On Mon, Mar 12, 2012 at 11:31 AM, Leo Bicknell <bicknell@ufp.org> wrote:
In a message written on Mon, Mar 12, 2012 at 11:07:54AM -0400, Robert E. Seastrom wrote:
Grass-roots, bottom-up policy process + Need for multihoming + Got tired of waiting = IPv6 PI
It was never clear to me that even if it worked 100% as advertised that it would be cheaper / better in the global sense.
Hi Leo, When I ran the numbers a few years ago, a route had a global cost impact in the neighborhood of $8000/year. It's tough to make a case that folks who need multihoming's reliability can't afford to put that much into the system. As long as the system is largely restricted to folks who do put that much in, there's really no "problem" with the current flood-all-routers multihoming strategy: at $8k/year the demand will never again exceed the supply. A *working* multi-addressed end user system (like shim6 attempted) could solve cheap multihoming. That could have a billion dollar a year impact as folks at the leaf nodes decide they don't need the more costly BGP multihoming. But that's not where the real money is. Often overlooked is that multihoming through multi-addressing could solve IP mobility too. Provider-agnostic and media-agnostic mobility without levering off a "home" router. That's where the money is. Carry your voip call uninterrupted from your home wifi on the cable modem to your cell provider in the car to your employer's wired ethernet and back. Keep your SSH sessions alive on the notebook as you travel from home, to the airport, to London and to the hotel. Let folks access the web server on your notebook as it travels from home, to the airport, to Tokyo and back. The capability doesn't exist today. The potential economic impact of such a capability's creation is unbounded. Unfortunately, shim6 didn't work in some of the boundary cases. Since single-homing works pretty well in the ordinary case, there's not much point to a multihoming protocol that fails to deliver all the boundary cases. IIRC, the main problem was that they tried to bootstrap the layer 3 to layer 2 mapping function instead of externally requesting it. That's like trying to build ARP by making a unicast request to a local router instead of a broadcast/multicast request on the LAN. What happens when the local routers no longer have MAC addresses that you know about? Fail. Also, in complete fairness, shim6 suffered for the general lack of consumer interest in IPv6 that persists even today. It's proponents bought in to the hype that new work should focus on IPv6, and they paid for it. Regards, Bill Herrin -- William D. Herrin ................ herrin@dirtside.com bill@herrin.us 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004