diff --git a/ospf6d/ospf6_top.c b/ospf6d/ospf6_top.c
new file mode 100644
index 0000000..a8a058f
--- /dev/null
+++ b/ospf6d/ospf6_top.c
@@ -0,0 +1,401 @@
+/*
+ * OSPFv3 Top Level Data Structure
+ * Copyright (C) 1999 Yasuhiro Ohara
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the 
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 
+ * Boston, MA 02111-1307, USA.  
+ */
+
+#include <zebra.h>
+
+#include "log.h"
+#include "memory.h"
+#include "vty.h"
+#include "linklist.h"
+#include "prefix.h"
+#include "table.h"
+#include "thread.h"
+#include "command.h"
+
+#include "ospf6_hook.h"
+#include "ospf6_proto.h"
+#include "ospf6_prefix.h"
+#include "ospf6_lsa.h"
+#include "ospf6_lsdb.h"
+
+#include "ospf6_message.h"
+#include "ospf6_neighbor.h"
+#include "ospf6_interface.h"
+#include "ospf6_area.h"
+#include "ospf6_top.h"
+
+#include "ospf6_route.h"
+#include "ospf6_zebra.h"
+
+#include "ospf6_nsm.h"
+#include "ospf6_asbr.h"
+#include "ospf6_abr.h"
+
+#define HEADER_DEPENDENCY
+#include "ospf6d.h"
+#undef HEADER_DEPENDENCY
+
+/* global ospf6d variable */
+struct ospf6 *ospf6;
+
+static void
+ospf6_top_foreach_area (struct ospf6 *o6, void *arg, int val,
+                        void (*func) (void *, int, void *))
+{
+  listnode node;
+  struct ospf6_area *o6a;
+
+  for (node = listhead (o6->area_list); node; nextnode (node))
+    {
+      o6a = (struct ospf6_area *) getdata (node);
+      (*func) (arg, val, o6a);
+    }
+}
+
+static void
+ospf6_top_foreach_interface (struct ospf6 *o6, void *arg, int val,
+                             void (*func) (void *, int, void *))
+{
+  listnode node;
+  struct ospf6_area *o6a;
+
+  for (node = listhead (o6->area_list); node; nextnode (node))
+    {
+      o6a = (struct ospf6_area *) getdata (node);
+      (*o6a->foreach_if) (o6a, arg, val, func);
+    }
+}
+
+static void
+ospf6_top_foreach_neighbor (struct ospf6 *o6, void *arg, int val,
+                            void (*func) (void *, int, void *))
+{
+  listnode node;
+  struct ospf6_area *o6a;
+
+  for (node = listhead (o6->area_list); node; nextnode (node))
+    {
+      o6a = (struct ospf6_area *) getdata (node);
+      (*o6a->foreach_nei) (o6a, arg, val, func);
+    }
+}
+
+static int
+ospf6_top_maxage_remover (struct thread *t)
+{
+  int count;
+  struct ospf6 *o6 = (struct ospf6 *) THREAD_ARG (t);
+
+  o6->maxage_remover = (struct thread *) NULL;
+
+  count = 0;
+  o6->foreach_nei (o6, &count, NBS_EXCHANGE, ospf6_count_state);
+  o6->foreach_nei (o6, &count, NBS_LOADING, ospf6_count_state);
+  if (count != 0)
+    return 0;
+
+  ospf6_lsdb_remove_maxage (o6->lsdb);
+  return 0;
+}
+
+void
+ospf6_top_schedule_maxage_remover (void *arg, int val, struct ospf6 *o6)
+{
+  if (o6->maxage_remover != NULL)
+    return;
+
+  o6->maxage_remover =
+    thread_add_event (master, ospf6_top_maxage_remover, o6, 0);
+}
+
+void
+ospf6_show (struct vty *vty)
+{
+  listnode n;
+  struct ospf6_area *area;
+  char id_string[32];
+  unsigned long day, hour, min, sec;
+  struct timeval now, running;
+
+  /* process id, router id */
+  inet_ntop (AF_INET, &ospf6->router_id, id_string, sizeof (id_string));
+  vty_out (vty, " Routing Process (%lu) with ID %s%s",
+           ospf6->process_id, id_string, VTY_NEWLINE);
+
+  /* running time */
+  gettimeofday (&now, (struct timezone *)NULL);
+  ospf6_timeval_sub (&now, &ospf6->starttime, &running);
+  ospf6_timeval_decode (&running, &day, &hour, &min, &sec, NULL, NULL);
+  vty_out (vty, " Running %ld days %ld hours %ld minutes %ld seconds%s",
+           day, hour, min, sec, VTY_NEWLINE);
+
