_CT          (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_set_valid_origins_CT (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_map_destination_CT   (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_unmap_destination_CT (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_subscribe_CT         (qdr_core_t *core, qdr_action_t *action, bool discard);
-static void qdr_unsubscribe_CT       (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_add_router_CT          (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_del_router_CT          (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_set_link_CT            (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_remove_link_CT         (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_set_next_hop_CT        (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_remove_next_hop_CT     (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_set_cost_CT            (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_set_valid_origins_CT   (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_flush_destinations_CT  (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_mobile_seq_advanced_CT (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_subscribe_CT           (qdr_core_t *core, qdr_action_t *action, bool discard);
+static void qdr_unsubscribe_CT         (qdr_core_t *core, qdr_action_t *action, bool discard);
 
 
 //==================================================================================
@@ -108,34 +108,32 @@
 }
 
 
-void qdr_core_map_destination(qdr_core_t *core, int router_maskbit, const char *address_hash, int treatment_hint)
+void qdr_core_flush_destinations(qdr_core_t *core, int router_maskbit)
 {
-    qdr_action_t *action = qdr_action(qdr_map_destination_CT, "map_destination");
+    qdr_action_t *action = qdr_action(qdr_flush_destinations_CT, "flush_destinations");
     action->args.route_table.router_maskbit = router_maskbit;
-    action->args.route_table.address        = qdr_field(address_hash);
-    action->args.route_table.treatment_hint = treatment_hint;
     qdr_action_enqueue(core, action);
 }
 
 
-void qdr_core_unmap_destination(qdr_core_t *core, int router_maskbit, const char *address_hash)
+void qdr_core_mobile_seq_advanced(qdr_core_t *core, int router_maskbit)
 {
-    qdr_action_t *action = qdr_action(qdr_unmap_destination_CT, "unmap_destination");
+    qdr_action_t *action = qdr_action(qdr_mobile_seq_advanced_CT, "mobile_seq_advanced");
     action->args.route_table.router_maskbit = router_maskbit;
-    action->args.route_table.address        = qdr_field(address_hash);
     qdr_action_enqueue(core, action);
 }
 
-void qdr_core_route_table_handlers(qdr_core_t           *core, 
-                                   void                 *context,
-                                   qdr_mobile_added_t    mobile_added,
-                                   qdr_mobile_removed_t  mobile_removed,
-                                   qdr_link_lost_t       link_lost)
+
+void qdr_core_route_table_handlers(qdr_core_t              *core, 
+                                   void                    *context,
+                                   qdr_set_mobile_seq_t     set_mobile_seq,
+                                   qdr_set_my_mobile_seq_t  set_my_mobile_seq,
+                                   qdr_link_lost_t          link_lost)
 {
-    core->rt_context        = context;
-    core->rt_mobile_added   = mobile_added;
-    core->rt_mobile_removed = mobile_removed;
-    core->rt_link_lost      = link_lost;
+    core->rt_context           = context;
+    core->rt_set_mobile_seq    = set_mobile_seq;
+    core->rt_set_my_mobile_seq = set_my_mobile_seq;
+    core->rt_link_lost         = link_lost;
 }
 
 
@@ -144,6 +142,7 @@
                                        char                    aclass,
                                        char                    phase,
                                        qd_address_treatment_t  treatment,
+                                       bool                    in_core,
                                        qdr_receive_t           on_message,
                                        void                   *context)
 {
@@ -152,6 +151,7 @@
     sub->addr               = 0;
     sub->on_message         = on_message;
     sub->on_message_context = context;
+    sub->in_core            = in_core;
 
     qdr_action_t *action = qdr_action(qdr_subscribe_CT, "subscribe");
     action->args.io.address       = qdr_field(address);
@@ -298,23 +298,26 @@
         }
 
         //
-        // Set the block-deletion flag on this address for the time that it is associated
-        // with an existing remote router node.
+        // Bump the address's ref_count for the time that it is associated with an existing remote router node.
         //
-        addr->block_deletion = true;
+        addr->ref_count++;
 
         //
         // Create a router-node record to represent the remote router.
         //
         qdr_node_t *rnode = new_qdr_node_t();
-        DEQ_ITEM_INIT(rnode);
+        ZERO(rnode);
         rnode->owning_addr       = addr;
         rnode->mask_bit          = router_maskbit;
-        rnode->next_hop          = 0;
         rnode->link_mask_bit     = -1;
-        rnode->ref_count         = 0;
         rnode->valid_origins     = qd_bitmask(0);
-        rnode->cost              = 0;
+
+        qd_iterator_reset_view(iter, ITER_VIEW_ALL);
+        int addr_len = qd_iterator_length(iter);
+
+        rnode->wire_address_ma = (char*) malloc(addr_len + 4);
+        qd_iterator_ncopy(iter, (unsigned char*) rnode->wire_address_ma, addr_len);
+        strcpy(rnode->wire_address_ma + addr_len, ".ma");
 
         //
         // Insert at the head of the list because we don't yet know the cost to this
@@ -400,7 +403,7 @@
     //
     // Check the address and free it if there are no other interested parties tracking it
     //
-    oaddr->block_deletion = false;
+    oaddr->ref_count--;
     qdr_check_addr_CT(core, oaddr);
 }
 
