On 1/3/21 1:50 PM, Mark Delany wrote:
On 03Jan21, Brandon Martin allegedly wrote:
I was thinking more in the original context of this thread w.r.t.
potential distribution of emergency alerts. That could, if
semi-centralized, easily result in 100s of million connections to juggle
across a single service just for the USA. While it presumably wouldn't
be quite that centralized, it's a sizable problem to manage.
Indeed. But how do you know the clients are still connected? And if they
aren't, there is
not much a server can do beyond discarding the state. Presumably the client
would need to
run a fairly frequent keep-a-live/reconnect strategy to ensure the connection
is still
functioning.
Which raises the question: how long a delay do you tolerate for an emergency
alert? I
think the end result is a lot of active connections and keep-a-live traffic.
Not really
quiescent at all. In the end, probably just as cheap to poll a CDN.
I just sent some mail to the myshakes folks at UCB asking if they have
an achitecture/network document. In their case for earthquakes it need
to be less than ~10 seconds so they are really pushing the limit. If
they get back to me, I'll share it here.
Mike