+  vty_out (vty, " Supports only single TOS(TOS0) routes%s", VTY_NEWLINE);
+
+  /* Redistribute config */
+  ospf6_redistribute_show_config (vty);
+
+  /* LSAs */
+  vty_out (vty, " Number of AS scoped LSAs is %u%s",
+           ospf6->lsdb->count, VTY_NEWLINE);
+  vty_out (vty, " Route calculation executed %d times%s",
+           ospf6->stat_route_calculation_execed, VTY_NEWLINE);
+
+  /* Route Statistics */
+#if 0
+  ospf6_route_statistics_show (vty, ospf6->route_table);
+#endif
+
+  /* Areas */
+  vty_out (vty, " Number of areas in this router is %u%s",
+           listcount (ospf6->area_list), VTY_NEWLINE);
+  for (n = listhead (ospf6->area_list); n; nextnode (n))
+    {
+      area = (struct ospf6_area *) getdata (n);
+      ospf6_area_show (vty, area);
+    }
+}
+
+void
+ospf6_statistics_show (struct vty *vty, struct ospf6 *o6)
+{
+  listnode node;
+  struct ospf6_area *o6a;
+  char running_time[128];
+  struct timeval now, running;
+
+  gettimeofday (&now, (struct timezone *) NULL);
+  ospf6_timeval_sub (&now, &o6->starttime, &running);
+  ospf6_timeval_string (&running, running_time, sizeof (running_time));
+
+  vty_out (vty, "Statistics of OSPF process %ld%s",
+           o6->process_id, VTY_NEWLINE);
+  vty_out (vty, "  Running: %s%s", running_time, VTY_NEWLINE);
+
+#if 0
+  ospf6_route_statistics_show (vty, o6->route_table);
+#endif
+
+  for (node = listhead (o6->area_list); node; nextnode (node))
+    {
+      o6a = (struct ospf6_area *) getdata (node);
+      ospf6_area_statistics_show (vty, o6a);
+    }
+}
+
+static struct ospf6 *
+ospf6_new ()
+{
+  struct ospf6 *new;
+  new = XMALLOC (MTYPE_OSPF6_TOP, sizeof (struct ospf6));
+  if (new)
+    memset (new, 0, sizeof (struct ospf6));
+  return new;
+}
+
+void
+ospf6_free (struct ospf6 *ospf6)
+{
+  XFREE (MTYPE_OSPF6_TOP, ospf6);
+}
+
+void
+ospf6_top_topology_add (struct ospf6_route_req *request)
+{
+  assert (request->route.type == OSPF6_DEST_TYPE_ROUTER);
+  if (CHECK_FLAG (request->path.router_bits, OSPF6_ROUTER_LSA_BIT_E))
+    ospf6_asbr_asbr_entry_add (request);
+}
+
+void
+ospf6_top_topology_remove (struct ospf6_route_req *request)
+{
+  assert (request->route.type == OSPF6_DEST_TYPE_ROUTER);
+  if (CHECK_FLAG (request->path.router_bits, OSPF6_ROUTER_LSA_BIT_E))
+    ospf6_asbr_asbr_entry_remove (request);
+}
+
+struct ospf6 *
+ospf6_create (unsigned long process_id)
+{
+  struct ospf6 *o6;
+  char namebuf[64];
+
+  o6 = ospf6_new ();
+
+  /* initialize */
+  gettimeofday (&o6->starttime, (struct timezone *)NULL);
+  o6->process_id = process_id;
+  o6->version = OSPF6_VERSION;
+  o6->area_list = list_new ();
+
+  o6->lsdb = ospf6_lsdb_create ();
+
+  o6->foreach_area = ospf6_top_foreach_area;
+  o6->foreach_if = ospf6_top_foreach_interface;
+  o6->foreach_nei = ospf6_top_foreach_neighbor;
+
+  snprintf (namebuf, sizeof (namebuf), "InterTopology table");
+  o6->topology_table = ospf6_route_table_create (namebuf);
+  ospf6_route_hook_register (ospf6_top_topology_add,
+                             ospf6_top_topology_add,
+                             ospf6_top_topology_remove,
+                             o6->topology_table);
+
+#if 0
+  snprintf (namebuf, sizeof (namebuf), "External table");
+  o6->external_table = ospf6_route_table_create (namebuf);
+  ospf6_route_hook_register (ospf6_asbr_external_route_add,
+                             ospf6_asbr_external_route_add,
+                             ospf6_asbr_external_route_remove,
+                             o6->external_table);
+#endif /*0*/
+
+  snprintf (namebuf, sizeof (namebuf), "Top route table");
