[aprssig] Re: Cell phone and Pager alerts

[Robert Bruninga]

Good points.  If this system uses a broadcast protocol so
that is targeted to specific info at specific geographical
areas say per "cell phone cell", and the bandwidth is just
the one message that then hits all subscribers in the cell
without the one-to-one-ack-required, then I can see how
it could be very effective.

Which reminds me of why we have been so unsuccessful
with HAM paging.  It is trivial to convert a pager over 
to HAM freqs and to transmit the paging signals
(The KPC-3+ can do it).  I always thought that would be
a nice Amateur Radio project.  Maybe not economically
practical, but fun to do.  (the hobby aspect that is)...

Bob

>>> kc2mmi at verizon.net 02/02/06 2:57 PM >>>
Bob-
 <<I take offense at your post.>>
 No offense intended. Of course there was nothing in your post to outright
*suggest* anything specific...but your post only asked "whats wrong" it didn't
state much of anything. That leaves people to ask, why should there be anything
wrong in the first place? Where is the question coming from?

<<And there was nothing sniggling.>>
 My post wasn't made specifically to you. I've heard too many hams denigrate
"civilian" communications and their shortcomings though, and I was addressing
that attitude in general, not saying you had it.

<<The point I was
making was that flooding comms networks with hundreds
of Thousands if not millions of one-to-one emails and text
messages might just not be the  smartest way for mass
announcements.>>
 Well, let's take a case in point. A small country that has been at war for the
past 50+ years and has most of their citizens "on alert" formally or informally
24x7x365. Israel.
 If you went to Israel in the 60's or 70's, everyone was listening to a radio,
pretty much all the time. On their shoulder, on their desk, at the bus
stop...always radios in sight and to be heard. Because their defense
mobilizations went out on the radio, and people had to get that call-up notice
quickly.
 Now? It's very different. The Israeli's installed cellular phones much faster
than the US did. They chose cellular (in the 60's, simply getting a landline
installed there was a game) because it is MORE ROBUST than landlines. One
terrorist can take down one tower--but with lnadlines, one exchange building
takes out a much larger area. Same thing here.
 And, cellular was cheaper to deploy. We're seeing the same thing in China now,
building the world's largest telephone system in one of the lowest-tech nations,
and using cellular because it is the most effective way to do it.
 Israeli also managed to provide cellular service for about 6c a minute while
the rate in the US was still 60c per minute, go figure. And they placed
reverse-calling (emergency alerts) well before the US did.
 The concept of reverse-911 over cell systems, using the data channel, has been
tested. It works. Very nicely.

<<For example, the AM and FM broadcast
radio stations are a pretty good mass announcement system.>>
 They used to be, they are not anymore. Consider the case of a recent (chlorine
gas?) railroad tanker spill, I think it was last year in the midwest or central
states. It was widely publicized, because the local authorities wanted to
broadcast the evacuation order on five local AM radio stations. Except, it turns
out that all five stations were under the remote control of Clear Channel
Communications, Inc., those nice folks in Texas(?) that have absorbed some
incredible number of local stations and run them all by remote control and tape.
Ooops, the alert never got out.
 That's where AM and F radio are today, they are no longer longer resources and
can no longer be counted on.
AH, but what about TV? Well, what about it? Depending on who you listen to, one
third or one half of the US still listens to broadcast television, not cable.
And on 9/11 do you know what happened to some fifteen million people in the
great NYC area? That's right, we all saw the TV's go off the air, dead signal on
every VHF station except CBS, which incidentally hadn't completed their move to
the WTC tower yet. (CBS was due to shut down their Empire State Building site
and vacate the premises shortly.) In the urban canyons, that effectively means
"all broadcast television" would have gone black. UHF stations are so badly hit
by distortion, and so low in power, that most folks don't know they are out
there. IF there's anyone to staff them.

