On Oct 21, 2010, at 3:15 PM, Mark Andrews wrote: > > In message <e22a56b3-68f1-4a75-a091-e416800c4...@delong.com>, Owen DeLong > write > s: >>>>> >>>> Which is part one of the three things that have to happen to make ULA >>>> really bad for the internet. >>>> >>>> Part 2 will be when the first provider accepts a large sum of money to >>>> route it within their public network between multiple sites owned by >>>> the same customer. >>>> >>> >>> That same customer is also going to have enough global address >>> space to be able to reach other global destinations, at least enough >>> space for all nodes that are permitted to access the Internet, if not >>> more. Proper global address space ensures that if a global destination >>> is reachable, then there is a high probability of successfully reaching >>> it. The scope of external ULA reachability, regardless of how much >>> money is thrown at the problem, isn't going to be as good as proper >>> global addresses. >>> >> _IF_ they implement as intended and as documented. As you've >> noted there's a lot of confusion and a lot of people not reading the >> documents, latching onto ULA and deciding ti's good. >> >> It's not a big leap for some company to do a huge ULA deployment >> saying "this will never connect to the intarweb thingy" and 5-10 years >> later not want to redeploy all their addressing, so, they start throwing >> money at getting providers to do what they shouldn't instead of >> readdressing their networks. > > IPv4 think. > > You don't re-address you add a new address to every node. IPv6 is > designed for multiple addresses. > That's a form of re-addressing. It's not removing the old addresses, but, it is a major undertaking just the same in a large deployment.
>>> For private site interconnect, I'd think it more likely that the >>> provider would isolate the customers traffic and ULA address space via >>> something like a VPN service e.g. MPLS, IPsec. >>> >> One would hope, but, I bet laziness and misunderstanding trumps >> reason and adherence to RFCs over the long term. Since ULA >> won't get hard-coded into routers as unroutable (it can't), > > Actually it can be. You just need a easy switch to turn it off. The > router can even work itself out many times. Configure multiple interfaces > from the same ULA /48 and you pass traffic for the /48 between those > interfaces. You also pass routes for that /48 via those interfaces. > If you have an easy switch to turn it off, it will get used, thus meaning that it isn't hard coded, it's just default. > Owen
