diff --git a/ospf6d/ospf6_abr.c b/ospf6d/ospf6_abr.c
index c3a63fe..3277e7d 100644
--- a/ospf6d/ospf6_abr.c
+++ b/ospf6d/ospf6_abr.c
@@ -253,7 +253,7 @@
     }
 
   /* do not generate if the route cost is greater or equal to LSInfinity */
-  if (route->path.cost >= LS_INFINITY)
+  if (route->path.cost >= OSPF_LS_INFINITY)
     {
       if (is_debug)
         zlog_debug ("The cost exceeds LSInfinity, withdraw");
@@ -296,7 +296,7 @@
       /* ranges are ignored when originate backbone routes to transit area.
          Otherwise, if ranges are configured, the route is suppressed. */
       if (range && ! CHECK_FLAG (range->flag, OSPF6_ROUTE_REMOVE) &&
-          (route->path.area_id != BACKBONE_AREA_ID ||
+          (route->path.area_id != OSPF_AREA_BACKBONE ||
            ! IS_AREA_TRANSIT (area)))
         {
           if (is_debug)
@@ -604,7 +604,7 @@
     }
 
   /* (1) if cost == LSInfinity or if the LSA is MaxAge */
-  if (cost == LS_INFINITY)
+  if (cost == OSPF_LS_INFINITY)
     {
       if (is_debug)
         zlog_debug ("cost is LS_INFINITY, ignore");
diff --git a/ospf6d/ospf6_area.c b/ospf6d/ospf6_area.c
index 9934e6b..2d20e62 100644
--- a/ospf6d/ospf6_area.c
+++ b/ospf6d/ospf6_area.c
@@ -401,6 +401,7 @@
     }
 
   ospf6_route_remove (range, oa->range_table);
+
   return CMD_SUCCESS;
 }
 
diff --git a/ospf6d/ospf6_area.h b/ospf6d/ospf6_area.h
index e8a4fbd..655967a 100644
--- a/ospf6d/ospf6_area.h
+++ b/ospf6d/ospf6_area.h
@@ -105,8 +105,6 @@
 #define OSPF6_AREA_TRANSIT    0x04 /* TransitCapability */
 #define OSPF6_AREA_STUB       0x08
 
-#define BACKBONE_AREA_ID (htonl (0))
-#define IS_AREA_BACKBONE(oa) ((oa)->area_id == BACKBONE_AREA_ID)
 #define IS_AREA_ENABLED(oa) (CHECK_FLAG ((oa)->flag, OSPF6_AREA_ENABLE))
 #define IS_AREA_ACTIVE(oa) (CHECK_FLAG ((oa)->flag, OSPF6_AREA_ACTIVE))
 #define IS_AREA_TRANSIT(oa) (CHECK_FLAG ((oa)->flag, OSPF6_AREA_TRANSIT))
diff --git a/ospf6d/ospf6_asbr.c b/ospf6d/ospf6_asbr.c
index ae0a286..1a0634e 100644
--- a/ospf6d/ospf6_asbr.c
+++ b/ospf6d/ospf6_asbr.c
@@ -174,7 +174,7 @@
       return;
     }
 
-  if (OSPF6_ASBR_METRIC (external) == LS_INFINITY)
+  if (OSPF6_ASBR_METRIC (external) == OSPF_LS_INFINITY)
     {
       if (IS_OSPF6_DEBUG_EXAMIN (AS_EXTERNAL))
         zlog_debug ("Ignore LSA with LSInfinity Metric");
@@ -890,7 +890,7 @@
   u_int32_t metric;
   char *endp;
   metric = strtoul (arg, &endp, 0);
-  if (metric > LS_INFINITY || *endp != '\0')
+  if (metric > OSPF_LS_INFINITY || *endp != '\0')
     return NULL;
   return XSTRDUP (MTYPE_ROUTE_MAP_COMPILED, arg);
 }
diff --git a/ospf6d/ospf6_flood.c b/ospf6d/ospf6_flood.c
index b815972..3a9af01 100644
--- a/ospf6d/ospf6_flood.c
+++ b/ospf6d/ospf6_flood.c
@@ -113,7 +113,7 @@
   ospf6_lsdb_add (ospf6_lsa_copy (lsa), lsdb_self);
 