@@ -558,141 +561,58 @@
         qd_bitmask_free(valid_origins);
 }
 
-static qd_address_treatment_t default_treatment(qdr_core_t *core, int hint) {
-    switch (hint) {
-    case QD_TREATMENT_MULTICAST_FLOOD:
-        return QD_TREATMENT_MULTICAST_FLOOD;
-    case QD_TREATMENT_MULTICAST_ONCE:
-        return QD_TREATMENT_MULTICAST_ONCE;
-    case QD_TREATMENT_ANYCAST_CLOSEST:
-        return QD_TREATMENT_ANYCAST_CLOSEST;
-    case QD_TREATMENT_ANYCAST_BALANCED:
-        return QD_TREATMENT_ANYCAST_BALANCED;
-    case QD_TREATMENT_LINK_BALANCED:
-        return QD_TREATMENT_LINK_BALANCED;
-    case QD_TREATMENT_UNAVAILABLE:
-        return QD_TREATMENT_UNAVAILABLE;
-    default:
-        return core->qd->default_treatment == QD_TREATMENT_UNAVAILABLE ? QD_TREATMENT_ANYCAST_BALANCED : core->qd->default_treatment;
-    }
-}
 
-static void qdr_map_destination_CT(qdr_core_t *core, qdr_action_t *action, bool discard)
+static void qdr_flush_destinations_CT(qdr_core_t *core, qdr_action_t *action, bool discard)
 {
-    int          router_maskbit = action->args.route_table.router_maskbit;
-    qdr_field_t *address        = action->args.route_table.address;
-    int          treatment_hint = action->args.route_table.treatment_hint;
-
-    if (discard) {
-        qdr_field_free(address);
+    if (!!discard)
         return;
-    }
+
+    int router_maskbit = action->args.route_table.router_maskbit;
 
     do {
         if (router_maskbit >= qd_bitmask_width() || router_maskbit < 0) {
-            qd_log(core->log, QD_LOG_CRITICAL, "map_destination: Router maskbit out of range: %d", router_maskbit);
+            qd_log(core->log, QD_LOG_CRITICAL, "flush_destinations: Router maskbit out of range: %d", router_maskbit);
             break;
         }
 
-        if (core->routers_by_mask_bit[router_maskbit] == 0) {
-            qd_log(core->log, QD_LOG_CRITICAL, "map_destination: Router not found");
-            break;
-        }
-
-        qd_iterator_t *iter = address->iterator;
-        qdr_address_t *addr = 0;
-
-        qd_hash_retrieve(core->addr_hash, iter, (void**) &addr);
-        if (!addr) {
-            qdr_address_config_t   *addr_config;
-            qd_address_treatment_t  treatment = qdr_treatment_for_address_hash_with_default_CT(core,
-                                                                                               iter,
-                                                                                               default_treatment(core, treatment_hint),
-                                                                                               &addr_config);
-            addr = qdr_address_CT(core, treatment, addr_config);
-            if (!addr) {
-                qd_log(core->log, QD_LOG_CRITICAL, "map_destination: ignored");
-                break;
-            }
-            qd_hash_insert(core->addr_hash, iter, addr, &addr->hash_handle);
-            DEQ_ITEM_INIT(addr);
-            DEQ_INSERT_TAIL(core->addrs, addr);
-            // if the address is a link route, add the pattern to the wildcard
-            // address parse tree
-            {
-                const char *a_str = (const char *)qd_hash_key_by_handle(addr->hash_handle);
-                if (QDR_IS_LINK_ROUTE(a_str[0])) {
-                    qdr_link_route_map_pattern_CT(core, iter, addr);
-                }
-            }
-        }
-
         qdr_node_t *rnode = core->routers_by_mask_bit[router_maskbit];
-        qd_bitmask_set_bit(addr->rnodes, router_maskbit);
-        rnode->ref_count++;
-        addr->cost_epoch--;
-        qdr_addr_start_inlinks_CT(core, addr);
+        if (rnode == 0) {
+            qd_log(core->log, QD_LOG_CRITICAL, "flush_destinations: Router not found");
+            break;
+        }
 
         //
-        // Raise an address event if this is the first destination for the address
+        // Raise the event to be picked up by core modules.
         //
-        if (qd_bitmask_cardinality(addr->rnodes) + DEQ_SIZE(addr->rlinks) == 1)
-            qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_BECAME_DEST, addr);
-        else if (qd_bitmask_cardinality(addr->rnodes) == 1 && DEQ_SIZE(addr->rlinks) == 1)
-            qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_TWO_DEST, addr);
+        qdrc_event_router_raise(core, QDRC_EVENT_ROUTER_MOBILE_FLUSH, rnode);
     } while (false);
-
-    qdr_field_free(address);
 }
 
