[ppml] Effects of explosive routing table growth on ISP behavior

[Brian Johnson]

Scott Leibrand wrote:
> 
> michael.dillon at bt.com wrote:
> >> Yes, explosive routing table growth would definitely a
> >> problem for everyone taking full BGP routes.  However, I
> >> think it's a problem that can be addressed, if/when
> >> necessary, by requiring that everyone announce their
> >> minimum-allocation-size covering aggregates, so that folks
> >> can filter out unnecessary deaggregates.
> >>
> >
> > I don't believe that it is within the scope of ARIN's charter
> > to require this. The same topic recently came up within RIPE and
> > I had a look at their terms of reference and came to the same
> > conclusion.
> >
> 
> If by "require" you mean "enforce", then you're probably right.
> However, if by "require" you mean "state what should happen" there is
> precedent: the IPv6 guidelines say you have to announce your
allocation
> as a single netblock.
> 

Question: Does it say you cannot advertise smaller portions as well as
the larger block?

> > As far as I can see, all decisions about route announcements
> > can be freely made by network operators and the only mechanism
> > for limiting this is bilateral peering agreements.
> 
> Yeah, in practice ISP filtering is the only enforcement mechanism
here.
> However, as an earlier poster pointed out, ISPs currently have nothing
> to point to if they want to tell their customers that announcing their
> covering aggregates is the right thing to do.  I think it would be
> useful for ARIN to state that such behavior is expected, either in the
> NRMP or the upcoming NPOG.

I think Michael is right on this one. ARIN needs to stay out of the
routing implications. This is getting too much into how the network is
operated, instead of the allocation of public resources.

- Brian