Re: (multi6) requirements draft comments

[Andrew Partan <asp@partan.com>]

On Fri, Dec 21, 2001 at 09:46:58AM -0800, Tony Hain wrote:
> > No, not if the system does the work for you.  Managing the topology
> > abstractions is something the system should do, not people.
> >
> 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.

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.

> > > > the users have to renumber when they change providers, and
> > >
> > > Actually they have to renumber everytime their neighbors change
> > > providers as well, because the entire graph changes around them.
> >
> > No, only if they change their attachment point.  If your neighor
> > changes his attachment point, he renumbers, not you.
> 
> If he changes the entire graph so that it does not fit neatly in the
> aggrigate, then everyone who is disrupted in the more granular space
> will have to readdress.

If you move, you have to change your info, but no one else does.
	--asp