[ospfd] draft-ogier-ospf-dbex-opt DB-exchange optimisation

2006-08-03 Paul Jakma <paul.jakma@sun.com>

	* ospf_packet.c: (ospf_make_db_desc) Implement
	  draft-ogier-ospf-dbex-opt DB-exchange optimisation.
This commit is contained in:
Paul Jakma 2006-08-27 06:40:04 +00:00
parent 8dd24ee6d7
commit f0894cf8c3
2 changed files with 35 additions and 14 deletions

View file

@ -15,6 +15,7 @@
before deciding whether both sides are done, avoids a
needless round of empty DD packet exchanges at the end of
Exchange, hence speeding up ExchangeDone.
Implement draft-ogier-ospf-dbex-opt DB-exchange optimisation.
(ospf_db_desc) use UNSET_FLAG macro.
2006-07-27 Andrew J. Schorr <ajschorr@alumni.princeton.edu>

View file

@ -1035,20 +1035,40 @@ ospf_db_desc_proc (struct stream *s, struct ospf_interface *oi,
/* Lookup received LSA, then add LS request list. */
find = ospf_lsa_lookup_by_header (oi->area, lsah);
if (!find || ospf_lsa_more_recent (find, new) < 0)
{
ospf_ls_request_add (nbr, new);
ospf_lsa_discard (new);
}
else
{
/* Received LSA is not recent. */
if (IS_DEBUG_OSPF_EVENT)
zlog_debug ("Packet [DD:RECV]: LSA received Type %d, "
"ID %s is not recent.", lsah->type, inet_ntoa (lsah->id));
ospf_lsa_discard (new);
continue;
}
/* ospf_lsa_more_recent is fine with NULL pointers */
switch (ospf_lsa_more_recent (find, new))
{
case -1:
/* Neighbour has a more recent LSA, we must request it */
ospf_ls_request_add (nbr, new);
case 0:
/* If we have a copy of this LSA, it's either less recent
* and we're requesting it from neighbour (the case above), or
* it's as recent and we both have same copy (this case).
*
* In neither of these two cases is there any point in
* describing our copy of the LSA to the neighbour in a
* DB-Summary packet, if we're still intending to do so.
*
* See: draft-ogier-ospf-dbex-opt-00.txt, describing the
* backward compatible optimisation to OSPF DB Exchange /
* DB Description process implemented here.
*/
if (find)
ospf_lsdb_delete (&nbr->db_sum, find);
ospf_lsa_discard (new);
break;
default:
/* We have the more recent copy, nothing specific to do:
* - no need to request neighbours stale copy
* - must leave DB summary list copy alone
*/
if (IS_DEBUG_OSPF_EVENT)
zlog_debug ("Packet [DD:RECV]: LSA received Type %d, "
"ID %s is not recent.", lsah->type, inet_ntoa (lsah->id));
ospf_lsa_discard (new);
}
}
/* Master */