dynamic or static IPv6 prefixes to residential customers

Tue Aug 2 12:33:57 UTC 2011

JORDI PALET MARTINEZ <jordi.palet at consulintel.es> writes:

> I will like to know, from those deploying IPv6 services to residential
> customers, if you are planning to provide static or dynamic IPv6 prefixes.
>
> Just to be clear, I'm for static prefix delegation to residential
> customers, however I heard that some ISPs are doing dynamic delegations,
> the same way as is common today with IPv4.
>
> I don't thin it make sense, as the main reason for doing so in IPv4 was
> address exhaustion and legacy oversubscription models such as PPP/dial-up.

We will do "semi-static" PD for residential users.  In practice most
users will see this as static, but we may reallocate users if necessary
to preserve aggregation.

One point I often miss in the endless discussions wrt dynamic/static
IPv6 with references to the dynamic IPv4 world, is the lack of RFC1918
addressing for IPv6.  The fact is that all residential users are used
to, and depend on, static IPv4 addressing within their own network.
They assign e.g. 192.168.5.5 to their printer and 192.168.5.6 to their
NAS, and trust that those addresses are static.

Now moving to IPv6, their choices are either link local or a static
delegated prefix.  Link local will of course work and be completely
static for a given device, but does have a couple of drawbacks which I
believe will make most users want a static global prefix instead:
- ugly addresses, often not configurable
- the need to specify outgoing interface on any PC/whatever you want to
  talk to the link local addresss

For this reason, I argue that residential users are used to static IPv4
addresses and will demand static IPv6 addresses.  The fact that their
globally routed IPv4 address is dynamic is completely irrelevant as long
as a similar mechanism isn't available for IPv6 (no, I won't mention
NAT66). 

Bjørn