On Tue, Sep 19, 2000 at 03:03:53PM -0500, Dave McKay wrote:
Have you every noticed there aren't a whole lot of major IRC servers on cw.net? (I said not a whole lot, not none.) There is a reason for this, cw.net's filtering leaves something to be desired, you can advertise almost any AS to them and they will accept it. This could be used for DoS quiet easily and has been for sometime now. Blackhole attacks. But who wants to advertise an entire AS? If you peer with cw.net or most anyone for that matter you can advertise a nice little /25 on their network creating a blackhole for the amount of time you need it. This is one of the most common attacks there are. Major backbones will give major customers full routing and advertisements across their networks. (I've seen it happen, and still have it happen.)
Anyone who peers with a tier 1, particularly other tier 1s, is not easily filter. I know for a fact (having done recent turnups) that they do filter per-prefix on their downstream customers running BGP. --msa