"ms" == Marc Slemko <marcs@znep.com> writes: [...] This could be a tricky way for someone to just use whatever otherwise unannounced space in 64/8, or it could just be a lame router configuration somewhere that the parties involved don't care to fix.
Certainly the latter (never attribute to malice what can be explained with stupidity). It's just too easy to forget "no auto-summary", and too difficult to notice its effects - you'll attract traffic from unused addresses under the classful prefix (64.0.0.0/8 in this case), but there shouldn't be that much of it. Of course once in a while when a network using a more-specific prefix goes offline for a while, you may receive quite a bit of unexpected traffic. But I bet that most ISPs don't have good tools to detect this either. So we have to wait until a nice person signals the problem to the offender. For 64.0.0.0/8 this seems to have happened in the meantime... but now there's a route for 62.0.0.0/8 (the RIPE equivalent of 64.0.0.0/8), sigh. -- Simon.