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2006-02-18

[Preparedness] Radio frequencies useless if they don't work

The next time you hear some politico blithering about 'spectrum' and 'compatability' for emergency responder radio, you'll understand how clueless they are if you've read this article. Don't coast on these excepts; there's a lot more meat in the entire article..
There are many lessons to be learned from how emergency communications performed, or failed to perform, in the wake of Katrina. The debate is burdened by a weighty status quo, bureaucratic politics, and the inescapable fact that emergency response most often is a local function, divided up among more than 60,000 state, county and city jurisdictions nationwide.
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But no one perfect frequency exists for all emergency communications; firefighters prefer the brick-and-concrete-penetrating abilities of lower frequencies, for example. No single frequency band can meet the public safety demand.
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Katrina, however, drives concerns about emergency communications down to an even more basic level. The hard truth is that interoperability is meaningless without intact communications systems. A fair amount of emergency planning simply assumes that communications infrastructure - towers, microwave relays and electric or generator power - will mostly continue to exist and function.
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Every type of infrastructure has a failure point, and this fact applies even more to emergency communications infrastructure that is owned and operated almost exclusively by financially strapped cities and counties. When bits of infrastructure are knocked out, ad hoc networks should just snap into place, say proponents of Internet protocol communications. They want public safety communications to be plug and play.
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IP's basic premise is that infrastructure is vulnerable, says Matt Walton, chairman of the Emergency Interoperability Consortium, a pubic-private effort to create public safety data-sharing standards. It was developed by the government to withstand a nuclear attack. Internet protocol converts data, including voice, into discrete packets and spontaneously routes them across a network. That means it doesn't depend on a pre-established pattern to complete the circuit from sender to user. If some network infrastructure elements are disabled, then Internet protocol will route around them. "If you're going to lose everything, the first thing that's going to come back up is the Internet" because of its dynamic routing capability, Walton adds. He points to Katrina as proof of IP's ruggedness. In New Orleans, "the only system that was up for, I think it was the first five days," he says, was the Hyatt's Internet connection. Even in areas where the infrastructure was completely wiped out, the Katrina experience showed that rapidly deployable satellite-powered Internet can plug gaps.
And because data packets don't care about which frequency a voice signal originated from, Internet protocol creates interoperability, its champions say. Hand-held devices still transmit in their specific frequencies back and forth to radio towers, but once signals are converted into packets, they can be delivered to any frequency and any device. Whatever remaining bits of spectrum infrastructure still exist become part of an Internet-based network. Devices not normally included - cell phones or Voice over Internet Protocol-enabled laptops - can become part of it, too.
"When you're using Internet protocol, you don't replace all of the end user devices; you use exactly what you have today," Wethington says.