Yasuhiro Ohara wrote:

> acee> > acee> > Do we apply any gating for MaxAge LSAs in OSPF v3. There is this
> acee> > acee> > MinLSAInterval timer which is applied to all LSA originations in OSPF v2.
> acee> > acee> > Does this hold true in OSPF v3 also? And specially for the Max Age LSAs.
> acee> > acee>
> acee> > acee> The MinLSAInterval delay is retained from OSPF v2.
> acee> > acee>
> acee> > acee> > Dont we have this concept of "Bad news fast .. Good news slow" here.
> acee> > acee>
> acee> > acee> With respect to LSA origination, MinLSAInterval is applied
> acee> > acee> equally to re-originations and purging.
> acee> >
> acee> > Actually, RFC 2328 is ambiguous about it.
> acee>
> acee> Hello Yasu,
> acee>
> acee> RFC 2328 does say that say a number of times that the "fundamental mechanisms
> acee> of OSPF (flooding, DR election, area support, etc) remain unchanged".
> acee>
> acee> > Because it does not mention about it, I think that MinLSInterval
> acee> > should not be applied to premature agings, as it lengthen the
> acee> > convergence time ... I think we should take the concept "Bad new fast".
>
> "remain unchanged" from what ? is that sentence from RFC *2740*, isn't
> it ?

>
> What I'm talking about is not the difference between OSPFv2 and
> OSPFv3.

Sorry, I misread your post. I'll use my morning excuse of not having
drunken enough coffee :-)

>
> I said "original OSPFv2 (and hence also OSPFv3) specification is
> ambiguous about whether to apply MinLSInterval when purging of LSA
> (i.e. premature aging)".

I don't think there is ambiguity in RFC 2328.

MinLSInterval is defined as the minimum time between distinct originations
of any particular LSA. When you purge an LSA you are definitely re-originating
it with a new sequence number and MaxAge.

I'm not advocating violating the specification. However is an implementation
does flood MaxAge LSAs immediatedly, it better make damn sure that the initial
origination is delayed MinLSInterval seconds after a purge. In other words,
once an LSA is purged state must be retained to assure that a new origination
is at least MinLSInterval seconds later. I'm pretty sure there are a lot of
implementations that do not retain state after an LSA is purged and
successfully flooded.

Thanks,
Acee

>
> Am I missing something ?
>
> regards,
> yasu
>
>
>

--
Acee

• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]