Hi Mark, > > But of course, I'm always delighted to hear your opinions. Is = > > renumbering *really* that big of a deal? I suppose multihoming is the > > = bigger, more serious concern - that's the one we see no viable > > solution = but NAT for, given small site constraints and aggregation. > > Total hogwash. Add a bit of source address based routing within the > enterprise so that you hit the right exit routers for the source address being > used. Tag route entries with valid source prefixes. > Add redirect based on source address signaling. Source based routing is a pain to maintain and to troubleshoot! In business-land I have had to pull out cruddy, unmaintainable solutions which modify normal routing behaviour and sit undocumented in various businesses. This is salient because some of the businesses are small, or started small. Please don't suggest strange addressing or routing tricks, and I will not suggest strange DNS tricks ;-) I would be OK if there was a straightforward RPF-like check which could be applied at edge routers to ensure that packets exit via the correct ISP, but my customers' routing tables are destination based, like 99% of the Internet. Greg Daley