Brian,
(changed topic to be more descriptive)
>> Consider cellular host case:
>> - host implements e.g. ND proxy and DHCPv6 PD for WAN connection
>> sharing
>> - host attaches to a network where only DHCPv6 happens to be used
>> - host gets single /128 IPv6 address from DHCPv6
>> - host tries to get some prefixes for its LAN interface with DHCPv6
>> PD, but network's policy rejects the prefix request
>>
>> Now what can host do? Tell user that the currently attached network
>> does not allow network connection sharing feature?
>
>Yes. The "host" in this case is actually behaving as a CPE,
>and it can report the fact that it's only able to get one address.
>
>The bug here is that the ISP is handing out a /128 instead of
>a /48, /56 or /64. That's a business issue, and the user needs
>to find a more reasonable ISP.
Well I'm not completely certain whether involving users here would
provide very good experience, and certainly operators would not be happy
to see vendors' devices complaining about limitations of their network:)
IMHO network that is giving out only /128 to hosts that are providing
"network sharing feature" is forcefully creating "localized IPv6 address
space exhaustion scenario" for the hosts, which I fear may be tackled
with mechanisms familiar from IPv4 address exhaustion scenarios, i.e.
with IPv6 NAPT.
I would not like to see IPv6 NAPT, but I see that as a real risk if
network is using DHCPv6 for allocating hosts just /128 addresses but at
the same time is not willing to delegate prefixes on demand.
Best regards,
Teemu
--------------------------------------------------------------------
IETF IPv6 working group mailing list
[email protected]
Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6
--------------------------------------------------------------------
