Hi,
If the LS age field of one of the router's self-originated LSAs reaches the
value LSRefreshTime (30 mins), a new instance of the LSA is originated, even
if the contents of the LSA (apart from the LSA header) are same. So if a
router has some 2000 LSAs whcih is a very nominal figure then it will
require refreshing every 1 sec with no other activity and nothing
interesting happening on the network. This periodic nature of OSPF routing
traffic requires demand circuit's underlying data-link connection to be
constantly open resulting in unwanted user charges. To avoid this "do not
age" LSAs were introduced which in theory we can press into service and are
never aged. These were introduced in rfc 1793 [OSPF over Demand Circuits].
Why is this option not being explored when dealing with scalability issues
in OSPF .. Imagine the avg refresh time if the number of LSAs go beyond
50,000 .. It would run into milliseconds ! Why are these not being
considered as a part of OSPFv3 ?
Is it because these are not backward compatible and that we need to change
the entire network before deploying this ?

Thanks and regards,
Manav

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