RE: (multi6) requirements draft comments

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

Andrew Partan wrote:

> > >
> > Reality says that operations people really like to believe
> they know how
> > the routers are configured.
>
> No, we don't know that 100% even today.  While I may know what
> neighbors I have configured on my routers today, I have no idea
> what routes they are actually sending me right now.  [For some
> neighbors, I may have a list of permissible routes they could send
> me, but I have no idea what they are actually sending w/o going &
> looking.]  For an IGP, I may only configure what interface to run
> over - and let the system handle the neighbor discovery.
>

Actually you made my point better than I did. Within the realm of a
trust boundary (where you would typically run an IGP) you are willing to
automate, but at the edge of that bounday, you know who is at the other
end (specifically configured) and may apply a sanity check against what
may come in from there. If we follow Noel's path, you either couldn't
know what address the neighbor was using and would have to
autoconfigure, or you have a very high cost process to manually update
everytime a customer connected to a different provider. Neither of these
fit in a typical provider/customer relationship.

> I let the routing system handle the details how to get from A to
> B after I've set up the gross overall structure.
>
> I can do analysis of how the system is supposed to work and what
> changes in face of updates, and I can put some contraints on the
> system, and adjust knobs here & there to push it more towards one
> state or another, but to know what the system is actually doing at
> any point in time, I'm going to have to go look.
>
> If we are going to scale, the system has got to be better at self
> organizing.  Yes there have to be contraints in there (aka 'knobs'),
> but the system is going to have to take on more of the work.
>
>
> When a new system rolls out, people are going to be doing a lot of
> looking at it, and set it up with all of the knobs turned way down,
> and do a lot of making sure that its doing the right thing.  [Been
> there done that with EGP/BGP switch, ospf/isis changeovers, MPLS
> deployment, others.]  But as time goes on and systems (and s/w)
> proves itself out, the knobs are loosened and you let the system
> do what it is supposed to.

This is easy to say, but since the automation is crossing a trust
boundary it is much harder to sell.

Tony