 
-static void qdr_unmap_destination_CT(qdr_core_t *core, qdr_action_t *action, bool discard)
+static void qdr_mobile_seq_advanced_CT(qdr_core_t *core, qdr_action_t *action, bool discard)
 {
-    int          router_maskbit = action->args.route_table.router_maskbit;
-    qdr_field_t *address        = action->args.route_table.address;
-
-    if (discard) {
-        qdr_field_free(address);
+    if (!!discard)
         return;
-    }
+
+    int router_maskbit = action->args.route_table.router_maskbit;
 
     do {
         if (router_maskbit >= qd_bitmask_width() || router_maskbit < 0) {
-            qd_log(core->log, QD_LOG_CRITICAL, "unmap_destination: Router maskbit out of range: %d", router_maskbit);
+            qd_log(core->log, QD_LOG_CRITICAL, "seq_advanced: Router maskbit out of range: %d", router_maskbit);
             break;
         }
 
-        if (core->routers_by_mask_bit[router_maskbit] == 0) {
-            qd_log(core->log, QD_LOG_CRITICAL, "unmap_destination: Router not found");
+        qdr_node_t *rnode = core->routers_by_mask_bit[router_maskbit];
+        if (rnode == 0) {
+            qd_log(core->log, QD_LOG_CRITICAL, "seq_advanced: Router not found");
             break;
         }
 
-        qdr_node_t    *rnode = core->routers_by_mask_bit[router_maskbit];
-        qd_iterator_t *iter  = address->iterator;
-        qdr_address_t *addr  = 0;
-
-        qd_hash_retrieve(core->addr_hash, iter, (void**) &addr);
-        if (!addr) {
-            qd_log(core->log, QD_LOG_CRITICAL, "unmap_destination: Address not found");
-            break;
-        }
-        
-        qd_bitmask_clear_bit(addr->rnodes, router_maskbit);
-        rnode->ref_count--;
-        addr->cost_epoch--;
-
         //
-        // Raise an address event if this was the last destination for the address
+        // Raise the event to be picked up by core modules.
         //
-        if (qd_bitmask_cardinality(addr->rnodes) + DEQ_SIZE(addr->rlinks) == 0)
-            qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_NO_LONGER_DEST, addr);
-        else if (qd_bitmask_cardinality(addr->rnodes) == 0 && DEQ_SIZE(addr->rlinks) == 1)
-            qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_ONE_LOCAL_DEST, addr);
-
-        qdr_check_addr_CT(core, addr);
+        qdrc_event_router_raise(core, QDRC_EVENT_ROUTER_MOBILE_SEQ_ADVANCED, rnode);
     } while (false);
-
-    qdr_field_free(address);
 }
 
 
@@ -754,27 +674,15 @@
 // Call-back Functions
 //==================================================================================
 
-static void qdr_do_mobile_added(qdr_core_t *core, qdr_general_work_t *work)
+static void qdr_do_set_mobile_seq(qdr_core_t *core, qdr_general_work_t *work)
 {
-    char *address_hash = qdr_field_copy(work->field);
-    if (address_hash) {
-        core->rt_mobile_added(core->rt_context, address_hash, work->treatment);
-        free(address_hash);
-    }
-
-    qdr_field_free(work->field);
+    core->rt_set_mobile_seq(core->rt_context, work->maskbit, work->mobile_seq);
 }
 
 
-static void qdr_do_mobile_removed(qdr_core_t *core, qdr_general_work_t *work)
+static void qdr_do_set_my_mobile_seq(qdr_core_t *core, qdr_general_work_t *work)
 {
-    char *address_hash = qdr_field_copy(work->field);
-    if (address_hash) {
-        core->rt_mobile_removed(core->rt_context, address_hash);
-        free(address_hash);
-    }
-
-    qdr_field_free(work->field);
+    core->rt_set_my_mobile_seq(core->rt_context, work->mobile_seq);
 }
 
 
@@ -784,19 +692,19 @@
 }
 
 
-void qdr_post_mobile_added_CT(qdr_core_t *core, const char *address_hash, qd_address_treatment_t treatment)
+void qdr_post_set_mobile_seq_CT(qdr_core_t *core, int router_maskbit, uint64_t mobile_seq)
 {
-    qdr_general_work_t *work = qdr_general_work(qdr_do_mobile_added);
-    work->field = qdr_field(address_hash);
-    work->treatment = treatment;
+    qdr_general_work_t *work = qdr_general_work(qdr_do_set_mobile_seq);
+    work->mobile_seq = mobile_seq;
+    work->maskbit    = router_maskbit;
     qdr_post_general_work_CT(core, work);
 }
 
 
-void qdr_post_mobile_removed_CT(qdr_core_t *core, const char *address_hash)
+void qdr_post_set_my_mobile_seq_CT(qdr_core_t *core, uint64_t mobile_seq)
 {
-    qdr_general_work_t *work = qdr_general_work(qdr_do_mobile_removed);
-    work->field = qdr_field(address_hash);
+    qdr_general_work_t *work = qdr_general_work(qdr_do_set_my_mobile_seq);
+    work->mobile_seq = mobile_seq;
     qdr_post_general_work_CT(core, work);
 }
 
diff --git a/src/router_core/router_core.c b/src/router_core/router_core.c
index 3ecea9c..bdbfb6e 100644
--- a/src/router_core/router_core.c
+++ b/src/router_core/router_core.c
@@ -37,6 +37,7 @@
 ALLOC_DEFINE(qdr_link_work_t);
 ALLOC_DEFINE(qdr_connection_ref_t);
 ALLOC_DEFINE(qdr_connection_info_t);
+ALLOC_DEFINE(qdr_subscription_ref_t);
 
 static void qdr_general_handler(void *context);
 
