How would satellite communications have helped in the World Trade Center mess? For that matter, how would municipal wireless have helped?
Satellite comm certainly has its place. Many of the COW's (Cell sites on Wheels) use satellite for their backhaul. CA OES and FEMA both have satellite comm systems. However, these tend to be concentrated at the emergency centers. Once communications breaks down between the PSAP's (public safety answering points), satellite becomes less than useful.
True. NVIS HF does handle medium range communications that is farther than can be done on VHF/UHF, but not so far that one ends up out of state. As for capacity, maybe 300 baud via HF using Pactor 3 on a good day.
I'm not familiar with what communications problems were caused by WTC so I can't answer.
In general, if a set of people are issued satcom radios they can communicate with one another in the absence of any local infrastructure surviving. From what I hear, this would have helped during Katrina if at least some responders had this capability, because there were many reports of responders (including FEMA) on the site unable to reach their offices.
Excellent plan.
So, you're saying FEMA individuals in the field don't have satcom radios. IMO at least some fraction of them should. Unless things have changed, National Guard units do. (It would be sad if they ditched this capability, figuring there'd always be cellular capacity.)
Yes. I remember looking at near-vertical HF years ago. The application was shore to just offshore. I don't recall what the data rate limits were. It was a second choice to satcom; with all satcom channels assigned, there were still people left over trying to use HF.
Exactly. That's not easy to do on an ad-hoc basis. As field units arrive from all across the country, they usually bring their own communications with them. Sometimes, it doesn't quite work as when a search and rescue team from California arrived in Florida for hurricane relief and found itself talking on the local sheriff's channel. In theory, each arriving agency contributes a radio to the interoperability box. The box acts as an IP switchboard to deal with traffic between agencies. Incidentally, there's no attempt to turn it into a giant party line, where everyone hears everyone else. It's strictly on demand which puts the load on whomever is "operating" the switch, which is not an easy exercise.
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They vary from 8 to about 32 ports. Any more would be a mess. There are also virtual IP circuits (VPN) to add to the puzzle.
Not exactly. The Cisco proposal (it's not a product yet) is to do everything the interoperability boxes do and then some. What Cisco brings to the table is decent VoIP solutions and internet intefaces. Everything else has already been worked out by the other vendors.
I don't understand the question. There's no beef. What's missing is a sane and sober method of uniform inter-agency communications that does NOT require a kludge, band-air, or technical abomination to accomplish. In addition, the general lack of reliability of infrastructure based communications (cellular, SMR, trunking) keeps pointing to plain old simplex FM as the most reliable communications method in case of a real disaster.
Right. I was once driving in Smog Angeles when the Malibu hills were on fire. I tuned to the local fire channels and only heard a little traffic. However, when I ended up on Clamars (inter-agency communications channel), the entire world was trying to talk on top of each other. Everyone was on the two (now 7) channels because those were the only channels that all the fire fighters radios had in common.
They would be thrilled if they could just get to an inter-agency dispatch center via radio instead of directly to the firefighters.
Agreed. My solution would be to REQUIRE a "talk around" channel in all such complex infrastructure based repeater systems. The ability to work simplex with the infrastructure goes away would have been a big help.
No. Agencies hang onto their radios well past the point where they should have been recycled. My main complaint about Cisco and friends is the introduction of excessive complexity of dubious value. However, this may not be the consensus among emergency managers, who seem to value features and functions (while they're working).
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