[j-nsp] Faster OSPF DD Exchange

Doug Marschke doug at ipath.net
Mon Dec 12 17:51:06 EST 2005


This is normal.  First have to establish "mastership" then you send out DD's
for synchronization.        



This sending and receiving of Database Description packets is
        called the "Database Exchange Process".  During this process,
        the two routers form a master/slave relationship.  Each Database
        Description Packet has a sequence number.  Database Description
        Packets sent by the master (polls) are acknowledged by the slave
        through echoing of the sequence number.  Both polls and their
        responses contain summaries of link state data.  The master is
        the only one allowed to retransmit Database Description Packets.
        It does so only at fixed intervals, the length of which is the
        configured per-interface constant RxmtInterval.

        Each Database Description contains an indication that there are
        more packets to follow --- the M-bit.  The Database Exchange
        Process is over when a router has received and sent Database
        Description Packets with the M-bit off.

        During and after the Database Exchange Process, each router has
        a list of those LSAs for which the neighbor has more up-to-date
        instances.  These LSAs are requested in Link State Request
        Packets.  Link State Request packets that are not satisfied are
        retransmitted at fixed intervals of time RxmtInterval.  When the
        Database Description Process has completed and all Link State
        Requests have been satisfied, the databases are deemed
        synchronized and the routers are marked fully adjacent.  At this
        time the adjacency is fully functional and is advertised in the
        two routers' router-LSAs.



-----Original Message-----
From: juniper-nsp-bounces at puck.nether.net
[mailto:juniper-nsp-bounces at puck.nether.net] On Behalf Of AnupKumarT 70695
Sent: Monday, December 12, 2005 5:55 AM
To: AnupKumarT 70695
Cc: juniper-nsp at puck.nether.net
Subject: [j-nsp] Faster OSPF DD Exchange

Does anybody know of OSPF peers exchanging more than 1 DD packet during
adjacency formation?

_______________________________________________
juniper-nsp mailing list juniper-nsp at puck.nether.net
http://puck.nether.net/mailman/listinfo/juniper-nsp



More information about the juniper-nsp mailing list