IPv4 source routing options and IPv6 Type 0 Routing Header

John Osmon josmon at rigozsaurus.com
Mon Jun 30 14:10:46 CDT 2008


On Mon, Jun 30, 2008 at 06:35:12PM +0100, Sam Stickland wrote:
> Can someone give an example of how to use source routing to check a 
> peers routing policy?


Channelling from a similar private conversation I had many years ago:

   Seeing if packets directed to prefixes that you're not announcing come
   back to you is interesting (and can be an indicator that someone is
   pointing default at you). Seeing if packets directed to prefixes you
   *are* announcing *do* come back to you is also interesting.


So, an example might be to send a traceroute across a peer's link
via source routing, and watching the result.




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