Why so much conventional (no-trunking) in NYC?

[Raccon]

The only training program you should need to operate a radio in the public safety field is the ON/OFF and PTT buttons. Anything more than that requires more effort than is needed to do your job.

I realize I am virtually alone in this opinion but I have said it since the beginning: trunking has no place in mission critical functions. There are too many links in the chain that can fail.

There are hundreds of trunked public safety systems around the world with different levels of resilience that work just fine; it might also just be your opinion that public safety requires voice only operation but all those systems, build with features that are based on the end-user requirements, prove you wrong.

 

[Raccon]

You are talking about 2 different worlds, the TETRA you have is mostly privately owned, not a common practice here in the U.S. YET. I don't believe that a private company should control the radio comms of Public Safety.

Not a common practice for TETRA either, the majority of TETRA networks in the PS market are government owned and operated.

TETRA has it's uses but in my opinion it hasn't grown up enough to compete with P-25 as a true Public Safety radio format.

Have you looked at the number of public safety TETRA networks worldwide, with some of them being nationwide systems? To say TETRA is not mature and can't compete with P25 as a PS radio format is uninformed and false.

The problem is actually that statements like these are very general but should be made in reference to the specific requirements of the US, where it is not a matter of maturity but rather an issue of standardization (TETRA was not designed to be directly interoparable with conventional/analog systems as P25 was, based on specific, US-driven requirements) and an issue of geography, i.e. for large coverage areas like those in the US P25 is better suited. TETRA however works very well elsewhere, as proven by the many com./industr. and PS systems outside of the US.

TETRA is very infrastructure intense, meaning it needs a LOT of radios sites, more on the order of a cell system, and other than it is being unmonitorable, which China I'm sure wants due to it's draconian attitude towards it's public.

I am not sure what China has to do with this but many PS organizations seem to like encryption, regardless of the underlying technology. Judging by the many debates here in the forum that includes the US, too, and they don't use TETRA so much.

TETRA may have it's place in commercial and industrial communications, but I wouldn't want it for Public Safety.

Although TETRA was designed with commercial/industrial applications in mind it was also designed with PS needs in mind, providing countless PS-specific features and functions.

While I agree that it would be 'challenging' to sell TETRA to the PS market in the US (licensing issues aside) I strongly disagree that TETRA is not mature or not suitable for the PS market in general, in fact it's quite the opposite judging by the dozens if not hundreds of PS organizations around the world that use TETRA.

 

[radioman2001]

Just because TETRA is used in other places of the world doesn't make it a world standard, and better than P-25. Again it may work overseas, but in the U.S. P-25 is THE format, maturity aside and I don't think it is a mature P.S. format just a good commercial industrial format. Anything TETRA can do P-25 Phase II can do, and TETRA would also require a total rebuild of channel spacing in the U.S. since in it's present form it requires a channel spacing greater than what is the norm here in the U.S.
If you want to throw a monkey wrench in to radio system standards look what MOTOTRBO is trying to do. Make itself a standard when it is not, but a subset of an another standard.
TETRA may get a few industrial systems built here, but it will never make it here in the U.S. as a standard.
There is a need for P.S. radio systems to be backward compatable, TETRA cannot, therefore it will never be embraced by the Public Safety community. I equate it to the ACSB product that came out 30 years ago. Been there tried that.

 

[Raccon]

Just because TETRA is used in other places of the world doesn't make it a world standard, ...

I don't recall myself claiming it's a world standard but since you brought it up please take note that TETRA is an [open] standard which is being used world-wide, not just through building TETRA systems in many places of the world but also through non-European companies that design and manufacture TETRA products. That does make it - like it or not - a world standard.

From TETRAMOU:

Although the prime responsibility of ETSI is to develop standards for Europe, many of its standards are also adopted world-wide, as evidenced by the uptake of GSM, the first wireless technology standard to be developed by ETSI. Similarly, TETRA has already been deployed in many regions and nations outside Europe, resulting in TETRA becoming a truly global standard.

...and better than P-25.

Which I never claimed. Both systems have their pros and cons, sometimes P25 is more suitable, sometimes TETRA. But I take issue with your unsubstantiated claims that P25 is better because TETRA is less mature and more suited for com/ind use, both of which is incorrect.

Again it may work overseas, but in the U.S. P-25 is THE format, maturity aside and I don't think it is a mature P.S. format just a good commercial industrial format.

To "think" it is not mature and 'just a good commercial industrial format' is an opinion if you don't back it up with any facts and ignore the arguments given that show otherwise. Repeating that opinion doesn't make you right, regardless how often you do so.

Anything TETRA can do P-25 Phase II can do, and TETRA would also require a total rebuild of channel spacing in the U.S. since in it's present form it requires a channel spacing greater than what is the norm here in the U.S.
If you want to throw a monkey wrench in to radio system standards look what MOTOTRBO is trying to do. Make itself a standard when it is not, but a subset of an another standard.
TETRA may get a few industrial systems built here, but it will never make it here in the U.S. as a standard.
There is a need for P.S. radio systems to be backward compatable, TETRA cannot, therefore it will never be embraced by the Public Safety community.

