Re: [v6ops] Stability and Resilience (was Re: A common...)

[Michael Richardson <[e-mail]>]

Lee Howard <[e-mail]> wrote:
    > 2

    > Aggregate above the provider edge device, so that grooming customers
    > between Provider Edge boxes (PEs) doesn't force a renumbering. It's been a
    > few years since I worked on CMTSs, but when I did they did not support
    > MP-BGP well (if at all), so routes had to be aggregated on the PE, or
    > leaked in the IGP which is bad for convergence time. Maybe PE vendors can
    > report.

I don't understand this comment/concern about convergence time.

I was the architect at a PE vendor (PPPoE, not CMTS, but from the north-interface, it is
pretty similar) for a numbers of years.  [2012 to 2017, parttime].

We didn't support BGP; we got no call for it as an IGP.
We supported OSPF/OSPFv3, and we assumed aggregation above the provider edge
devices. We counselled our customers to make an OSPF area for this, and
so it naturally aggregated above, and the customer grooming did not leak out
of the area.
Few of our customers' IPv6 usage grew very much during this time, so I can't
say if this turned out to be a problem.

The customers for whom this was a problem architecturally had the problem
that their network was so small that they the "above" point was their EBGP
device anyway.    We're talking about rather small ISPs with O(10^3)
customers here :-) (that would be the entire country/island)

--
Michael Richardson <[e-mail]>, Sandelman Software Works
 -= IPv6 IoT consulting =-