@@ -86,10 +87,10 @@
     // Perform outside-of-thread setup for the management agent
     //
     core->agent_subscription_mobile = qdr_core_subscribe(core, "$management", 'M', '0',
-                                                         QD_TREATMENT_ANYCAST_CLOSEST,
+                                                         QD_TREATMENT_ANYCAST_CLOSEST, false,
                                                          qdr_management_agent_on_message, core);
     core->agent_subscription_local = qdr_core_subscribe(core, "$management", 'L', '0',
-                                                        QD_TREATMENT_ANYCAST_CLOSEST,
+                                                        QD_TREATMENT_ANYCAST_CLOSEST, false,
                                                         qdr_management_agent_on_message, core);
 
     return core;
@@ -220,6 +221,7 @@
     DEQ_REMOVE(core->routers, rnode);
     core->routers_by_mask_bit[rnode->mask_bit] = 0;
     core->cost_epoch++;
+    free(rnode->wire_address_ma);
     free_qdr_node_t(rnode);
 }
 
@@ -376,7 +378,7 @@
         if (addr) {
             qd_hash_insert(core->addr_hash, iter, addr, &addr->hash_handle);
             DEQ_INSERT_TAIL(core->addrs, addr);
-            addr->block_deletion = true;
+            addr->ref_count++;
             addr->local = (aclass == 'L');
         }
     }
@@ -553,8 +555,6 @@
     if (link->link_direction == QD_OUTGOING) {
         qdr_add_link_ref(&addr->rlinks, link, QDR_LINK_LIST_CLASS_ADDRESS);
         if (DEQ_SIZE(addr->rlinks) == 1) {
-            if (key && (*key == QD_ITER_HASH_PREFIX_EDGE_SUMMARY || *key == QD_ITER_HASH_PREFIX_MOBILE))
-                qdr_post_mobile_added_CT(core, key, addr->treatment);
             qdr_addr_start_inlinks_CT(core, addr);
             qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_BECAME_LOCAL_DEST, addr);
         } else if (DEQ_SIZE(addr->rlinks) == 2 && qd_bitmask_cardinality(addr->rnodes) == 0)
@@ -581,9 +581,6 @@
     if (link->link_direction == QD_OUTGOING) {
         qdr_del_link_ref(&addr->rlinks, link, QDR_LINK_LIST_CLASS_ADDRESS);
         if (DEQ_SIZE(addr->rlinks) == 0) {
-            const char *key = (const char*) qd_hash_key_by_handle(addr->hash_handle);
-            if (key && (*key == QD_ITER_HASH_PREFIX_MOBILE || *key == QD_ITER_HASH_PREFIX_EDGE_SUMMARY))
-                qdr_post_mobile_removed_CT(core, key);
             qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST, addr);
         } else if (DEQ_SIZE(addr->rlinks) == 1 && qd_bitmask_cardinality(addr->rnodes) == 0)
             qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_ONE_LOCAL_DEST, addr);
@@ -608,8 +605,6 @@
 {
     qdr_add_connection_ref(&addr->conns, conn);
     if (DEQ_SIZE(addr->conns) == 1) {
-        const char *key = (const char*) qd_hash_key_by_handle(addr->hash_handle);
-        qdr_post_mobile_added_CT(core, key, addr->treatment);
         qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_BECAME_LOCAL_DEST, addr);
     }
 }
@@ -619,8 +614,6 @@
 {
     qdr_del_connection_ref(&addr->conns, conn);
     if (DEQ_IS_EMPTY(addr->conns)) {
-        const char *key = (const char*) qd_hash_key_by_handle(addr->hash_handle);
-        qdr_post_mobile_removed_CT(core, key);
         qdrc_event_addr_raise(core, QDRC_EVENT_ADDR_NO_LONGER_LOCAL_DEST, addr);
     }
 }
@@ -691,6 +684,7 @@
     qd_iterator_free(pattern);
 }
 
+
 void qdr_add_link_ref(qdr_link_ref_list_t *ref_list, qdr_link_t *link, int cls)
 {
     if (link->ref[cls] != 0)
@@ -763,6 +757,22 @@
 }
 
