Re: [Webpush] Receipt subscription follow-up

[Martin Thomson <[e-mail]>]

On 26 April 2016 at 15:32, Costin Manolache <[e-mail]> wrote:
> Having one receipt subscription per region/DC may keep the number low enough
> - but there is still the issue of locality. If you send a message in US to a
> device in EU, should the PS be required to send the receipt back to US, to
> the same DC, even if there is an AS server in EU, maybe less loaded ?

That's a choice the AS gets to make.  Maybe they have some regulatory
requirements that force a particular structure.  In any case, they can
always pretend that each region is entirely separate applications and
the PS will see them as multiple different clients.

> I agree it simplifies some logic on the AS side, but what happens when
> a DC goes down  ?

I don't imagine that this is a free pass for having geographic
redundancy on the AS.  If receipts are supposed to go to EU and EU
disappears, I imagine that US will have to pick up the slack.  (More
likely that it will be between DCs in a region that this sort of
switch occurs, but you get the point.)

Maybe think of this less a simplification, but an optimization.