1) Project 25 a.k.a "P25" long predated Katrina. P25 is a (supposedly) open-standard "design-by-committee" digital mobile radio standard still incomplete after 25 years of effort.
2) An incredible amount of mis-information about P25 floats around among non-technical managers, politicians and government officials that keep repeating the post-911/post-Katrina mantra of "interoperability". The most egregious lack-of-understanding is that somehow merely owning and operating a "P25-compatible" network will "automagically" make you "interoperable" with other agencies. They fail to understand that P25 only defines a transmission protocol. P25-format transmission can be used on any of 4 or 5 different frequency bands from 30 MHz to over 900 MHz. Most radios and antenna systems only operate on one of these bands. The 30,000+ public-safety entities (federal, state, county and local) in the U.S. are scattered across all of of these bands. Or that IF several agencies that, by luck, do operate in the same frequency band show up at a disaster, that they still won't be able to talk to each other until considerable software tweaking and radio re-programming is done to make the digital addressing of various groups' radios match, in a manner somewhat similar to making LAN subnets mesh. (Unless of course, mutual-aid common shared channels are agreed upon in advance. This is common in adjacent jurisdictions such neighboring counties, or city police-vs-county sheriff in a given county, or counties-vs-state-patrol in a given state. However it all falls apart in scenarios like Katrina where diverse public safety groups from several states away show up to help.)
3) In fact, a brand-new P25 statewide public safety network had been turned on in Louisiana only months before Katrina, but failed massively due to the ravenous power demands of the complex P25 base-station and network-controller infrastructure. The modest power demands of classic "dumb" analog two-way radio base stations (10s of watts/channel on standby/hundreds of watts on transmit) can be backed up by battery banks at remote sites for days or even weeks at a time, possibly supplemented by solar or wind power.. The massive power demands of P25 systems with dozens (or even hundreds) of racks of power-hogging computer controllers, routers, servers and always-on-and-transmitting control-channel transmitters at each site means a continuous standby drain of 10's OF KILOWATTS. Typical battery backups can only provide a few minutes run time with this kind of drain, until fossil-fueled generators can (hopefully) start up. Typically the on-site fuel supply (usually diesel or propane) is good for 72 hours or so. However, the extensive flooding and general chaos made it impossible for fuel tankers to get to the sites for the first week or so. One-by-one the sites just ran out of fuel and shut down.
4) The sorry history of P25 in (more or less brief):
Over two decades ago, digital systems first started being proposed as a replacement for 50+ years of analog FM radio in commercial & public-safety mobile communications. Numerous proprietary digital protocols were pitched by manufacturers and basically went nowhere because each protocol was available from only a single manufacturer, eager to lock-in customers like police and fire departments to a single supplier for the life of the system.
Project 25 was undertaken by APCO (Associated Public Safety Communications Officials -- essentially the police and fire radio lobby) to define an open digital comms standard beholden to no one manufacturer.. It was grossly complex, as the result of being the typical design-by-committee responding to an endless stream of "It would be really nice if it could do...." requests from APCO members. Thousands and thousands of pages of documentation was issued. It not only covered the actual over-the-air data format for simplex, repeater and trunked radio systems down to the individual bits, but also d
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1) Project 25 a.k.a "P25" long predated Katrina. P25 is a (supposedly) open-standard "design-by-committee" digital mobile radio standard still incomplete after 25 years of effort.
2) An incredible amount of mis-information about P25 floats around among non-technical managers, politicians and government officials that keep repeating the post-911/post-Katrina mantra of "interoperability". The most egregious lack-of-understanding is that somehow merely owning and operating a "P25-compatible" network will "automagically" make you "interoperable" with other agencies. They fail to understand that P25 only defines a transmission protocol. P25-format transmission can be used on any of 4 or 5 different frequency bands from 30 MHz to over 900 MHz. Most radios and antenna systems only operate on one of these bands. The 30,000+ public-safety entities (federal, state, county and local) in the U.S. are scattered across all of of these bands. Or that IF several agencies that, by luck, do operate in the same frequency band show up at a disaster, that they still won't be able to talk to each other until considerable software tweaking and radio re-programming is done to make the digital addressing of various groups' radios match, in a manner somewhat similar to making LAN subnets mesh. (Unless of course, mutual-aid common shared channels are agreed upon in advance. This is common in adjacent jurisdictions such neighboring counties, or city police-vs-county sheriff in a given county, or counties-vs-state-patrol in a given state. However it all falls apart in scenarios like Katrina where diverse public safety groups from several states away show up to help.)
3) In fact, a brand-new P25 statewide public safety network had been turned on in Louisiana only months before Katrina, but failed massively due to the ravenous power demands of the complex P25 base-station and network-controller infrastructure. The modest power demands of classic "dumb" analog two-way radio base stations (10s of watts/channel on standby/hundreds of watts on transmit) can be backed up by battery banks at remote sites for days or even weeks at a time, possibly supplemented by solar or wind power.. The massive power demands of P25 systems with dozens (or even hundreds) of racks of power-hogging computer controllers, routers, servers and always-on-and-transmitting control-channel transmitters at each site means a continuous standby drain of 10's OF KILOWATTS. Typical battery backups can only provide a few minutes run time with this kind of drain, until fossil-fueled generators can (hopefully) start up. Typically the on-site fuel supply (usually diesel or propane) is good for 72 hours or so. However, the extensive flooding and general chaos made it impossible for fuel tankers to get to the sites for the first week or so. One-by-one the sites just ran out of fuel and shut down.
4) The sorry history of P25 in (more or less brief) :
...." requests from APCO members. Thousands and thousands of pages of documentation was issued. It not only covered the actual over-the-air data format for simplex, repeater and trunked radio systems down to the individual bits, but also d
Over two decades ago, digital systems first started being proposed as a replacement for 50+ years of analog FM radio in commercial & public-safety mobile communications. Numerous proprietary digital protocols were pitched by manufacturers and basically went nowhere because each protocol was available from only a single manufacturer, eager to lock-in customers like police and fire departments to a single supplier for the life of the system.
Project 25 was undertaken by APCO (Associated Public Safety Communications Officials -- essentially the police and fire radio lobby) to define an open digital comms standard beholden to no one manufacturer.. It was grossly complex, as the result of being the typical design-by-committee responding to an endless stream of "It would be really nice if it could do