On Thursday, December 11, 2014 05:55:26 PM ML wrote:
There are sloppy networks out there. If it was a big enough problem all you'd need is a few key networks drop those prefixes and we'd have a...slightly less sloppy Internet?
Router software (speaking of Cisco and Juniper in this case) has developed reasonably well that one can now strip private ASN's from the AS_PATH even though they now appear in between public ASN's. This was not possible before, as private AS filtering was only possible if they appeared contiguously in the AS_PATH. Of course, this means running later code - but chances are that if you're running code that supports 4-byte ASN's, you might have this feature. Not sure about other vendors out there. We, for example, remove private ASN's by default on all eBGP sessions. I know several other providers that do the same - but it takes a village to raise the Internet... Mark.