> I get the impression that if NAT didn't exist, then > draft-carpenter-referral-ps would server no purpose. Is this draft > entirely motivated by problems caused by NAT?
I don't think so. There are other causes of disjoint address space, which existed even before we had NAT or specialised firewalls - router ACLs for example. Certainly NAT is the major cause today (and NPTv6 will propagate the problem into IPv6). v4-only and v6-only islands will probably arise too. Regards Brian On 08/08/2012 19:39, Curtis Villamizar wrote: > In message <[email protected]> > Brian E Carpenter writes: > >> On 07/08/2012 20:11, Michael Thomas wrote: >>> On 08/07/2012 11:46 AM, Kerry Lynn wrote: >>>> On Mon, Aug 6, 2012 at 9:39 PM, Evan Hunt <[email protected]> wrote: >>>>> Tunnels are okay, but to use them, but has to get the DNS search order >>>>> and the DNS server list right, and that's walled garden territory. >>>>> *If* we are going to turn each home into a walled garden, then let's be >>>>> aware that we are doing that. >>>> I'm of the opinion that in a "walled garden" scenario, the tunnel >>>> endpoint may >>>> be the only resource that needs a global name / address. >>> Just checking, but we all think that naming is a separate issue >>> from reachability, right? >> >> It certainly is. But see >> http://tools.ietf.org/html/draft-carpenter-referral-ps >> especially section 4.2 "FQDNs are not sufficient". >> >> Brian > > > Brian, > > MIF may be trying to solve the problem the wrong way. Providing a > mapping of DNS to loopback address has long been used (by routers) to > provide a stable reachable address. The routing cost to reach that > loopback interface (which can change many times for an active > connection) is used to determine which physical interface gets used to > reach the loopback. For example if one interface is connected to an > ethernet which gets isolated due to a router failure, the other > interface is used because routing tells us that one of them is > unreachable. > > Multihoming of course pokes holes in the routing tables and causes > some routing table bloat. This has always been a problem and IPv6 > does nothing to improve the situation that existed in IPv4 two decades > ago with a lot of small providers and large enterprises using dual > provider multihoming. > > If we are concerned with hosts that have multiple interfaces both > leading to parts of the homenet, that is easily solved. Multihomed > homenets is a whole different problem, but solvable if redundancy is > to the same provider. A conditional static route can be advertised > within the provider, with these routes having limited scope (for > example using BGP communities). If this practice were to become > commonplace (I doubt it, no consumer provider has that sort of > redundancy in the last mile), then the provider would have to limit > the scope of these more specific routes to a small subset of their own > topology. > > I get the impression that if NAT didn't exist, then > draft-carpenter-referral-ps would server no purpose. Is this draft > entirely motivated by problems caused by NAT? > > Curtis > _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
