On Thu, 10 Jan 2008 10:54:22 +0100
"Miguel A. Diaz" <miguelangel.diaz@consulintel.es> wrote:
If both RA and DHPCPv6 are setup in the WAN port, the ISP has to
manage two prefix pools: one for the point-to-point link (RA) and the
other one for the delegated prefix (usually /48).
That can be avoided by getting one /64 for the point-to-point link
(RA) from the delegated prefix (/48) as explained at
http://www.consulintel.euro6ix.org/ietf/draft-palet-v6ops-point2point-
01.txt
This approach has benefits from both operational and routing
aggregation perspectives and it may be taken into account by both ISPs
and CPEs manufacturers.
I'm personally not against this addressing method, however I'm not all
that sure that might be a good idea for the customers. "Stealing" a /64
out of the customer's /48 creates opportunities for the customer to
accidently use it on their side of the CPE, breaking their external
connectivity. This probably would only happen occasionally (although as
an ISP you'd probably want to avoid the first 5, 20 or 100 /64s),
however when you have 10 000s or 100 000s customers, those occasions
can start to occur quite often, and those are calls your helpdesk has
to receive and deal with.
IOW, I think it's easier for all customers to remember, "this /48 is
mine", verses "this /48 is mine, except that one which my ISP assigns,
that I'll always have to remember to avoid."