 Remember the Clear Channel Stations? Fifty thousand watts at night to keep you
informed of Russian bombers? Yeah, that's history, along with the Conelrad
markers on the dial. "Broadcast" media of any kind just don't reach the US
public the way they used to. Central towers (like the WTC) make it very easy to
blackout an entire area, and remote control makes it damn hard to just "send a
car to the station".

<<so they do not ADD to
the comms problem when they are used in an emergency.>>
 What comms problem? The problem of overloaded cells and pagers? SMS messaging
happens with such a light load on the system, you'd never notice it. That the
systems can be overloaded on the voice channels, is a separate issue. that
everyone and his brother want to pick up a phone and clog the lines every time a
butterfly sneezes, that's something else again. But you're right...broadcast
media can't effect the comms problem--especially when they are off the air, or
on remote control. Ooopsie.

>So, quit making rude jokes about the unlicensed masses and
>try building a better world for all of us instead.
 So, when is the last time that anyone else wrote to their CongressCritter, or
made any other attempt, to ask for a better communications system in the US? I
know the only problem with cellular comms here is "private enterprise". We only
had the Bell System because it was a govenrment monopoly and cost was no object,
for better or worse. We're not going to see a robust comm system in the US again
(what's left of the Bells have been cutting back on backup power and such for 20
years now) until the damned gummint gets out the carrot and stick again, and
that's not going to happen without people asking for it. Heck, we still pay a
telephone excise tax that was designed to fund the Spanish American War! How
about, we apply *that* money to hardening the cellular system?

<<I'm sorry sir, but that was my intent.  To make people "think">>
 I'll graciously accept yours if you'll accept mine.<G>

<<to flood the existing comms networks so that each person gets
an individualized notification of something that can just as >>
 You may have misread the case. The notifications aren't individualized, they
all would say the same thing in any one area. But they are LOCALIZED by using
the towers, so instead of saying "Evacuate Washington DC" and leaving people
trying to figure out which way to go, each tower gets a specific message that
says "EVACUATE NORTH" or "EVACUATE SOUTH" as the best solution for that specific
area. That local information can be a lot more important than a general
broadcast.

 Note that the reverse-911 functions would not interfere with routine emcomm
systems, as you seem to expect. Nextel claims that their "special bit" will
allow service to special phones only, and the rest won't matter. But in any
case...there is no bandwidth problem on the data channel. They are sending SMS
messages, typically 128 or 256 bytes at the most, over equipment that routinely
handles MEGAbytes of traffic. Blip, it's gone and done.

<<I think the word "easily" is an enormous stretch and shows
a blindness to economic reality.>>
 No, the "easily" part is a technological comment. Changing a million light
bulbs may require funding--but it is an easy job, simply repeated a million
times. Economic reality? Please, even the Nooze comentators asked "What planet
is he on?" after the State of the Union address. What planet are *any* of them
on? Pardon me if I quote Kinky Freedman who calls the Republicans and Democrats
"One guy shaving looking at himself in the mirror." How much money have we
pissed away in Iraq, trying to force democracy down the throats of tribal
nepotists who probably would be happier and more stable without it?
 Funding? Any idea where how much money goes in that Spanish American War excise
tax? We're already paying it every month on our phone bills. And in my state, a
cell phone 911 surcharge...that has gone to the state general funds for many
years now, without a cent going to cellular 911 systems.

<<alerts which will each trigger the receipents to immediately
start worrying and sending his own 10 emails and
phone calls in response causing melt-down of the system.>>
 Who says the system needs to function after that alert? Why can't it lock out
the overload and enforce throttling? And, since that overload is going to happen
as soon as "the word gets out" no matter HOW it gets out...why don't we attend
to the issues of overload and throttling the users now, anyway? (See, you made
me think.)

<<But they didnt have millions of ... generated by unthinking computers>>
 Computers never have thinked. That's up to the programmers, and I suggest that
whether the issue you perceive is a real problem or not, the fact that it
concerns you means that we need to speak to the programmers and ensure the
problem does not, or will not, exist.





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