 
+void qdr_add_subscription_ref_CT(qdr_subscription_ref_list_t *list, qdr_subscription_t *sub)
+{
+    qdr_subscription_ref_t *ref = new_qdr_subscription_ref_t();
+    DEQ_ITEM_INIT(ref);
+    ref->sub = sub;
+    DEQ_INSERT_TAIL(*list, ref);
+}
+
+
+void qdr_del_subscription_ref_CT(qdr_subscription_ref_list_t *list, qdr_subscription_ref_t *ref)
+{
+    DEQ_REMOVE(*list, ref);
+    free_qdr_subscription_ref_t(ref);
+}
+
+
 static void qdr_general_handler(void *context)
 {
     qdr_core_t              *core = (qdr_core_t*) context;
diff --git a/src/router_core/router_core_private.h b/src/router_core/router_core_private.h
index cf6d044..614b8d5 100644
--- a/src/router_core/router_core_private.h
+++ b/src/router_core/router_core_private.h
@@ -231,17 +231,16 @@
 struct qdr_general_work_t {
     DEQ_LINKS(qdr_general_work_t);
     qdr_general_work_handler_t   handler;
-    qdr_field_t                 *field;
     int                          maskbit;
     int                          inter_router_cost;
     qd_message_t                *msg;
     qdr_receive_t                on_message;
     void                        *on_message_context;
     uint64_t                     in_conn_id;
-    int                          treatment;
+    uint64_t                     mobile_seq;
     qdr_delivery_cleanup_list_t  delivery_cleanup_list;
-    qdr_global_stats_handler_t  stats_handler;
-    void                       *context;
+    qdr_global_stats_handler_t   stats_handler;
+    void                        *context;
 };
 
 ALLOC_DECLARE(qdr_general_work_t);
@@ -349,6 +348,8 @@
     uint32_t          ref_count;
     qd_bitmask_t     *valid_origins;
     int               cost;
+    uint64_t          mobile_seq;
+    char             *wire_address_ma;    ///< The address of this router's mobile-sync agent in non-hashed form
 };
 
 DEQ_DECLARE(qdr_node_t, qdr_node_list_t);
@@ -380,10 +381,22 @@
     qdr_address_t *addr;
     qdr_receive_t  on_message;
     void          *on_message_context;
+    bool           in_core;
 };
 
 DEQ_DECLARE(qdr_subscription_t, qdr_subscription_list_t);
 
+typedef struct qdr_subscription_ref_t {
+    DEQ_LINKS(struct qdr_subscription_ref_t);
+    qdr_subscription_t *sub;
+} qdr_subscription_ref_t;
+
+ALLOC_DECLARE(qdr_subscription_ref_t);
+DEQ_DECLARE(qdr_subscription_ref_t, qdr_subscription_ref_list_t);
+
+void qdr_add_subscription_ref_CT(qdr_subscription_ref_list_t *list, qdr_subscription_t *sub);
+void qdr_del_subscription_ref_CT(qdr_subscription_ref_list_t *list, qdr_subscription_ref_t *ref);
+
 DEQ_DECLARE(qdr_delivery_t, qdr_delivery_list_t);
 
 void qdr_add_delivery_ref_CT(qdr_delivery_ref_list_t *list, qdr_delivery_t *dlv);
@@ -508,14 +521,20 @@
     qdr_link_t                *edge_outlink;  ///< [ref] Out-link to connected Interior router (on edge router)
     qd_address_treatment_t     treatment;
     qdr_forwarder_t           *forwarder;
-    int                        ref_count;     ///< Number of link-routes + auto-links referencing this address
-    bool                       block_deletion;
+    int                        ref_count;     ///< Number of entities referencing this address
     bool                       local;
     bool                       router_control_only; ///< If set, address is only for deliveries arriving on a control link
     uint32_t                   tracked_deliveries;
     uint64_t                   cost_epoch;
 
     //
+    // State for mobile-address synchronization
+    //
+    DEQ_LINKS_N(SYNC_ADD, qdr_address_t);
+    DEQ_LINKS_N(SYNC_DEL, qdr_address_t);
+    uint32_t sync_mask;
+
+    //
     // State for tracking fallback destinations for undeliverable deliveries
     //
     qdr_address_t *fallback;     ///< Pointer to this address's fallback destination
@@ -793,10 +812,10 @@
     //
     // Route table section
     //
-    void                 *rt_context;
-    qdr_mobile_added_t    rt_mobile_added;
-    qdr_mobile_removed_t  rt_mobile_removed;
-    qdr_link_lost_t       rt_link_lost;
+    void                    *rt_context;
+    qdr_set_mobile_seq_t     rt_set_mobile_seq;
+    qdr_set_my_mobile_seq_t  rt_set_my_mobile_seq;
+    qdr_link_lost_t          rt_link_lost;
 
     //
     // Connection section
@@ -821,6 +840,7 @@
     qdrc_event_subscription_list_t conn_event_subscriptions;
     qdrc_event_subscription_list_t link_event_subscriptions;
     qdrc_event_subscription_list_t addr_event_subscriptions;
+    qdrc_event_subscription_list_t router_event_subscriptions;
 
     qd_router_mode_t  router_mode;
     const char       *router_area;
@@ -918,8 +938,8 @@
 void qdr_in_process_send_to_CT(qdr_core_t *core, qd_iterator_t *address, qd_message_t *msg, bool exclude_inprocess, bool control);
 void qdr_agent_enqueue_response_CT(qdr_core_t *core, qdr_query_t *query);
 