   lsa->refresh = thread_add_timer (master, ospf6_lsa_refresh, lsa,
-                                   LS_REFRESH_TIME);
+                                   OSPF_LS_REFRESH_TIME);
 
   if (IS_OSPF6_DEBUG_LSA_TYPE (lsa->header->type) ||
       IS_OSPF6_DEBUG_ORIGINATE_TYPE (lsa->header->type))
@@ -228,7 +228,7 @@
   quagga_gettime (QUAGGA_CLK_MONOTONIC, &now);
   if (! OSPF6_LSA_IS_MAXAGE (lsa))
     lsa->expire = thread_add_timer (master, ospf6_lsa_expire, lsa,
-                                    MAXAGE + lsa->birth.tv_sec - now.tv_sec);
+                                    OSPF_LSA_MAXAGE + lsa->birth.tv_sec - now.tv_sec);
   else
     lsa->expire = NULL;
 
@@ -837,7 +837,7 @@
           struct timeval now, res;
           quagga_gettime (QUAGGA_CLK_MONOTONIC, &now);
           timersub (&now, &old->installed, &res);
-          if (res.tv_sec < MIN_LS_ARRIVAL)
+          if (res.tv_sec < OSPF_MIN_LS_ARRIVAL)
             {
               if (is_debug)
                 zlog_debug ("LSA can't be updated within MinLSArrival, discard");
@@ -944,7 +944,7 @@
       /* If database copy is in 'Seqnumber Wrapping',
          simply discard the received LSA */
       if (OSPF6_LSA_IS_MAXAGE (old) &&
-          old->header->seqnum == htonl (MAX_SEQUENCE_NUMBER))
+          old->header->seqnum == htonl (OSPF_MAX_SEQUENCE_NUMBER))
         {
           if (is_debug)
             {
diff --git a/ospf6d/ospf6_interface.c b/ospf6d/ospf6_interface.c
index 40cda24..467479b 100644
--- a/ospf6d/ospf6_interface.c
+++ b/ospf6d/ospf6_interface.c
@@ -112,9 +112,9 @@
   oi->transdelay = OSPF6_INTERFACE_TRANSDELAY;
   oi->priority = OSPF6_INTERFACE_PRIORITY;
 
-  oi->hello_interval = OSPF6_INTERFACE_HELLO_INTERVAL;
-  oi->dead_interval = OSPF6_INTERFACE_DEAD_INTERVAL;
-  oi->rxmt_interval = OSPF6_INTERFACE_RXMT_INTERVAL;
+  oi->hello_interval = OSPF_HELLO_INTERVAL_DEFAULT;
+  oi->dead_interval = OSPF_ROUTER_DEAD_INTERVAL_DEFAULT;
+  oi->rxmt_interval = OSPF_RETRANSMIT_INTERVAL_DEFAULT;
   oi->cost = OSPF6_INTERFACE_COST;
   oi->state = OSPF6_INTERFACE_DOWN;
   oi->flag = 0;
diff --git a/ospf6d/ospf6_lsa.c b/ospf6d/ospf6_lsa.c
index ff061df..7dbd303 100644
--- a/ospf6d/ospf6_lsa.c
+++ b/ospf6d/ospf6_lsa.c
@@ -139,11 +139,11 @@
 
   ospf6_lsa_age_current (lsa1);
   ospf6_lsa_age_current (lsa2);
-  if (ntohs (lsa1->header->age) == MAXAGE &&
-      ntohs (lsa2->header->age) != MAXAGE)
+  if (ntohs (lsa1->header->age) == OSPF_LSA_MAXAGE &&
+      ntohs (lsa2->header->age) != OSPF_LSA_MAXAGE)
     return 1;
-  if (ntohs (lsa1->header->age) != MAXAGE &&
-      ntohs (lsa2->header->age) == MAXAGE)
+  if (ntohs (lsa1->header->age) != OSPF_LSA_MAXAGE &&
+      ntohs (lsa2->header->age) == OSPF_LSA_MAXAGE)
     return 1;
 