If you read my response carefully you will notice that I agreed that P25 is better suited to the PS market in the US due to the specific requirements there, so I am not sure why you are trying to argue with me about that.

 

[PetervonB]

There are hundreds of trunked public safety systems around the world with different levels of resilience that work just fine; it might also just be your opinion that public safety requires voice only operation but all those systems, build with features that are based on the end-user requirements, prove you wrong.

There are also hundreds of public safety systems (primarily fire) that have found use of trunking (and repeaters as well) on the fireground to be extremely dangerous. And when you speak of digital systems, several major cities still use their old VHF analog portables on simplex on the fireground because of the problems inherent in the new P-25 digital systems. Others (perhaps they accidentally threw out their old radios) at least have insisted on digital simplex for fireground use.

Trunking is great when you expect to have a lot of users and few available frequencies. Trunking makes more efficient use of those frequencies. It is still subject to more misses and overloads than conventional repeater or simplex systems.

 

[william1]

Thanks everybody! The site I’m concerned with is at Kennedy Space Center (KSC.) Our trunked system has been shared with two neighboring Air Force bases, but we are about to be on our own. KSC alone is a couple of hundred square miles with relatively few buildings. Our usage would spike when we launched a Shuttle, otherwise, it is light. The task at hand is to compare the costs and features of a conventional repeater system with voting receivers and a trunked system. The person advocating for conventional pointed out that digital private line can allow multiple talkgroups to share a single repeater, with the annoyance of being blocked sometimes. KSC is far from the NYC example; we’re more like two little towns with a lot of land around them which hosts a huge festival once in a while. The advocates of trunking point-out that our customers have become accustomed to having plenty of talkgroups, and will resist being compacted back into fewer channels.

 

[55engine]

p25

what the new p25 for nyc idk know thay have one what the frq?

 

[Raccon]

There are also hundreds of public safety systems (primarily fire) that have found use of trunking (and repeaters as well) on the fireground to be extremely dangerous. And when you speak of digital systems, several major cities still use their old VHF analog portables on simplex on the fireground because of the problems inherent in the new P-25 digital systems.

P25 may be a digital system but digital systems are not all P25. As said digital seems to work well for the rest of the world, so perhaps the problem is not with digital systems in general but P25 ... ?

Trunking is great when you expect to have a lot of users and few available frequencies. Trunking makes more efficient use of those frequencies. It is still subject to more misses and overloads than conventional repeater or simplex systems.

Got any evidence to support that claim?

I would think that a properly designed and dimensioned system will not overload, so perhaps the problem is once again not with the (digital) technology but the particular systems that you have in mind.

 

[902]

There are hundreds of trunked public safety systems around the world with different levels of resilience that work just fine; it might also just be your opinion that public safety requires voice only operation but all those systems, build with features that are based on the end-user requirements, prove you wrong.

A well-engineered system is intuitive and takes much of the effort out of communication. The radio system is NOT meant to be a quiescent uitility, it is meant to be a utility which serves the users' needs under duress. It is incumbent on its designers to know and anticipate the needs of its users and facilitate each of those needs through building in the coverage, capacity, and functionality. IT IS NOT THE MISSION OF A RESPONDER TO WORK THE RADIO. The responder's mission is to devote their attention to: 1) their safety and survival; 2) the safety and survival of those around them; and 3) apply their knowledge, skills, and abilities to address the situation they are called to the scene for. Frank is correct, the radio needs to be as minimalist as possible. The responder has many, many other things to do than dick around with an unintuitive product, be it unintuitive by design, omission, or simply poorly-committed programming (the most problematic issue in my opinion). The product is there to serve their needs, not the other way around.

You touched upon another issue with respect to data in alluding to the value of data being greater than that of voice. Let's take that further to the concept of enhanced situational awareness. How much is too much? Can the vision of some here in the US (streaming video and metric data from everyone and everything on-scene to create a meta-model of the evolution) enhance situational awareness or will it impede it? Assuming this is indeed an enhancement, would direction from a synergy center remove the discretion of those who are actually there? Would this be a shift from discretionary ability to ministerial duty?

Perhaps the most valuable thing any manufacturer can do is stop making four or five figure nifties and toys, and get their behinds out into the street with the people who actually use the stuff to see how their technology can enhance their safety and performance.

