In RFC2328, last part of chapter 10.5 it reads:
o Each Hello Packet causes the neighbor state machine to be
executed with the event HelloReceived.
o Then the list of neighbors contained in the Hello Packet is
examined. If the router itself appears in this list, the
neighbor state machine should be executed with the event 2-
WayReceived. Otherwise, the neighbor state machine should
be executed with the event 1-WayReceived, and the processing
of the packet stops.
o Next, if a change in the neighbor's Router Priority field
was noted, the receiving interface's state machine is
scheduled with the event NeighborChange.
o If the neighbor is both declaring itself to be Designated
Router (Hello Packet's Designated Router field = Neighbor IP
address) and the Backup Designated Router field in the
packet is equal to 0.0.0.0 and the receiving interface is in
state Waiting, the receiving interface's state machine is
scheduled with the event BackupSeen. Otherwise, if the
neighbor is declaring itself to be Designated Router and it
had not previously, or the neighbor is not declaring itself
Designated Router where it had previously, the receiving
interface's state machine is scheduled with the event
NeighborChange.
o If the neighbor is declaring itself to be Backup Designated
Router (Hello Packet's Backup Designated Router field =
Neighbor IP address) and the receiving interface is in state
Waiting, the receiving interface's state machine is
scheduled with the event BackupSeen. Otherwise, if the
neighbor is declaring itself to be Backup Designated Router
and it had not previously, or the neighbor is not declaring
itself Backup Designated Router where it had previously, the
receiving interface's state machine is scheduled with the
event NeighborChange.
Some questions:
1) Is it important that the above events are generated in this order? Is moving
HelloReceived futher down allowed?
2) Following this list to the letter it seems that one could generate the same
event several times. There could be 3 NeighborChange and 2 BackupSeen, is
this
the intentions or is it enough to generate each type at most once?
Jocke
_______________________________________________
OSPF mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/ospf
