Prepending with another ASN you don't own

Jon Lewis jlewis at
Fri Dec 16 22:22:31 UTC 2016

On Fri, 16 Dec 2016, Randy Bush wrote:

> this is called path poisoning.  an italian friend used it in his phd
> thesis.  a few friends and i used it to detect use of default across
> the internet.

I've done this in the past as a work-around for insufficient BGP community 
support.  Just prepending the AS I wanted to ignore the paths.

But, if the problem is an anycast CDN choosing a sub-optimal path to reach 
you, you might try reaching out to them.  They're probably just as, if not 
more interested, in getting their traffic to you as efficiently as 

  Jon Lewis, MCP :)           |  I route
                              |  therefore you are
_________ for PGP public key_________

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