Re: [v6ops] Implementation Status of PREF64

[Gert Doering <[e-mail]>]

Hi,

On Tue, Sep 28, 2021 at 09:36:16PM +0200, Philip Homburg wrote:
> > With SLAAC, you can begin advertising an additional prefix right
> > now.
> > 
> > You cant get rid of the old one so fast, you have to wait for the
> > timers to expire.
> 
> Indeed I was sloppy. In addition to adding a prefix right now, you can 
> also deprecate the old prefix without waiting for timers to expire.
> 
> The net effect is that new flows use the new prefix right away, but the old
> prefix can be used for 2 hours longer. So timers are limited to 2 hours.

Indeed, this can be done with SLAAC.

But - the folks asking for proper DHCPv6 support in Android are not
deploying SoHo networks where ISPs tend to change prefixes every now
and then, but managed enterprise networks.  Prefixes change when the
admin says so, and they know how to deal with DHCP lease timers, 
change prefixes at times when nobody is at work, and so on.

So the standard argument from the "DHCPv6 sucks, because!" camp is
really totally ignoring reality.

(Now: supporting a DHCPv6 *server* on an Android device running as
mobile hotspot with frequently changing uplink connectivity - here I
totally agree that DHCPv6 is not the right tool for such a network
setup.  But nobody is asking for it, and refusing DHCPv6 client support
because DHCPv6 server support on the same device is not a useful
thing sounds a bit... "painted myself into a corner" -ish)

Gert Doering
        -- NetMaster
-- 
have you enabled IPv6 on something today...?

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