Analog and Digital Combination

[K2NEC]

Here's the way I see it.

Kinnelon PD use a 6 site, IPSC, UHF, system with Gen 1 XPR6550s. They have used this system for a few years now and they are happy with their system. It gives them coverage around the entire town and for the most part, it is good when it works well. Sometimes officers have to manually switch sites because they are just out of range of the site they automatically connected to. I see that as a training thing not a radio problem. Now here's where we get to the problems. When we had the storm one of the sites went out and PD lost all communications in that area. Then there was a medical call there and PD on scene couldn't be reached and the ambo had no coverage in that area on their frequency. At one point, none of the sites were connected together and every site was like it's own repeater. Well now no one can call dispatch unless they are on the same site as dispatch.

Bloomingdale PD use a 3 site, IPSC, UHF, system with Gen 2 XPR3500es. They just switched to their IPSC system in the last 6 months and I don't think they are too happy with it. They seem to have coverage issues in town and one of the sites always seems to have a problem with it. There are times where I can hear units on 1 site but dead silent on another. Almost like the site loses connection somehow and just goes down. Radio shop came and "fixed it" but the problem persists AFAIK. They also reported that they didn't have coverage inside a structure right across the street from the site. This is probably because they were right under the site and the antenna was 35 feet above their heads. The radio company came out, did some tests, and probably told them there isn't much they can do about it.

IMHO the BIGGEST problem with IPSC and public safety is the time it takes for the radio to connect to a site. When you power the radio on, it immediately starts looking for a site. Depending on the beacon of the sites, it could be 5 seconds then it connects or it could be 30 seconds and then it connects. Imagine being an officer taking fire and needing to wait 30 seconds to call for backup. But wait... it gets better. When the radio goes out of range of a site the radio needs to not get signal for 1 MINUTE before it says "I'm out of range of a site, maybe I should look for another one" and imagine that same radio now also has to wait 30 seconds before it connects to a different site. That's 1 minute and 30 seconds between the radio going out of range and connecting to a new, closer site. For public safety, this is unacceptable. Especially considering that officers are constantly driving and moving and changing sites. Let's give an example, An officer is in a pursuit and is in the middle of a site change. Suddenly the car stops and the suspect runs. The radio is changing a site and the officer goes to key up to give his location. *BONK* Now what? He has to wait for the radio to pick a site and connect to it or manually look at his radio and switch to the site that he thinks is closest to him.

This also partly has to do with what the radio shops program the repeaters for. They could do a beacon every 5 seconds or every minute. Too fast and the radios might spaz out between sites, too slow and you are going to be waiting for a while to be reconnecting to a site. Kinnelon have every 10 seconds which IMHO is reasonable. Bloomingdale on the other hand, 30 seconds.

Whether a department use DMR or P25 or analog, there needs to be training with radios. Officers can't just be handed a radio and expected to know how to use it. I have seen officers struggle with why their radio wasn't connecting and if they were told "this is what happens" they would have an understanding. Going from an analog repeater to a 3 site DMR system is a big change. Going from analog to a county wide P25 trunking system is a big change.

won't even discuss how running encryption results in degradation in audio quality, whereas P25 encryption doesn't.

Sir I respectfully disagree

 

[MTS2000des]

Are you comparing AES-256 to AES-256? I assure you, there is no noticeable degradation when using 256 on Mototrbo. Enhanced Encryption is barely noticeable. I can hear it a little bit, but most people cannot.

AES-256 isn't widely available to MSI customers in the USA. They instead offer welfare encryption known as "enhanced privacy" and yes, it is documented to degrade DAQ.

When we had the storm one of the sites went out and PD lost all communications in that area. Then there was a medical call there and PD on scene couldn't be reached and the ambo had no coverage in that area on their frequency. At one point, none of the sites were connected together and every site was like it's own repeater. Well now no one can call dispatch unless they are on the same site as dispatch.

IMHO the BIGGEST problem with IPSC and public safety is the time it takes for the radio to connect to a site. When you power the radio on, it immediately starts looking for a site. Depending on the beacon of the sites, it could be 5 seconds then it connects or it could be 30 seconds and then it connects. Imagine being an officer taking fire and needing to wait 30 seconds to call for backup. But wait... it gets better. When the radio goes out of range of a site the radio needs to not get signal for 1 MINUTE before it says "I'm out of range of a site, maybe I should look for another one" and imagine that same radio now also has to wait 30 seconds before it connects to a different site. That's 1 minute and 30 seconds between the radio going out of range and connecting to a new, closer site. For public safety, this is unacceptable. Especially considering that officers are constantly driving and moving and changing sites. Let's give an example, An officer is in a pursuit and is in the middle of a site change. Suddenly the car stops and the suspect runs. The radio is changing a site and the officer goes to key up to give his location. *BONK* Now what? He has to wait for the radio to pick a site and connect to it or manually look at his radio and switch to the site that he thinks is closest to him.