+  o6->route_table = ospf6_route_table_create (namebuf);
+  ospf6_route_hook_register (ospf6_zebra_route_update_add,
+                             ospf6_zebra_route_update_add,
+                             ospf6_zebra_route_update_remove,
+                             o6->route_table);
+  ospf6_route_hook_register (ospf6_abr_route_add,
+                             ospf6_abr_route_add,
+                             ospf6_abr_route_remove,
+                             o6->route_table);
+
+  return o6;
+}
+
+void
+ospf6_delete (struct ospf6 *ospf6)
+{
+  ospf6_route_remove_all (ospf6->route_table);
+  ospf6_free (ospf6);
+}
+
+struct ospf6 *
+ospf6_start ()
+{
+  if (ospf6)
+    return ospf6;
+
+  ospf6 = ospf6_create (0);
+  return ospf6;
+}
+
+void
+ospf6_stop ()
+{
+  if (!ospf6)
+    return;
+
+  ospf6_delete (ospf6);
+  ospf6 = NULL;
+}
+
+int
+ospf6_is_asbr (struct ospf6 *o6)
+{
+  int i = 0;
+  i |= ospf6_zebra_is_redistribute (ZEBRA_ROUTE_SYSTEM);
+  i |= ospf6_zebra_is_redistribute (ZEBRA_ROUTE_CONNECT);
+  i |= ospf6_zebra_is_redistribute (ZEBRA_ROUTE_STATIC);
+  i |= ospf6_zebra_is_redistribute (ZEBRA_ROUTE_KERNEL);
+  i |= ospf6_zebra_is_redistribute (ZEBRA_ROUTE_RIPNG);
+  i |= ospf6_zebra_is_redistribute (ZEBRA_ROUTE_BGP);
+  return (i);
+}
+
+DEFUN (show_ipv6_ospf6_route,
+       show_ipv6_ospf6_route_cmd,
+       "show ipv6 ospf6 route",
+       SHOW_STR
+       IP6_STR
+       OSPF6_STR
+       "Routing table\n"
+       )
+{
+  OSPF6_CMD_CHECK_RUNNING ();
+  return ospf6_route_table_show (vty, argc, argv, ospf6->route_table);
+}
+
+ALIAS (show_ipv6_ospf6_route,
+       show_ipv6_ospf6_route_prefix_cmd,
+       "show ipv6 ospf6 route (X::X|detail)",
+       SHOW_STR
+       IP6_STR
+       OSPF6_STR
+       "Routing table\n"
+       "match IPv6 prefix\n"
+       )
+
+DEFUN (show_ipv6_ospf6_topology,
+       show_ipv6_ospf6_topology_cmd,
+       "show ipv6 ospf6 topology",
+       SHOW_STR
+       IP6_STR
+       OSPF6_STR
+       "Inter Area topology information\n"
+       )
+{
+  OSPF6_CMD_CHECK_RUNNING ();
+  return ospf6_route_table_show (vty, argc, argv, ospf6->topology_table);
+}
+
+ALIAS (show_ipv6_ospf6_topology,
+       show_ipv6_ospf6_topology_router_cmd,
+       "show ipv6 ospf6 topology (A.B.C.D|<0-4294967295>|detail)",
+       SHOW_STR
+       IP6_STR
+       OSPF6_STR
+       "Inter Area topology information\n"
+       OSPF6_ROUTER_ID_STR
+       OSPF6_ROUTER_ID_STR
+       "Detailed information\n"
+       )
+
+ALIAS (show_ipv6_ospf6_topology,
+       show_ipv6_ospf6_topology_router_lsid_cmd,
+       "show ipv6 ospf6 topology (A.B.C.D|<0-4294967295>) (A.B.C.D|<0-4294967295>)",
+       SHOW_STR
+       IP6_STR
+       OSPF6_STR
+       "Inter Area topology information\n"
+       OSPF6_ROUTER_ID_STR
+       OSPF6_ROUTER_ID_STR
+       OSPF6_LS_ID_STR
+       OSPF6_LS_ID_STR
+       )
+
+void
+ospf6_top_init ()
+{
+  install_element (VIEW_NODE, &show_ipv6_ospf6_route_cmd);
+  install_element (VIEW_NODE, &show_ipv6_ospf6_route_prefix_cmd);
+  install_element (VIEW_NODE, &show_ipv6_ospf6_topology_cmd);
+  install_element (VIEW_NODE, &show_ipv6_ospf6_topology_router_cmd);
+  install_element (VIEW_NODE, &show_ipv6_ospf6_topology_router_lsid_cmd);
+  install_element (ENABLE_NODE, &show_ipv6_ospf6_route_cmd);
+  install_element (ENABLE_NODE, &show_ipv6_ospf6_route_prefix_cmd);
+  install_element (ENABLE_NODE, &show_ipv6_ospf6_topology_cmd);
+  install_element (ENABLE_NODE, &show_ipv6_ospf6_topology_router_cmd);
+  install_element (ENABLE_NODE, &show_ipv6_ospf6_topology_router_lsid_cmd);
+}
+