-void qdr_post_mobile_added_CT(qdr_core_t *core, const char *address_hash, qd_address_treatment_t treatment);
-void qdr_post_mobile_removed_CT(qdr_core_t *core, const char *address_hash);
+void qdr_post_set_mobile_seq_CT(qdr_core_t *core, int router_maskbit, uint64_t mobile_seq);
+void qdr_post_set_my_mobile_seq_CT(qdr_core_t *core, uint64_t mobile_seq);
 void qdr_post_link_lost_CT(qdr_core_t *core, int link_maskbit);
 
 void qdr_post_general_work_CT(qdr_core_t *core, qdr_general_work_t *work);
diff --git a/src/router_pynode.c b/src/router_pynode.c
index 1d0c8d5..200e297 100644
--- a/src/router_pynode.c
+++ b/src/router_pynode.c
@@ -28,12 +28,12 @@
 #include "entity_cache.h"
 #include "python_private.h"
 
-static qd_log_source_t *log_source = 0;
-static PyObject        *pyRouter   = 0;
-static PyObject        *pyTick     = 0;
-static PyObject        *pyAdded    = 0;
-static PyObject        *pyRemoved  = 0;
-static PyObject        *pyLinkLost = 0;
+static qd_log_source_t *log_source       = 0;
+static PyObject        *pyRouter         = 0;
+static PyObject        *pyTick           = 0;
+static PyObject        *pySetMobileSeq   = 0;
+static PyObject        *pySetMyMobileSeq = 0;
+static PyObject        *pyLinkLost       = 0;
 
 typedef struct {
     PyObject_HEAD
@@ -237,15 +237,13 @@
 }
 
 
-static PyObject* qd_map_destination(PyObject *self, PyObject *args)
+static PyObject* qd_flush_destinations(PyObject *self, PyObject *args)
 {
     RouterAdapter *adapter = (RouterAdapter*) self;
     qd_router_t   *router  = adapter->router;
-    const char    *addr_string;
-    int            treatment;
     int            maskbit;
 
-    if (!PyArg_ParseTuple(args, "sii", &addr_string, &treatment, &maskbit))
+    if (!PyArg_ParseTuple(args, "i", &maskbit))
         return 0;
 
     if (maskbit >= qd_bitmask_width() || maskbit < 0) {
@@ -253,21 +251,20 @@
         return 0;
     }
 
-    qdr_core_map_destination(router->router_core, maskbit, addr_string, treatment);
+    qdr_core_flush_destinations(router->router_core, maskbit);
 
     Py_INCREF(Py_None);
     return Py_None;
 }
 
 
-static PyObject* qd_unmap_destination(PyObject *self, PyObject *args)
+static PyObject* qd_mobile_seq_advanced(PyObject *self, PyObject *args)
 {
     RouterAdapter *adapter = (RouterAdapter*) self;
     qd_router_t   *router  = adapter->router;
-    const char    *addr_string;
     int            maskbit;
 
-    if (!PyArg_ParseTuple(args, "si", &addr_string, &maskbit))
+    if (!PyArg_ParseTuple(args, "i", &maskbit))
         return 0;
 
     if (maskbit >= qd_bitmask_width() || maskbit < 0) {
@@ -275,12 +272,13 @@
         return 0;
     }
 
-    qdr_core_unmap_destination(router->router_core, maskbit, addr_string);
+    qdr_core_mobile_seq_advanced(router->router_core, maskbit);
 
     Py_INCREF(Py_None);
     return Py_None;
 }
 
+
 static PyObject* qd_get_agent(PyObject *self, PyObject *args) {
     RouterAdapter *adapter = (RouterAdapter*) self;
     PyObject *agent = adapter->router->qd->agent;
@@ -292,18 +290,18 @@
 }
 
 static PyMethodDef RouterAdapter_methods[] = {
-    {"add_router",          qd_add_router,        METH_VARARGS, "A new remote/reachable router has been discovered"},
-    {"del_router",          qd_del_router,        METH_VARARGS, "We've lost reachability to a remote router"},
-    {"set_link",            qd_set_link,          METH_VARARGS, "Set the link for a neighbor router"},
-    {"remove_link",         qd_remove_link,       METH_VARARGS, "Remove the link for a neighbor router"},
-    {"set_next_hop",        qd_set_next_hop,      METH_VARARGS, "Set the next hop for a remote router"},
-    {"remove_next_hop",     qd_remove_next_hop,   METH_VARARGS, "Remove the next hop for a remote router"},
-    {"set_cost",            qd_set_cost,          METH_VARARGS, "Set the cost to reach a remote router"},
-    {"set_valid_origins",   qd_set_valid_origins, METH_VARARGS, "Set the valid origins for a remote router"},
-    {"set_radius",          qd_set_radius,        METH_VARARGS, "Set the current topology radius"},
-    {"map_destination",     qd_map_destination,   METH_VARARGS, "Add a newly discovered destination mapping"},
-    {"unmap_destination",   qd_unmap_destination, METH_VARARGS, "Delete a destination mapping"},
-    {"get_agent",           qd_get_agent,         METH_VARARGS, "Get the management agent"},
+    {"add_router",          qd_add_router,          METH_VARARGS, "A new remote/reachable router has been discovered"},
+    {"del_router",          qd_del_router,          METH_VARARGS, "We've lost reachability to a remote router"},
+    {"set_link",            qd_set_link,            METH_VARARGS, "Set the link for a neighbor router"},
+    {"remove_link",         qd_remove_link,         METH_VARARGS, "Remove the link for a neighbor router"},
+    {"set_next_hop",        qd_set_next_hop,        METH_VARARGS, "Set the next hop for a remote router"},
+    {"remove_next_hop",     qd_remove_next_hop,     METH_VARARGS, "Remove the next hop for a remote router"},
+    {"set_cost",            qd_set_cost,            METH_VARARGS, "Set the cost to reach a remote router"},
+    {"set_valid_origins",   qd_set_valid_origins,   METH_VARARGS, "Set the valid origins for a remote router"},
+    {"set_radius",          qd_set_radius,          METH_VARARGS, "Set the current topology radius"},
+    {"flush_destinations",  qd_flush_destinations,  METH_VARARGS, "Remove all mapped destinations from a router"},
+    {"mobile_seq_advanced", qd_mobile_seq_advanced, METH_VARARGS, "Mobile sequence for a router moved ahead of the local value"},
+    {"get_agent",           qd_get_agent,           METH_VARARGS, "Get the management agent"},
     {0, 0, 0, 0}
 };
 
