Prefix Hijack Tool Comaprision

Todd Underwood todd at
Thu Nov 13 20:05:13 UTC 2008

alexander, all,

On Thu, Nov 13, 2008 at 07:56:26PM +0000, Alexander Harrowell wrote:
> It may be the North American NOG, but it's been said before that it
> functions as a GNOG, G for Global. I don't think Brazil is
> insignificant. I respect Todd's work greatly, but I think he's wrong
> on this point. 

you misread me.

i did not say that brazil was insignificant. it's not.  it has some of
the fastest growing internet in latin america.  

i said that *this* hijacking took place in an insignificant corner of
the internet.  i mean this AS-map wise rather than geographically.
this hijacking didn't even spread beyond one or two ASes, one of whom
just happened to be a RIPE RIS peer.  

real hijackings leak into dozens or hundreds or thousands of ASNs.
they spread far and wide.  that's why people carry them out, when they
do.  this one was stopped in its tracks in a very small portion of one
corner of the AS graph.  

as such, i don't count it as a hijacking or leak of any great
significance and wouldn't want to alert anyone about it.  that's why i
recommend that prefix hijacking detection systems do thresholding of
peers to prevent a single, rogue, unrepresentative peer from reporting
a hijacking when none is really happening.  others may have a
different approach, but without thresholding prefix alert systems can
be noisy and more trouble than they are worth.

sorry if it appears that i was denegrating .br .  i was not.


todd underwood                                 +1 603 643 9300 x101
renesys corporation                            
todd at                     

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