and this just demonstrates why this type of system isn't prime for public safety use. You illustrated my point very well. A user has NO IDEA that the network is in a degraded state and thinks all is well and has no indication, even a basic alert tone/display indication of a link failure. P25 trunking systems do. In P25 trunking, site trunking is akin to a backhaul/link failure to the core and keeps trunking going at the local site level. USER IS NOTIFIED (endlessly at that).

FAILSOFT is a total loss of site controller and reverts to conventional repeater operation. USER IS NOTIFIED AND AWARE.

Does DMR support this type of operation? Not on our IPSC system. As the example above shows, when a site drops, it's just gone. Link back to your dispatch point goes TU? Too bad, so sad. Just reach for your cellphone...

Last week we just upgraded our core to the latest release and had two small instances of site trunking. Users knew immediately as the words SITE TRUNKING flashed on their subscribers, along with a periodic tone, alerting them to the state of the network. There isn't some hodgepodge of school bus grade repeaters beaconing and subscribers engaged in what essentially amounts to glorified conventional voting scan to affiliate and receive talk group traffic. So many points of failure waiting to happen this isn't even funny.

as I said, DMR is a great drop in replacement for analog SMR/closed systems for use by non-critical applications. Your local mall security, building management, taxi service, transportation, manufacturing facility will benefit well from such a system.

Wide area public safety trunking applications are best suited to networks and systems designed for that purpose. P25 isn't cheap, but it is what it is.

 

[APX8000]

There is a site on the County P25 right in Kinnelon....what coverage does that give up that way in addition to the other simulcast sites on the trunked system is that area ? I rarely make it up to that side of Morris.

Spectrum sales guy talks to Chief who has no radio background and says how he can have all these sites, digital clarity, and for a fraction of the price. The majority of these administrators really don’t have a clue as to how the infrastructure is designed, programmed or how a subscriber behaves. How many agencies that have their own dispatch in Morris are on the trunked system...ZERO (except for mutual aid). It was the same in Bergen until recently. So where is he going to go ? Easy sale for a clueless Chief and a good salesman.

I’ll back you 100 percent that I don’t like Public Safety on IPSC. If they want DMR, and they can’t get the coverage they want with one site (like Pequannock and again, not big on PD on DMR), then go to something else. I’m sure they could have turned their analog into a nice P25 conventional repeater, put up a few receiver sites to improve talk-in and called it a day.

 

[K2NEC]

Yea I'll admit IPSC for public safety is a mistake. But as you said, a clueless chief and a good salesman will surely make it happen. But at the same time the cost is also a factor. Small town USA can't necessarily pay $25,000 on a new radio system if they could have one for $10,000.

If I was in charge of radios for any of the local towns I would have picked DMR too because everyone around here uses DMR. Don't be like Wayne trapped in their bubble, where everyone around uses something besides UHF P25 PI.

There is 1 BIG reason local towns are going with XPR's and DMR: Interoperability.
They see it as "this town has DMR and this town has DMR so let's go DMR because we will be able to talk to them"

People argue that DMR isn't meant for public safety but I will argue that there is nothing wrong with DMR for public safety. There is something wrong with IPSC for public safety. Pequannock has 1 repeater and they get very good coverage with it. They also don't have nearly as many problems as the towns mentioned above. They also use DMR for fireground but that's a whole different conversation lol

 

[alcahuete]

AES-256 isn't widely available to MSI customers in the USA. They instead offer welfare encryption known as "enhanced privacy" and yes, it is documented to degrade DAQ.

Well-aware of both, but that's an apples to oranges comparison. It is not that Mototrbo is somehow inherently bad, it's that they intentionally cripple it to "encourage" people to go with P25.

Small town USA can't necessarily pay $25,000 on a new radio system if they could have one for $10,000.

And this is where Motorola is going to shoot themselves in the foot, only they're too stupid to realize it. Mother /\/\ might not offer AES-256 readily, but Kenwood certainly does. And when it's DMR or nothing, these smaller towns are going to give /\/\ the big middle finger.

 

[Cameron314]

Most of these "system" owners aren't trying to figure out how they can replace their single analog repeater with a multi site P25 or a CapMax system but rather if they can replace their 25 year old repeater and maybe get an something a little better. Maybe others are seeing something different but I'm not seeing big CapMax public safety systems, the DMR users seem to be more rural with single repeater or IPSC repeater networks. To compair that to a P25 trunked system is a bit much and is a bit of a false choice.

