RE: PI/metro/geo [Re: The state of IPv6 multihoming development]

["Tony Hain" <alh-ietf@tndh.net>]

Tony Li wrote:
> ...
> We need to decide which is more important: the scalability 
> and durability
> of the routing subsystem or the convenience of non-connection based 
> addressing.  When we have consensus on this point, then all else will
> follow.
> 

The answer to the question depends on which side of the table you are
sitting on. 

> ...
> The fact that there are already 11,000 today should concern 
> us greatly.
> If the rate of such sites continues to grow proportionally to the size
> of the network, we'd be looking at unsustainable exponential growth in
> the DFZ.  If it helps, you might recall that the DFZ about 10 
> years ago
> was only about 5K routes.  Multiplying by 20X has been painful.

Yes, but much of that is self inflicted for TE. Of the ~11,000, ~7,000
inject a single prefix, while the next ~3,000 inject 2-4. In other
words, 4/5 of the growth can be directly traced to 1/10 of the
participants.

> 
> For organizations that are looking for better/cheaper or (more likely)
> diverse service, I think that you'll agree that we do want to find
> a way to provide them service.  If we simply try to constrain the 
> topology, then we will simply be ignored.  People will use 
> the technology
> in the way that is to their benefit, not necessarily to the benefit of
> the whole.  Game theory 101.
> 
> What we must do is to give them a technological mechanism 
> that provides
> their needs, meets their cost goals and simultaneously allows 
> us to have
> a lasting routing architecture.  I believe that we have that option
> staring us in the face in the form of GSE (possibly with some 
> tweaks), but
> we need to get past our ideological differences and move 
> forward to a true
> engineering solution.
> 
> Will you help?

I have not been opposed to GSE, but I think the time has passed for it
to be adopted without coupling it with something like MIPv6 to provide a
stable identifier to the psuedo-header calculation and multi-party apps
that insist on refering addresses rather than name strings. We also need
PI address space for edge network operators that are looking for
something that can be configured into local policy databases and be
imune to changes in provider. It has been quite awhile since I looked at
the details of GSE, but if we can find a way to map a PI based HA
through the GSE context of the base header, I would be glad to help. 

Tony


> 
> Tony
>