----- Original Message -----
Sent: Sunday, September 11, 2005 1:37
PM
Subject: RE: [Asterisk-Users] civil
emergency comms: Asterisk + HAM
Time and time again, emergency action drills take place
in cities to target where their weaknesses are in "crisis" handling.
Usually they involve planes crashing or explosions (mock of course).
Obviously they were never prepared for this sort of disaster in their recovery
plan. I've participated in a few ARES/RACES drills and have to say that
much could be done to improve upon the "HAM"
infrastructure.
Most of the time, communications is coordinated through 1
repeater system. When this repeater goes down, of course people would
switch comms to another but in a case like this, where all the repeater
systems go down except for maybe one, there needs to be a better
plan.
In Amateur Satellite Service, these orbiting "Repeaters"
employ a system called RUDAK where a chunk of spectrum is repeated.
Obviously this isn't feasible in terrestrial repeaters but they do have
the ability to turn off radios and switch bands at will depending on operating
conditions. With software controlled radio and Asterisk, the repeater
system could be made to be more resilient to disaster by linking to other
repeater systems via radio where it could connect outward.
If you figure the overhead of a repeater's transmitter
and receiver plus the controller, replaceing the controller with an asterisk
based unit (integration) would make more sense as it would give the repeater
system much more capabilities in the same footprint and power.
Additionally, these repeater systems are located on hilltops with other radio
systems so they should have emergency power available (if you've ever been to
a hilltop repeater site, you'll know what I mean).
I think the biggest thing that hurts ham radio's ability
to react to a crisis is the lack of equipment and operators. Most of the
traffic we pass is "Health and Welfare" with "Logistics" being the second to
it. What defeats this is that in a disaster where local/high band long
haul capabilities are diminished, is simply the one repeater that is
functional because everything is squeezed onto one VHF/UHF
repeater.
Where I could see thing being improved?
Installation of 802.11b/g WLAN under Part 97. It would allow for more
users into the system, there are less hardware and power components and allows
the system to be dynamically configured. Asterisk could play a huge role
then as it's made for IP based traffic and could re-route in a split
second.
-Don
The two best forms of communications in a real disaster and one
always has been is #1 Ham radio. and #2 satellite telephone. Ham radio is
global and has proven time and time again to be the most reliable when the
infrastructer has been damaged. The U.S government is the biggest user
of satellite telephones which is also becoming a valuable tool again when the
communications infrastructure is down. It would be nice If Asterisk
could be used but in this case but it's useless. People are displaced
and most of the communications infrastructure for the city is unusable.
I don't mean all of the telco's systems. It's the flood that wiped out
most home and business systems. For us, The best thing that a provider
can do is to have redundant servers in different cities. This should
remind us all how fragile our lives are.
Chris Travers
wrote:
Mark
Phillips wrote:
Hold on here folks,
I'm guessing that the
original poster of this thread isn't a member of his local RAyNet team.
Whilst I don't profess to be an expert at this I have been doing
emergency radio for quite some time and have seen service at the Lockerbie
bombing, Docklands bomb, Ground Zero (I'm sure I'm a terrorist target
y'know - they seem to follow me everywhere) and soon I'll be in Louisiana.
In all of these events the KISS principle must and does prevail.
We need a system that is a simple and energy efficient as possible.
Building a network of * servers and Wi-Fi
links is all very well but how are you going to power them?
These are excellent points. I have a few
interesting suggestions here.... The first is that the only obstacle
to any sort of longer-range point to point line is merely power. This
is true whether you are talking HAM or fiberoptics. Note that if you
have the power, it would take disruption of the physical line to disrupt a
fiber line. Note that DirectNIC in New Orleans remained operational
without *any* downtime or loss of connectivity with the rest of the world.
The suggestion that I have is for various areas to have dedicated
civil emergency com units with strategic reserves of fuel (3-4 weeks worth),
battery backups, etc. These units would have links (fiber, microwave,
and/or satellite, better to pick 2 of 3) to areas outside expected disaster
zones. Asterisk could then run across these links. (Sattelite
links would best be POTS-type).
The point is to a disaster-tolerant
communications infrastructure which could then be used to to provide
additional communications services to the relief workers. With various
point to point wireless capabilities, it might be possible to use them to
provide cell service to relief workers etc through the installation of GSM
microcells (which could be brought in after the fact).
See where I
am going?
Generators require fuel which is always in
short supply and batteries die out quickly. Adding Ham Radio to the
picture doesn't really add much when you are trying to do something like a
* network. The radio gear just isn't designed to integrate with the *
server.
Ham radio is being used down in the Katrina affected area
with great results for both emergency and heath/welfare related traffic.
They are using both "phone" (that's when one talks in to the radio) and
data modes and can be heard all over the 75 and 40 meter bands here in the
US.
Power for most of these stations comes from batteries they
loot (with Police approval) from abandoned cars or a combo of solar and
batteries. Many stations are only hear on the air after dark so that they
can put as much sunlight into their batteries as possible.
Yes,
electricity is available in some places either all day or across the peak
hours (allowing the workmen to restore power to other areas).
Yes,
there are radio to phone interconnects but these really are a single phone
to a single radio. Think of it as a cordless phone in that the radio user
can be anywhere within reach of the base station.
Such
technologies, whilst legal here in the US, may not be legal elsewhere.
When last at home (UK) I was not able to connect my radio to the phone
system by law (this may have changed recently - not been home for 8
years). Many countries have such restrictions and as we saw during the
Tsunami, rules don't get relaxed just because there's a panic on.
Without question a phone system would be much better than a radio
station. As such I'll be taking a portable * server I've built, all the IP
hard phones I can find and 5 DirectTV style Internet systems.
How do IP hardphones work with satellite
internet? I always thought people had real trouble getting them to
work at all.....
Best Wishes,
Chris Travers
Metatron
Tecnology Consulting
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