I don't quite see the DFZ table problem or 'PI-problem' with ULA if route filtering is done properly. The theoretical problem arises by ISP/NSP not filtering 'private' prefixes and other trash. For example in v4 DFZ table private ASN can be seen forwarded even by large ISP. If ULA's become routed and therefore usable as replacement for PI it is caused by lash filtering. Prefixes not intended/assigned/allocated for public/global use are to be filtered. In case the uplink ISP accepts an ULA prefix into the routing table *he* has to deal with his customers reachability problems. Imho some sort of PI is required to be supported in v6, and either way to assign it is fine. But it has to be kept distinguished from any RFC1918 equivalent to allow for filtering of private addresses. greetz, Marcus ------------------------------------------------------------------------------------------------ Systemtechnik Internet / Internet Engineering Versatel West-Deutschland GmbH Versatel-Gruppe Unterste-Wilms-Strasse 29 D-44143 Dortmund Sitz der Gesellschaft: Berlin, Amtsgericht Charlottenburg, HRB 94994 B Geschäftsführer: Peer Knauer, Hai Cheng, Brian Cook, Marc Lützenkirchen, Christian Schemann Fon: +49-(0)231-399-4486 | Fax: +49-(0)231-399-4491 marcus.gerdon@versatel.de | www.versatel.de ------------------------------------------------------------------------------------------------ AS8881 / AS8638 / AS15837 | MG3031-RIPE ------------------------------------------------------------------------------------------------ -----Ursprüngliche Nachricht----- Von: address-policy-wg-admin@ripe.net [mailto:address-policy-wg-admin@ripe.net] Im Auftrag von Shane Kerr Gesendet: Montag, 14. Mai 2007 09:51 An: bmanning@karoshi.com Cc: ppml@arin.net; address-policy-wg@ripe.net Betreff: Re: [address-policy-wg] Re: [ppml] article about IPv6 vs firewalls vs NAT in arstechnica (seen on slashdot) On Mon, May 14, 2007 at 05:30:40AM +0000, bmanning@karoshi.com wrote:

...

ULA-central is NOT intended to be uses as IPv6 PI.

but there is no way to stop it from becoming so.

In the same way that RFC 1918 space is such a huge problem for the IPv4 routing table, ULA-central would be a problem in IPv6. (I think ULA-central is completely unnecessary, but I also think the "oh mi gawd IPv6 PI!!!1" argument is bogus.) -- Shane