Re: NDAA passed: Internet and Online Streaming Services Emergency Alert Study

[Michael Thomas <mike () mtcc com>]

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