   /* compare body */
@@ -218,19 +218,19 @@
     zlog_warn ("LSA: quagga_gettime failed, may fail LSA AGEs: %s",
                safe_strerror (errno));
 
-  if (ntohs (lsa->header->age) >= MAXAGE)
+  if (ntohs (lsa->header->age) >= OSPF_LSA_MAXAGE)
     {
       /* ospf6_lsa_premature_aging () sets age to MAXAGE; when using
          relative time, we cannot compare against lsa birth time, so
          we catch this special case here. */
-      lsa->header->age = htons (MAXAGE);
-      return MAXAGE;
+      lsa->header->age = htons (OSPF_LSA_MAXAGE);
+      return OSPF_LSA_MAXAGE;
     }
   /* calculate age */
   ulage = now.tv_sec - lsa->birth.tv_sec;
 
   /* if over MAXAGE, set to it */
-  age = (ulage > MAXAGE ? MAXAGE : ulage);
+  age = (ulage > OSPF_LSA_MAXAGE ? OSPF_LSA_MAXAGE : ulage);
 
   lsa->header->age = htons (age);
   return age;
@@ -243,8 +243,8 @@
   unsigned short age;
 
   age = ospf6_lsa_age_current (lsa) + transdelay;
-  if (age > MAXAGE)
-    age = MAXAGE;
+  if (age > OSPF_LSA_MAXAGE)
+    age = OSPF_LSA_MAXAGE;
   lsa->header->age = htons (age);
 }
 
@@ -258,7 +258,7 @@
   THREAD_OFF (lsa->expire);
   THREAD_OFF (lsa->refresh);
 
-  lsa->header->age = htons (MAXAGE);
+  lsa->header->age = htons (OSPF_LSA_MAXAGE);
   thread_execute (master, ospf6_lsa_expire, lsa, 0);
 }
 
@@ -297,15 +297,15 @@
   ageb = ospf6_lsa_age_current (b);
 
   /* MaxAge check */
-  if (agea == MAXAGE && ageb != MAXAGE)
+  if (agea == OSPF_LSA_MAXAGE && ageb != OSPF_LSA_MAXAGE)
     return -1;
-  else if (agea != MAXAGE && ageb == MAXAGE)
+  else if (agea != OSPF_LSA_MAXAGE && ageb == OSPF_LSA_MAXAGE)
     return 1;
 
   /* Age check */
-  if (agea > ageb && agea - ageb >= MAX_AGE_DIFF)
+  if (agea > ageb && agea - ageb >= OSPF_LSA_MAXAGE_DIFF)
     return 1;
-  else if (agea < ageb && ageb - agea >= MAX_AGE_DIFF)
+  else if (agea < ageb && ageb - agea >= OSPF_LSA_MAXAGE_DIFF)
     return -1;
 
   /* neither recent */
@@ -653,7 +653,7 @@
   new = ospf6_lsa_create (self->header);
   new->lsdb = old->lsdb;
   new->refresh = thread_add_timer (master, ospf6_lsa_refresh, new,
-                                   LS_REFRESH_TIME);
+                                   OSPF_LS_REFRESH_TIME);
 
   /* store it in the LSDB for self-originated LSAs */
   ospf6_lsdb_add (ospf6_lsa_copy (new), lsdb_self);
diff --git a/ospf6d/ospf6_lsa.h b/ospf6d/ospf6_lsa.h
index 263411f..f10ee67 100644
--- a/ospf6d/ospf6_lsa.h
+++ b/ospf6d/ospf6_lsa.h
@@ -107,7 +107,7 @@
   ((L)->header->adv_router == (a) && (L)->header->id == (i) && \
    (L)->header->type == (t))
 #define OSPF6_LSA_IS_DIFFER(L1, L2)  ospf6_lsa_is_differ (L1, L2)
-#define OSPF6_LSA_IS_MAXAGE(L) (ospf6_lsa_age_current (L) == MAXAGE)
+#define OSPF6_LSA_IS_MAXAGE(L) (ospf6_lsa_age_current (L) == OSPF_LSA_MAXAGE)
 #define OSPF6_LSA_IS_CHANGED(L1, L2) ospf6_lsa_is_changed (L1, L2)
 
