A /127 mask is still the best way to handle real point-to-point links like SDH/SONET today, to avoid the ping-pong problem. Works fine with Cisco and Juniper, not tried with other vendors.
I know it's immature, but I can't wait for some new hire at vendor C or vendor J to reread the RFCs and implement the all routers anycast address according to spect and then see sparks fly.
Like I said, global scope addresses on your router-to-router interfaces is such IPv4 thinking.
Global scope addresses on router-to-router interfaces are necessary today for traceroute to work. Some ISPs are *requiring* working traceroute (without MPLS hiding of intermediate hops) in RFPs to transit providers. If you can get router ICMP handling changed such that the ICMP packet generated by traceroute is sent from the loopback address, we might be able to do without global scope addresses on router-to-router interfaces. But until then... Steinar Haug, Nethelp consulting, sthaug@nethelp.no