Manav,

> -----Original Message-----
> From: Mailing List [mailto:OSPFDISCUSS.MICROSOFT.COM]On Behalf Of Manav
> Bhatia
> Sent: Sunday, October 20, 2002 8:12 PM
> To: OSPFDISCUSS.MICROSOFT.COM
> Subject: Re: Gating for MaxAge LSA in ospfv3
>
>
> Sina,
> We can definitely benefit from originating MaxAge LSA without waiting for
> the MinLSInterval.
>

what you call _benefit_ ? we were talking about _fast convergence_ and
announcing bad news fast

> Following are some scenarios when this might be useful.
>
> 1> A router that was formerly a DR for a network, but is now no longer,
> needs to flush the network-LSA that it had previously originated.
> I see no
> point in waiting for MinLSInterval.
>

I do not see how convergence is faster if the old DR Maxage its old network
LSA faster than MinLSInterval ?
even if the router is unable to maxage ( it is down ) it will remain for
maxage time in the database BUT the convergence is not impacted

> 3> If a router is advertising a summary-LSA/AS-External LSA for a
> destination which becomes unreachable, it needs to flush that LSA from the
> routing domain by setting its age to MaxAge and reflooding. Why should I
> wait for 5 secs to do that?

if you read my e-mail one more time ;-) you will see that I mentioned for
"type 1 and type 2".
for summary / external, sure you could maxage right away ...
also in the case of summary origination the SPF needs to be scheduled in
order to originate / maxage summary LSA therefore your LSA will be anyway
delayed ( throttled ) so there might not be a need for extra interval time

Sina

>
>
>
>
> ----- Original Message -----
> From: "Sina Mirtorabi" <sinaCISCO.COM>
> To: <OSPFDISCUSS.MICROSOFT.COM>
> Sent: Saturday, October 19, 2002 2:16 AM
> Subject: Re: Gating for MaxAge LSA in ospfv3
>
>
> > Yasu,
> >
> > > Actually, RFC 2328 is ambiguous about it.
> > > Because it does not mention about it, I think that MinLSInterval
> > > should not be applied to premature agings, as it lengthen the
> > > convergence time ... I think we should take the concept "Bad
> new fast".
> > >
> >
> >
> > although MinLSInterval is an architectural constant, implementations
> could
> > make this interval configurable ( with backoff algo ) in order to speed
> up
> > the convergence.
> >
> > now regarding Maxage LSA, it should be noted that although you
> could make
> > the bad news faster ( say by having a different interval for
> maxage LSA )
> > you will not always benefit from it ( type 1 and 2 LSA ) this is because
> > when an adj is broken or a prefix is removed you will simply originate a
> new
> > version of LSA by making the corresponding change in the content so
> having a
> > shorter interval for maxage LSA will not help there ...
> >
> > Sina

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