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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: The Cidr Report
On Sat, 12 Feb 2005, Alexander Koch wrote: > > On Sat, 12 February 2005 14:58:42 +0000, Stephen J. Wilcox wrote: > > From: "Stephen J. Wilcox" <[email protected]> > > [...] - would you agree that most of the poor deaggregating is not intentional > > ie that they're announcing their '16 class Cs' or historically had 2 /21s and > > Think about someone putting in a Null0 route and re- > exporting stuff unconditionally, now after he originates > his /19 he is then adding a /24 here, and a /25 there. > Lack of experience, when you suggest to them they should > remove these announcements they are afraid to change it, > not understanding the implications, etc. > > Not to mention ppl using cisco and prefix lists, it is > way too easy with cisco to say '/19 le 24', and then they > use outbound prefix lists to their transit supplier > (different, but related as I see it). Some transit ISPs > use that a lot, and encourage the table growth. There are some business reasons to de-aggregate. Look at some outages caused by 'routing problems' (someone leaked my /24's to their peers, peers, peer and my traffic got blackholed, because the public net only knows me as a /20) There are multiple reasons for deaggregation aside from 'dumb operator', some are even 'valid' if you look at them from the protection standpoint. -Chris
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