diff --git a/ospfd/ospf_neighbor.c b/ospfd/ospf_neighbor.c
new file mode 100644
index 0000000..a302aa9
--- /dev/null
+++ b/ospfd/ospf_neighbor.c
@@ -0,0 +1,329 @@
+/*
+ * OSPF Neighbor functions.
+ * Copyright (C) 1999, 2000 Toshiaki Takada
+ *
+ * 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 "linklist.h"
+#include "prefix.h"
+#include "memory.h"
+#include "command.h"
+#include "thread.h"
+#include "stream.h"
+#include "table.h"
+#include "log.h"
+
+#include "ospfd/ospfd.h"
+#include "ospfd/ospf_interface.h"
+#include "ospfd/ospf_asbr.h"
+#include "ospfd/ospf_lsa.h"
+#include "ospfd/ospf_lsdb.h"
+#include "ospfd/ospf_neighbor.h"
+#include "ospfd/ospf_nsm.h"
+#include "ospfd/ospf_packet.h"
+#include "ospfd/ospf_network.h"
+#include "ospfd/ospf_flood.h"
+#include "ospfd/ospf_dump.h"
+
+struct ospf_neighbor *
+ospf_nbr_new (struct ospf_interface *oi)
+{
+  struct ospf_neighbor *nbr;
+
+  /* Allcate new neighbor. */
+  nbr = XMALLOC (MTYPE_OSPF_NEIGHBOR, sizeof (struct ospf_neighbor));
+  memset (nbr, 0, sizeof (struct ospf_neighbor));
+
+  /* Relate neighbor to the interface. */
+  nbr->oi = oi;
+
+  /* Set default values. */
+  nbr->state = NSM_Down;
+
+  /* Set inheritance values. */
+  nbr->v_inactivity = OSPF_IF_PARAM (oi, v_wait);
+  nbr->v_db_desc = OSPF_IF_PARAM (oi, retransmit_interval);
+  nbr->v_ls_req = OSPF_IF_PARAM (oi, retransmit_interval);
+  nbr->v_ls_upd = OSPF_IF_PARAM (oi, retransmit_interval);
+  nbr->priority = -1;
+
+  /* DD flags. */
+  nbr->dd_flags = OSPF_DD_FLAG_MS|OSPF_DD_FLAG_M|OSPF_DD_FLAG_I;
+
+  /* Last received and sent DD. */
+  nbr->last_send = NULL;
+
+  nbr->nbr_nbma = NULL;
+
+  ospf_lsdb_init (&nbr->db_sum);
+  ospf_lsdb_init (&nbr->ls_rxmt);
+  ospf_lsdb_init (&nbr->ls_req);
+
+  nbr->crypt_seqnum = 0;
+
+  return nbr;
+}
+
+void
+ospf_nbr_free (struct ospf_neighbor *nbr)
+{
+  /* Free DB summary list. */
+  if (ospf_db_summary_count (nbr))
+    ospf_db_summary_clear (nbr);
+    /* ospf_db_summary_delete_all (nbr); */
+
+  /* Free ls request list. */
+  if (ospf_ls_request_count (nbr))
+    ospf_ls_request_delete_all (nbr);
+
+  /* Free retransmit list. */
+  if (ospf_ls_retransmit_count (nbr))
+    ospf_ls_retransmit_clear (nbr);
+
+  /* Cleanup LSDBs. */
+  ospf_lsdb_cleanup (&nbr->db_sum);
+  ospf_lsdb_cleanup (&nbr->ls_req);
+  ospf_lsdb_cleanup (&nbr->ls_rxmt);
+  
+  /* Clear last send packet. */
+  if (nbr->last_send)
+    ospf_packet_free (nbr->last_send);
+
+  if (nbr->nbr_nbma)
+    {
+      nbr->nbr_nbma->nbr = NULL;
+      nbr->nbr_nbma = NULL;
+    }
+
+  /* Cancel all timers. */
+  OSPF_NSM_TIMER_OFF (nbr->t_inactivity);
+  OSPF_NSM_TIMER_OFF (nbr->t_db_desc);
+  OSPF_NSM_TIMER_OFF (nbr->t_ls_req);
+  OSPF_NSM_TIMER_OFF (nbr->t_ls_upd);
+
+  /* Cancel all events. *//* Thread lookup cost would be negligible. */
+  thread_cancel_event (master, nbr);
+
+  XFREE (MTYPE_OSPF_NEIGHBOR, nbr);
+}
+
+/* Delete specified OSPF neighbor from interface. */
+void
+ospf_nbr_delete (struct ospf_neighbor *nbr)
+{
+  struct ospf_interface *oi;
+  struct route_node *rn;
+  struct prefix p;
+
+  oi = nbr->oi;
+
+  /* Unlink ospf neighbor from the interface. */
+  p.family = AF_INET;
+  p.prefixlen = IPV4_MAX_BITLEN;
+  p.u.prefix4 = nbr->src;
+
+  rn = route_node_lookup (oi->nbrs, &p);
+  if (rn)
+    {
+      if (rn->info)
+	{
+	  rn->info = NULL;
+	  route_unlock_node (rn);
+	}
+      else
+	zlog_info ("Can't find neighbor %s in the interface %s",
+		   inet_ntoa (nbr->src), IF_NAME (oi));
+
+      route_unlock_node (rn);
+    }
+
+  /* Free ospf_neighbor structure. */
+  ospf_nbr_free (nbr);
+}
+
+/* Check myself is in the neighbor list. */
+int
+ospf_nbr_bidirectional (struct in_addr *router_id,
+			struct in_addr *neighbors, int size)
+{
+  int i;
+  int max;
+
+  max = size / sizeof (struct in_addr);
+
+  for (i = 0; i < max; i ++)
+    if (IPV4_ADDR_SAME (router_id, &neighbors[i]))
+      return 1;
+
+  return 0;
+}
+
+/* Add self to nbr list. */
+void
+ospf_nbr_add_self (struct ospf_interface *oi)
+{
+  struct ospf_neighbor *nbr;
+  struct prefix p;
+  struct route_node *rn;
+
+  p.family = AF_INET;
+  p.prefixlen = 32;
+  p.u.prefix4 = oi->address->u.prefix4;
+
+  rn = route_node_get (oi->nbrs, &p);
+  if (rn->info)
+    {
+      /* There is already pseudo neighbor. */
+      nbr = rn->info;
+      route_unlock_node (rn);
+    }
+  else
+    rn->info = oi->nbr_self;
+}
+
+/* Get neighbor count by status.
