So -- what did happen to Panix?

Fri Jan 27 11:18:55 UTC 2006

All these explanations can only go so far as to show that ConEd
and its upstreams may have had these prefixes as something that is
allowed (due to previous transit relationships) to be annnounced.
However  presumably all these were transit arrangements with ConEd
and ip blocks would have originated from different ASN where a
during the accident ConEd actually directly announced prefix as
originating from its own ASN.

One thing I can think of is that ConEd started doing syncrhonization
so all eBGP routes were redistributed into ospf or some other igp
protocol. This could led to situation that some previously configured
router that redistributes summarized rotues from igp go bgp could
think the route needs to be advertised as coming from ConEd and 
announced it Verio. But I think result of all this should have been
that route would be flapping (i.e. they start announcing and then it
gets removed from what they learn from upstream and so no longer 
redistributed to igp and no longer announced; back to the beginning) 
and they weren't.

-- 
William Leibzon
Elan Networks
william at elan.net