@@ -317,18 +315,18 @@
 };
 
 
-static void qd_router_mobile_added(void *context, const char *address_hash, qd_address_treatment_t treatment)
+static void qd_router_set_mobile_seq(void *context, int router_mask_bit, uint64_t mobile_seq)
 {
     qd_router_t *router = (qd_router_t*) context;
     PyObject    *pArgs;
     PyObject    *pValue;
 
-    if (pyAdded && router->router_mode == QD_ROUTER_MODE_INTERIOR) {
+    if (pySetMobileSeq && router->router_mode == QD_ROUTER_MODE_INTERIOR) {
         qd_python_lock_state_t lock_state = qd_python_lock();
         pArgs = PyTuple_New(2);
-        PyTuple_SetItem(pArgs, 0, PyUnicode_FromString(address_hash));
-        PyTuple_SetItem(pArgs, 1, PyLong_FromLong((long) treatment));
-        pValue = PyObject_CallObject(pyAdded, pArgs);
+        PyTuple_SetItem(pArgs, 0, PyLong_FromLong((long) router_mask_bit));
+        PyTuple_SetItem(pArgs, 1, PyLong_FromLong((long) mobile_seq));
+        pValue = PyObject_CallObject(pySetMobileSeq, pArgs);
         qd_error_py();
         Py_DECREF(pArgs);
         Py_XDECREF(pValue);
@@ -337,17 +335,17 @@
 }
 
 
-static void qd_router_mobile_removed(void *context, const char *address_hash)
+static void qd_router_set_my_mobile_seq(void *context, uint64_t mobile_seq)
 {
     qd_router_t *router = (qd_router_t*) context;
     PyObject    *pArgs;
     PyObject    *pValue;
 
-    if (pyRemoved && router->router_mode == QD_ROUTER_MODE_INTERIOR) {
+    if (pySetMobileSeq && router->router_mode == QD_ROUTER_MODE_INTERIOR) {
         qd_python_lock_state_t lock_state = qd_python_lock();
         pArgs = PyTuple_New(1);
-        PyTuple_SetItem(pArgs, 0, PyUnicode_FromString(address_hash));
-        pValue = PyObject_CallObject(pyRemoved, pArgs);
+        PyTuple_SetItem(pArgs, 0, PyLong_FromLong((long) mobile_seq));
+        pValue = PyObject_CallObject(pySetMyMobileSeq, pArgs);
         qd_error_py();
         Py_DECREF(pArgs);
         Py_XDECREF(pValue);
@@ -362,7 +360,7 @@
     PyObject    *pArgs;
     PyObject    *pValue;
 
-    if (pyRemoved && router->router_mode == QD_ROUTER_MODE_INTERIOR) {
+    if (pyLinkLost && router->router_mode == QD_ROUTER_MODE_INTERIOR) {
         qd_python_lock_state_t lock_state = qd_python_lock();
         pArgs = PyTuple_New(1);
         PyTuple_SetItem(pArgs, 0, PyLong_FromLong((long) link_mask_bit));
@@ -382,8 +380,8 @@
 
     qdr_core_route_table_handlers(router->router_core,
                                   router,
-                                  qd_router_mobile_added,
-                                  qd_router_mobile_removed,
+                                  qd_router_set_mobile_seq,
+                                  qd_router_set_my_mobile_seq,
                                   qd_router_link_lost);
 
     //
@@ -450,10 +448,10 @@
     Py_DECREF(adapterType);
     QD_ERROR_PY_RET();
 
