Sound Off with Scott Tschetter of Eastern Communications
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Sound Off with Scott Tschetter of Eastern Communications
What is the biggest challenge you see in the industry today?
“There are a lot of customers that are … making a big investment and buying a digital, standards-based P25 system, and they’re doing it for all the right reasons—interoperability and compatibility with multiple manufacturers’ equipment. But then they’re falling for the trap of putting proprietary encryption on their talk groups, because it’s basically free—it’s less than $10 per radio, so they think that’s really helping them.
“But, by adding that $10 feature so that the guys on the scanners can’t listen to them, they’ve taken an entire standards-based system and made it into a proprietary system. All of a sudden, they’re not interoperable with their neighbors, they’re not compatible with multiple vendors, and everything that SAFECOM has tried to accomplish [for interoperability] is negated by proprietary encryption or a proprietary protocol … that’s not compatible with P25 Phase 2.”
Can you give us a specific example of this?
“The encryption for P25 is AES, and the standard also allows for DES, for backward-compatibility. DES and AES are both standard encryption algorithms—all the major manufacturers support that, and that’s what the standard allows for. The proprietary encryption that’s out there is called ADP. It’s 40-bit, as opposed to 256-bit for AES, so it’s very lightweight encryption, it’s proprietary, and it’s not part of the P25 standard.
“That’s a challenge for a dealer who has a customer who issues a press release and tells their town council that they’re putting in a standards-based system, so they can have interoperability, compatibility and competition. But, through their practice of using proprietary encryption, now they’re really locking out all of the dealers that don’t represent the ADP-capable radios.
“Some customers want encryption for their own reasons, and ADP is attractive, because Motorola sells it for $6 per radio or $7 per radio. AES is typically $500 per radio, so there’s a big price difference—it’s not cheap.
“If you buy a new radio from EF Johnson or Harris, they’ll give you single-key DES for free. It’s 56-bit encryption, which is significantly better than 40-bit [ADP]. But even more importantly, at least it’s a standards-based encryption that’s compliant with the P25 standard, so now you can maintain compatibility and interoperability between other jurisdictions.
“Now, it’s single-key [technology]; you’re not going to be rotating keys. If you want to be rotating keys and having over-the-air rekeying, then you’re going to need to spend the big money and buy AES. But, if you just want some basic encryption to have some level of privacy, [DES] accomplishes that—and it’s free.”