On 2012-03-17 14:37, Hemant Singh (shemant) wrote: > Arifumi, > > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of > Arifumi Matsumoto > Sent: Friday, March 16, 2012 8:30 PM > To: Brian E Carpenter > Cc: [email protected]; Brian Haberman; Bob Hinden; Dave Thaler > Subject: Re: ULA scope [draft-ietf-6man-rfc3484-revise-05.txt] > > > >> ULA-to-ULA will not be preferred, because ULAs are assigned lower > >> precedence value in the policy table than those of IPv4 and IPv6 > >> global addresses. > > > > I certainly understand if a host has an IPv4 and a ULA assigned, the > policy table prefers the IPv4 over the ULA otherwise Internet > connectivity for the host breaks down. Likewise if the host has an IPv6 > global and a ULA (which is also globally scoped), the IPv6 global is > preferred or Internet connectivity breaks down. However, the issue > that Brian raised needs some thought. The host has an IPv4, IPv6 > global, and a ULA address. What if the packet destination is a ULA for > local communication, so why not use a longest-prefix match and use a ULA > source? How does a longest-prefix match relate to the policy table? Do > we have a mode where the policy table is the only entity used for source > address selection (SAS)? If yes, then how does the ULA to ULA > communication above work?
Let me be clear. If a local service has (for some reason) both a ULA and a non-ULA global address, and the host has both, I think the correct default behaviour is for the ULA address pair to be used. This is a matter of address-pair selection, however, not of source or destination selection alone. Brian -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
