On Thu, 26 Oct 2006, Tony Li wrote:
It was possible to implement BCP38 before the router vendors came up with uRPF.
Further, uRPF is frequently a very inefficient means of implementing BCP 38. Consider that you're going to either compare the source address against a table of 200,000 routes or against a handful of prefixes that you've statically configured in an ACL.
Yes, I realize that the latter approach is more of a managerial hassle, but for those of you who feel that your silicon is running a tad too warm, you may wish to consider this as a possible performance improvement technique. YMMV.
Your former router vendor, Tony
Erm, most ISP's I talk to (since I became aware of this not too long ago) believe this is a perfect replacement for BCP38. And yet, spoofing is possible from their space. Gadi.