-    pyTick = PyObject_GetAttrString(pyRouter, "handleTimerTick"); QD_ERROR_PY_RET();
-    pyAdded = PyObject_GetAttrString(pyRouter, "addressAdded"); QD_ERROR_PY_RET();
-    pyRemoved = PyObject_GetAttrString(pyRouter, "addressRemoved"); QD_ERROR_PY_RET();
-    pyLinkLost = PyObject_GetAttrString(pyRouter, "linkLost"); QD_ERROR_PY_RET();
+    pyTick           = PyObject_GetAttrString(pyRouter, "handleTimerTick"); QD_ERROR_PY_RET();
+    pySetMobileSeq   = PyObject_GetAttrString(pyRouter, "setMobileSeq"); QD_ERROR_PY_RET();
+    pySetMyMobileSeq = PyObject_GetAttrString(pyRouter, "setMyMobileSeq"); QD_ERROR_PY_RET();
+    pyLinkLost       = PyObject_GetAttrString(pyRouter, "linkLost"); QD_ERROR_PY_RET();
     return qd_error_code();
 }
 
diff --git a/tests/system_tests_interior_sync_up.py b/tests/system_tests_interior_sync_up.py
index 2b220f0..71e7f9d 100644
--- a/tests/system_tests_interior_sync_up.py
+++ b/tests/system_tests_interior_sync_up.py
@@ -129,7 +129,7 @@
         self.timer             = None
         self.poll_timer        = None
         self.delay_timer       = None
-        self.count             = 200
+        self.count             = 2000
         self.delay_count       = 12   # This should be larger than MAX_KEPT_DELTAS in mobile.py
         self.inter_router_port = inter_router_port
 
diff --git a/tests/system_tests_link_routes.py b/tests/system_tests_link_routes.py
index 4d3f61b..5730340 100644
--- a/tests/system_tests_link_routes.py
+++ b/tests/system_tests_link_routes.py
@@ -352,12 +352,12 @@
         blocking_connection = BlockingConnection(addr)
 
         # Receive on org.apache.dev
-        blocking_receiver = blocking_connection.create_receiver(address="org.apache.dev")
+        blocking_receiver = blocking_connection.create_receiver(address="org.apache.dev.1")
 
         apply_options = AtMostOnce()
 
         # Sender to  to org.apache.dev
-        blocking_sender = blocking_connection.create_sender(address="org.apache.dev", options=apply_options)
+        blocking_sender = blocking_connection.create_sender(address="org.apache.dev.1", options=apply_options)
         msg = Message(body=hello_world_2)
         # Send a message
         blocking_sender.send(msg)
@@ -371,10 +371,10 @@
         # Make sure that the router node acting as the broker (QDR.A) had one message routed through it. This confirms
         # that the message was link routed
         self.assertEqual(1, local_node.read(type='org.apache.qpid.dispatch.router.address',
-                                            name='M0org.apache.dev').deliveriesEgress)
+                                            name='M0org.apache.dev.1').deliveriesEgress)
 
         self.assertEqual(1, local_node.read(type='org.apache.qpid.dispatch.router.address',
-                                            name='M0org.apache.dev').deliveriesIngress)
+                                            name='M0org.apache.dev.1').deliveriesIngress)
 
         blocking_connection.close()
 
@@ -563,12 +563,12 @@
         blocking_connection = BlockingConnection(addr)
 
         # Receive on org.apache
-        blocking_receiver = blocking_connection.create_receiver(address="org.apache")
+        blocking_receiver = blocking_connection.create_receiver(address="org.apache.1")
 
         apply_options = AtMostOnce()
 
         # Sender to  to org.apache
-        blocking_sender = blocking_connection.create_sender(address="org.apache", options=apply_options)
+        blocking_sender = blocking_connection.create_sender(address="org.apache.1", options=apply_options)
 
         msg = Message(body=hello_world_4)
         # Send a message
@@ -583,10 +583,10 @@
         # Make sure that the router node acting as the broker (QDR.A) had one message routed through it. This confirms
         # that the message was link routed
         self.assertEqual(1, local_node.read(type='org.apache.qpid.dispatch.router.address',
-                                            name='M0org.apache').deliveriesEgress)
+                                            name='M0org.apache.1').deliveriesEgress)
 
         self.assertEqual(1, local_node.read(type='org.apache.qpid.dispatch.router.address',
-                                            name='M0org.apache').deliveriesIngress)
+                                            name='M0org.apache.1').deliveriesIngress)
 
         blocking_connection.close()
 
diff --git a/tests/system_tests_multicast.py b/tests/system_tests_multicast.py
index 1a34cd3..486d75b 100644
--- a/tests/system_tests_multicast.py
+++ b/tests/system_tests_multicast.py
@@ -558,6 +558,7 @@
                 self.r_conns[name] = conn
                 self.create_receiver(event.container, conn, self.topic, name)
                 self.n_receivers += 1
+                self.c_received[name] = 0
 
     def on_link_opened(self, event):
         if event.receiver:
@@ -720,7 +721,7 @@
 
 class MulticastPresettledRxFail(MulticastPresettled):
     """
-    Spontaineously close a receiver or connection on message received
+    Spontaneously close a receiver or connection on message received
     """
     def __init__(self, config, count, drop_clients, detach, body):
         super(MulticastPresettledRxFail, self).__init__(config, count, body, SendPresettled())
@@ -871,7 +872,7 @@
 
 class MulticastUnsettledRxFail(MulticastUnsettled3Ack):
     """
-    Spontaineously close a receiver or connection on message received
+    Spontaneously close a receiver or connection on message received
     """
     def __init__(self, config, count, drop_clients, detach, body):
         super(MulticastUnsettledRxFail, self).__init__(config, count, body)