On 31 Jan 2013, at 15:37, Andy Davidson <[email protected]> wrote: > Hi, Jon -- > > Jon Morby wrote: >> The problem is that BCP38 assumes that the ISP does some configuration >> to ensure only properly sourced packets enter their network, which >> doesn't really work unless you have a perfectly symmetrical network >> Š. and not many ISPs do > > Asymmetric routing via your non-customer peers and transit partners does > not mean you can't apply Strict uRPF facing your customers (in fact you > should do so.) > psiweb uk had correct bcp38 applied on its cisco customer routers to specifically keep bad traffic away from web service.
Colin