 

[K2NEC]

And when it's DMR or nothing, these smaller towns are going to give /\/\ the big middle finger.

It doesnt even have to do with DMR. I know a department that wanted a UHF and VHF mobile in their vehicles without having to get 2 radios and they didnt want to spend a fortune on the apx8500. What did they do instead? Kenwood NX.

Most of these "system" owners aren't trying to figure out how they can replace their single analog repeater with a multi site P25 or a CapMax system but rather if they can replace their 25 year old repeater and maybe get an something a little better. Maybe others are seeing something different but I'm not seeing big CapMax public safety systems, the DMR users seem to be more rural with single repeater or IPSC repeater networks. To compair that to a P25 trunked system is a bit much and is a bit of a false choice.

You are definitely right. And I personally have yet to see a dmr trunking system for public safety

 

[MTS2000des]

Most of these "system" owners aren't trying to figure out how they can replace their single analog repeater with a multi site P25 or a CapMax system but rather if they can replace their 25 year old repeater and maybe get an something a little better. Maybe others are seeing something different but I'm not seeing big CapMax public safety systems, the DMR users seem to be more rural with single repeater or IPSC repeater networks. To compair that to a P25 trunked system is a bit much and is a bit of a false choice.

Not when agencies are sold the "P25 trunked" experience when they aren't getting it. In my area, this has happened in three different places. All three bought IPSC CAP Plus and told "yeah it's just like those guys P25 system" when in fact, it isn't.
Guess what, all three are in the process of replacing these less than 5-8 year old deployments with...wait for it...Astro 25 systems.

 

[mmckenna]

Sure would be nice if Motorola would take a cue from Kenwood (that'll never happen) and produce a radio that does P25 and DMR.

Once again, Motorola Marketing getting in the way.
But there's nothing to stop these agencies from buying the NX-5000 line of radios.

 

[GTR8000]

But there's nothing to stop these agencies from buying the NX-5000 line of radios.

Does the NX series still lack the RC4 (aka ADP or ARC4) algo? Last time I checked, they were DES or AES only. The EFJ/Kenwood Viking line has that algo, but of course it's P25 only. So if an agency is using ADP on a P25 system, then the NX series lack of that algo would stop them from buying those radios.

 

[mmckenna]

Does the NX series still lack the RC4 (aka ADP or ARC4) algo? Last time I checked, they were DES or AES only. The EFJ/Kenwood Viking line has that algo, but of course it's P25 only. So if an agency is using ADP on a P25 system, then the NX series lack of that algo would stop them from buying those radios.

Yes, they have RC4. It's costs a whopping $40 list. So easy to knock that down to $28/radio.

I have seen instances where a Chief will only buy "certain" brands of radios, and no aMount of logic will get them past that.

 

[mmckenna]

I'd need to do some more digging, but it's possible that ARC4 is only available for DMR, and not P25.

Motorola and their damn "free" ADP encryption…..

 

[MTS2000des]

All the EFJ VP5430s on our system came with ARC-4, and we added AES-256. IIRC, the dealer wanted to sell them NX series instead but the hangup was availability of ARC-4/ADP which is used by some mutual aid partners. The VP's support it under the Armada firmware but not on the NX series with NX firmware?

 

[mmckenna]

All the EFJ VP5430s on our system came with ARC-4, and we added AES-256. IIRC, the dealer wanted to sell them NX series instead but the hangup was availability of ARC-4/ADP which is used by some mutual aid partners. The VP's support it under the Armada firmware but not on the NX series with NX firmware?

My understanding matches yours on that subject.
EF J = Armada = Analog/P25/SmartNet/SmartZone. P25 + ARC4, AES/DES
Kenwood = KPG-Pain-in-the-arse = Analog/P25/DMR/NXDN. AES/DES, ARC4 on DMR only.

The whole Kenwood/EFJ thing is annoying. I'm sure some of it has to do with the SmartNet/SmartZone licensing to EFJ only.

 

[DanRollman]

Not when agencies are sold the "P25 trunked" experience when they aren't getting it. In my area, this has happened in three different places. All three bought IPSC CAP Plus and told "yeah it's just like those guys P25 system" when in fact, it isn't.
Guess what, all three are in the process of replacing these less than 5-8 year old deployments with...wait for it...Astro 25 systems.

Let me guess: Habersham, Douglas and Polk Counties? Or are there actually more than 3?