 struct ospf6_lsa
diff --git a/ospf6d/ospf6_lsdb.c b/ospf6d/ospf6_lsdb.c
index 280bdf9..7455d83 100644
--- a/ospf6d/ospf6_lsdb.c
+++ b/ospf6d/ospf6_lsdb.c
@@ -572,7 +572,7 @@
   /* if current database copy not found, return InitialSequenceNumber */
   lsa = ospf6_lsdb_lookup (type, id, adv_router, lsdb);
   if (lsa == NULL)
-    seqnum = INITIAL_SEQUENCE_NUMBER;
+    seqnum = OSPF_INITIAL_SEQUENCE_NUMBER;
   else
     seqnum = (signed long) ntohl (lsa->header->seqnum) + 1;
 
diff --git a/ospf6d/ospf6_message.c b/ospf6d/ospf6_message.c
index 5edb70c..b35aa1a 100644
--- a/ospf6d/ospf6_message.c
+++ b/ospf6d/ospf6_message.c
@@ -1282,7 +1282,7 @@
   {
     if (IS_OSPF6_DEBUG_MESSAGE (oh->type, RECV))
     {
-      if (oh->area_id == BACKBONE_AREA_ID)
+      if (oh->area_id == OSPF_AREA_BACKBONE)
         zlog_debug ("%s: Message may be via Virtual Link: not supported", __func__);
       else
         zlog_debug
diff --git a/ospf6d/ospf6_network.c b/ospf6d/ospf6_network.c
index e5a1436..eed7f9d 100644
--- a/ospf6d/ospf6_network.c
+++ b/ospf6d/ospf6_network.c
@@ -27,6 +27,7 @@
 #include "sockopt.h"
 #include "privs.h"
 
+#include "libospf.h"
 #include "ospf6_proto.h"
 #include "ospf6_network.h"
 
diff --git a/ospf6d/ospf6_proto.h b/ospf6d/ospf6_proto.h
index 6462500..af60eb9 100644
--- a/ospf6d/ospf6_proto.h
+++ b/ospf6d/ospf6_proto.h
@@ -26,33 +26,12 @@
 /* OSPF protocol version */
 #define OSPFV3_VERSION           3
 
-/* OSPF protocol number. */
-#ifndef IPPROTO_OSPFIGP
-#define IPPROTO_OSPFIGP         89
-#endif
-
 /* TOS field normaly null */
 #define DEFAULT_TOS_VALUE      0x0
 
-/* Architectural Constants */
-#define LS_REFRESH_TIME                1800  /* 30 min */
-#define MIN_LS_INTERVAL                   5
-#define MIN_LS_ARRIVAL                    1
-#define MAXAGE                         3600  /* 1 hour */
-#define CHECK_AGE                       300  /* 5 min */
-#define MAX_AGE_DIFF                    900  /* 15 min */
-#define LS_INFINITY                0xffffff  /* 24-bit binary value */
-#define INITIAL_SEQUENCE_NUMBER  0x80000001  /* signed 32-bit integer */
-#define MAX_SEQUENCE_NUMBER      0x7fffffff  /* signed 32-bit integer */
-
 #define ALLSPFROUTERS6 "ff02::5"
 #define ALLDROUTERS6   "ff02::6"
 
-/* Configurable Constants */
-
-#define DEFAULT_HELLO_INTERVAL       10
-#define DEFAULT_ROUTER_DEAD_INTERVAL 40
-
 #define OSPF6_ROUTER_BIT_W     (1 << 3)
 #define OSPF6_ROUTER_BIT_V     (1 << 2)
 #define OSPF6_ROUTER_BIT_E     (1 << 1)
diff --git a/ospf6d/ospf6d.h b/ospf6d/ospf6d.h
index 2ac6300..13699d6 100644
--- a/ospf6d/ospf6d.h
+++ b/ospf6d/ospf6d.h
@@ -24,6 +24,9 @@
 
 #define OSPF6_DAEMON_VERSION    "0.9.7r"
 
+#include "libospf.h"
+#include "thread.h"
+
 /* global variables */
 extern struct thread_master *master;