+   Specify status = 0, get all neighbor other than myself. */
+int
+ospf_nbr_count (struct route_table *nbrs, int state)
+{
+  struct route_node *rn;
+  struct ospf_neighbor *nbr;
+  int count = 0;
+
+  /* Sanity check. */
+  if (nbrs == NULL)
+    return 0;
+
+  for (rn = route_top (nbrs); rn; rn = route_next (rn))
+    if ((nbr = rn->info) != NULL)
+      /* Ignore myself. */
+      if (!IPV4_ADDR_SAME (&nbr->router_id, &ospf_top->router_id))
+	if (state == 0 || nbr->state == state)
+	  count++;
+
+  return count;
+}
+
+#ifdef HAVE_OPAQUE_LSA
+int
+ospf_opaque_capable_nbr_count (struct route_table *nbrs, int state)
+{
+  struct route_node *rn;
+  struct ospf_neighbor *nbr;
+  int count = 0;
+
+  /* Sanity check. */
+  if (nbrs == NULL)
+    return 0;
+
+  for (rn = route_top (nbrs); rn; rn = route_next (rn))
+    if ((nbr = rn->info) != NULL)
+      /* Ignore myself. */
+      if (!IPV4_ADDR_SAME (&nbr->router_id, &ospf_top->router_id))
+	if ((state == 0 || nbr->state == state)
+	&&  CHECK_FLAG (nbr->options, OSPF_OPTION_O))
+	  count++;
+
+  return count;
+}
+#endif /* HAVE_OPAQUE_LSA */
+
+struct ospf_neighbor *
+ospf_nbr_lookup_by_addr (struct route_table *nbrs,
+			 struct in_addr *addr)
+{
+  struct prefix p;
+  struct route_node *rn;
+  struct ospf_neighbor *nbr;
+
+  p.family = AF_INET;
+  p.prefixlen = IPV4_MAX_BITLEN;
+  p.u.prefix4 = *addr;
+
+  rn = route_node_lookup (nbrs, &p);
+  if (! rn)
+    return NULL;
+
+  if (rn->info == NULL)
+    {
+      route_unlock_node (rn);
+      return NULL;
+    }
+
+  nbr = (struct ospf_neighbor *) rn->info;
+  route_unlock_node (rn);
+
+  return nbr;
+}
+
+struct ospf_neighbor *
+ospf_nbr_lookup_by_routerid (struct route_table *nbrs,
+			     struct in_addr *id)
+{
+  struct route_node *rn;
+  struct ospf_neighbor *nbr;
+
+  for (rn = route_top (nbrs); rn; rn = route_next (rn))
+    if ((nbr = rn->info) != NULL)
+      if (IPV4_ADDR_SAME (&nbr->router_id, id))
+	{
+	  route_unlock_node(rn);
+	  return nbr;
+	}
+
+  return NULL;
+}
+
+void
+ospf_renegotiate_optional_capabilities (struct ospf *top)
+{
+  listnode node;
+  struct ospf_interface *oi;
+  struct route_table *nbrs;
+  struct route_node *rn;
+  struct ospf_neighbor *nbr;
+
+  /* At first, flush self-originated LSAs from routing domain. */
+  ospf_flush_self_originated_lsas_now (top);
+
+  /* Revert all neighbor status to ExStart. */
+  for (node = listhead (top->oiflist); node; nextnode (node))
+    {
+      if ((oi = getdata (node)) == NULL || (nbrs = oi->nbrs) == NULL)
+        continue;
+
+      for (rn = route_top (nbrs); rn; rn = route_next (rn))
+        {
+          if ((nbr = rn->info) == NULL || nbr == oi->nbr_self)
+            continue;
+
+          if (nbr->state < NSM_ExStart)
+            continue;
+
+          if (IS_DEBUG_OSPF_EVENT)
+            zlog_info ("Renegotiate optional capabilities with neighbor(%s)", inet_ntoa (nbr->router_id));
+
+          OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
+        }
+    }
+
+  return;
+}