APCO-25 AND ENCRYPTION

[PJH]

ADP is basically a poor man's encyption tool, more than scannerland lockout.

Spending $350 per unit is a hell of a lot cheaper than $700 per unit for the secure hardware. In addition to just the hardware chip, you also need a nice and expensive Keyloader(s) and cable(s) which don't come cheap.

When you are looking a large fleet of radio's, that a LOT of money that can be spent elsewhere. In dealing with local/state agencies you not dealing with classified information requiring Type 4 encyption.

As an example of cost differences, lets take my good old CSP example.

CSP has approximetly 1300 mobiles and 1300 portables in the field (actually more, don't remember the number).

If they wanted ADP encyption, at $350 each you are looking at $910,000. For say, DES-OFB that number goes up to $1,820,000. Neither number takes into account shop time and programming charges etc. This is also just for the field units, and not infrastructure if changes/upgrades are needed.

This is also a reason why you now see many smaller agencies with encyption and larger agencies without fleetwide encyption. Costs add's up. It cost me just over 4K each for XTL5000's with just DVP-XL, IMBE and display ID. Back in 1996 if we did our planned upgrade then, the Astro Spectra's would have cost us around $2,000 for the same thing.

 

[Karl-NVW]

If you go all the way back and read the first post again, you'll see that this version includes over-the-air rekeying of radios. System managers no longer need to physically touch the radio to change its encryption key. Hidden detail: If your radio is not affiliated on the system with an ID registered for encryption, it will never get the key updates.

 

[Karl-NVW]

If you go all the way back and read the first post again, you'll see that this version includes over-the-air rekeying of radios. System managers no longer need to physically touch the radio to change its encryption key. Hidden detail: If your radio is not affiliated on the system with an ID registered for encryption, it will never get the key updates.

 

[Glockorola]

Shawn, I believe the essential point of your question was not the nuance of OTAR, but rather the more generalized concern of encryption, and its potential effects on the scanner hobby.

We are currently in the era of increasingly widespread conversion of systems from the old 1950's era analog FM mode, to the more technologically current mode of digital. Although this changeout/upgrade from analog FM to digital is not moving nearly as swiftly as what we experienced in cellular, it is nevertheless occuuring. The really big cities are first to go, with smaller cities to follow, and then rural.

One can argue as to how long (or short) this conversion process will be. But, two things are for certain. The conversion to digital is happening, and it cannot be stopped.

Digital is necessary in order to achieve the necessary spectrum efficiencies required, as we have more and more users, and data intensive needs. This is just the reality of the situation, no matter how much one waxes nostalgic for the old analog FM mode.

Once a system is converted to digital, encryption is inevitable (not necessariuly at the get go, but at some future point). Adding encryption on a P25 system is reasonably straight forward, it does not degrade voice quality, and it is reasonably affordable (depending upon what was negotiated in the original equipment contract).

Sorry to say, but P25 with encryption (such as DES-OFB and/or AES) spells the death of scanners. It's just a question of time. This will happen, and No, you can't crack AES.

 

[PJH]

Any radio that is used in an OTAR system and takes advantange of OTAR does need to be loaded with a key at least once. This is called a shadow key, and that key allows the OTAR to work.

Should the radio go out for service, or if something quirks in the radio, you will need to load the shadow key, but its not going to be "in the shop" as often as any other radio to be physically loaded.

 

[SMbaugh]

I have a question concerning why when monitoring the new digital system in georgia here why sometimes a channel is keyed but no sound. Any idea what is causing this?

 

[crayon]

I have a question concerning why when monitoring the new digital system in georgia here why sometimes a channel is keyed but no sound. Any idea what is causing this?

You would most likey be best served if you started a new thread in the Georgia with this question.

The reason is because, someone who might know the answer, but does not want to talk about APCO25 stuff, would never see your question.