Subject: OSPFv3 Future Extendibility

From: Acee Lindem <[email-masked]>
Date: Thu, 24 Feb 2005 17:15:32 -0500

At the Washington IETF, draft-mirtorabi-mt-ospfv3-01.txt was  presented.
While the goal of the draft is to support multi-topologies with a single 
OSPFv3
instance,  the draft introduced the concept of  TLV-based OSPFv3 LSAs in
addition to the existing base RFC 2740 types. I was hoping this would 
generate
more discussion but heretofore it has not.

I see this as a very important decision with respect to the future of 
direction
of OSPFv3 and believe it goes beyond multi-topology support. I would 
support
this draft as I believe it will make our work easier in the future and 
eliminate the
main advantage of ISIS over OSPF. Solutions involving carrying additional
attributes in ancillary LSAs will always suffer from the issues involved 
with
synchronizing the base LSA with the additional information in the new LSAs.
So let's begin this discussion and I'm also thinking of reserving some time
on OSPF WG agenda since I'd expect there will be interest.

As for positioning versus draft-ietf-ospf-af-alt-01.txt, we will move 
forward
with this draft as it provides a low implementation cost solution and 
isolation
between address families via separate instance. BGP allows both today 
(i.e.,
support for multiple address families per session or separate of address
families between sessions).

Thanks,
Acee

---

From: Tony Przygienda <[email-masked]>
Date: Thu, 24 Feb 2005 23:52:33 +0000

> families between sessions).

As to BGP, the isolation suffers (-ed) from the fact that different 
families are normally
carried on the same session and interesting priotization problems under 
load occur. That
also causes as
well non-trivial implementation/spec issues to avoid
synchronization-loss/error  handling  cross-talk between families. 
Reading your
draft that does not seem to happen but just keep that in mind when 
moving things
forward, I would suggest, so it doesn't creep in ...

      thanks

    -- tony

---

From: Acee Lindem <[email-masked]>
Date: Thu, 24 Feb 2005 20:28:15 -0500

Tony Przygienda wrote:

> carried on the same session and interesting priotization problems 
> under load occur. That
> also causes as

Hi Tony,
Your comment on BGP is a good argument with going forward with the existing
WG document. If you have suggestions or things that should be clarified 
in the
OSPFv3 MT draft, please don't hesitate to bring them up. Of particular 
interest
would be rules for encoding TLVs that would have made life easier had 
they been
imposed from day one in ISIS or BGP.

Thanks,
Acee