On Tue, Feb 04, 2014 at 10:18:21PM -0000, John Levine wrote: > I was at a conference with people from some Very Large ISPs. They > told me that many of their large customers absolutely will not let > them do BCP38 filtering. ("If you don't want our business, we can > find someone else who does.") The usual problem is that they have PA > space from two providers and for various reasons, not all of which are > stupid, traffic with provider A's addresses sometimes goes out through > provider B. Adding to the excitement, some of these customers are > medium sized ISPs with multihomed customers of their own. > > I don't know BGP well enough to know if it's possible to send out > announcements for this situtation, this address range is us, but don't > route traffic to it. Even if it is, not all of the customers do BGP, > some are just stub networks. > > If we could figure out a reasonable way (i.e., one that the customers > might be willing to implement) to handle this, it'll make BCP38 a lot > more doable.
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