Re: Best way to deal with bad advertisements?

[Avi Freedman <freedman () netaxs com>]

> > In this case, the very first thing you should probably do is to
> > start announcing the more specific /24s to match their advertisements!
> > Depending on AS-PATH length (how various nets hear your announcements
> > vs. theirs) this may solve the immediate problem, allowing you to hunt
> > them down and kill them at your leisure.
>
> The downside to this is that we go from advertising /16's
> out, to advertising a fleet of /24's out, most of which 
> would be filtered by Sprint's ever-lovin' CIDR-forcing
> wall.  I agree with Sprint, and Sean, but in this case
> it pretty much makes it hard for us to force the issue
> by dropping to the same or smaller sized announcement.
>
> Good thought, though!   Even if it does result in going
> from 2 /16 announcements to 512 /24 announcements in
> the process, growing the routing tables, and generally
> making everyone else unhappy as well.

Only advertise the /24s that they're announcing of yours.
And if you need to get them into Sprint, see if a multi-
homed Sprint customer will temporarily shove them into
Sprint and static them back to you via another provider/connection.

> *sigh*  There really MUST be some nice way of handling
> lame ISP's like this.
>  
> > 1) Announce *your own* routes more specifically.
> >    This may lose you ANS connectivity, though.

I meant ANS connectivity because of RADB issues, but yes,
anyone who filters small announcements in your space won't
see you.

> I took that step last night, and was advised to remove it by
> those more in tune with legal issues.   I guess it's not
> considered "nice" to sink to the same level as your
> attacker, and play dirty.  :-}

No, but if it went on for 12 hours, I very well might do so.

> > Avi
>
> Again, my thanks for you feedback and support!
>
> Matt Petach

Sure, good luck.

And if you're going for the shunning effect, tell us all who it
is that you're having trouble with.

Avi

- - - - - - - - - - - - - - - - -