 

[Raccon]

A well-engineered system is intuitive and takes much of the effort out of communication. The radio system is NOT meant to be a quiescent uitility, it is meant to be a utility which serves the users' needs under duress. It is incumbent on its designers to know and anticipate the needs of its users and facilitate each of those needs through building in the coverage, capacity, and functionality. IT IS NOT THE MISSION OF A RESPONDER TO WORK THE RADIO. The responder's mission is to devote their attention to: 1) their safety and survival; 2) the safety and survival of those around them; and 3) apply their knowledge, skills, and abilities to address the situation they are called to the scene for. Frank is correct, the radio needs to be as minimalist as possible. The responder has many, many other things to do than dick around with an unintuitive product, be it unintuitive by design, omission, or simply poorly-committed programming (the most problematic issue in my opinion). The product is there to serve their needs, not the other way around.

My response to Frank was referring to his statement 'trunking has no place in mission critical functions'; I actually don't disagree with the two of you regarding the usability of the radios, if the system is well-designed and you have purchased a suitable radio with it, it will do exactly what you said you expect it to do but with the added functions that such a system can provide. Those two things do not need to conflict each other, again proven by many TETRA systems that are in use world-wide where voice communication and such features are being used together.

You also need to consider that there can be different users within such a system, i.e. even certain functions may require some users "to fiddle around" with their radio (on purpose, subject to the specific function) it doesn't mean that the fireman rushing into the burning house has to.
We can both make up scenarios for one or the other side of the argument without getting anywhere but you need to let go of the idea that the additional functions somehow mean it impacts all radio user in the system negatively, in fact many of the functions will be entirely transparent to them so they can focus on their mission and not worry about the radio.

You touched upon another issue with respect to data in alluding to the value of data being greater than that of voice.

Neither did I say/imply that data is of greater value nor did I actually limit my statement to data, I said there are other features than voice that those systems can provide (which includes data but also others) and that many customers ask for them / make use of them.
It is for the end-user organization to decide what holds more value to them, or if they are equally important.

Let's take that further to the concept of enhanced situational awareness. How much is too much? Can the vision of some here in the US (streaming video and metric data from everyone and everything on-scene to create a meta-model of the evolution) enhance situational awareness or will it impede it? Assuming this is indeed an enhancement, would direction from a synergy center remove the discretion of those who are actually there? Would this be a shift from discretionary ability to ministerial duty?

You focus on one particular function only and I don't deny that they may later find it creates problems but it doesn't need to be the fault of the technology, in your example it's rather pointing to how you use it.
And that is again for the end-user to figure out and decide, they are not forced to stream video and metric data from everyone just because the system has the ability to do so. If they do and then finds it impedes their operation or creates legal issues then they may just need to review what they are doing and figure out if they need to make changes or give it up entirely, doesn't mean that the system itself cannot be used anymore; instead it can still provide voice comms and, where applicable, many of the other functions that do not create such issues.

Perhaps the most valuable thing any manufacturer can do is stop making four or five figure nifties and toys, and get their behinds out into the street with the people who actually use the stuff to see how their technology can enhance their safety and performance.

Here we go again - the bad, bad manufacturer. Do you realize that most public safety features are developed with input or even by request from end-user organizations? You would be surprised what ideas or expectations they have at times, although manufacturers do come up with features that they think create value to their customers. You are right, someone needs to pay for that, but if all they wanted is just a PTT button for voice comms I think it's reasonable to assume that the manufacturers would have stopped years ago pouring millions into R&D and just mass-produce a single design.

 

[SCPD]

These conventional vs. trunking arguements are 20+ years old.

I think the real reason conventional licenses dominate NYC is due to limited spectrum. It's hard for any one licensee to get enough channels to build a trunked system.

 

[nd5y]

Here is a report about how a wide area TETRA system performed during an emergency situation.
http://dinkom.no/FILES/2011/evalueringsrapporter/use_of_ndnett07222011.pdf

 

[radioman2001]

While the DNK report is subjective to users experiences, I find the following troubling:

"The available feedback from the users so far indicates that Nødnett functioned well. However, the traffic in the talk groups was so heavy that some users had to wait their turn before they could send their messages."

Unacceptable by any standard, at least here in the U.S., and especially for Public Safety, but none the less understandable. It could also be said about this happening on a conventional channel, EXCEPT the user could break in with a MAYDAY, not a possibilty on TETRA.

One of the MAIN reasons why Fire Grounds and even Police Ops are on a conventional and preferably a simplex channel. All NYPD preceint channels have simplex as well as semi-duplex for those exact conditions. Why tie up an entire radio network when you want to tell some one 100 yards away to close a street or watch a door and the like.
1000 radios on system with 300 operating barely equals a few preceints in NYC. There are over 30K officers, if you take 25% of than number and place them on the street with radios that's 7,500 radios covering roughly 110 sq miles. 99% of which only have to cover a 1-2 sq mile area, with a single channel.

The conventional vs trunking arguments ARE 20 years old, but still have a point. Trunking again is good for a lot of users covering a large area without challenging terrain (Buildings, tunnels, etc) with very few channels as compared to conventional, but it isn't the cure all. Conventional with it's simplicity and ease of operation by user, less prone to failure, substantialy lower costs in equipment for both user and infrastructure, which now include software licensing requirements for some trunked systems (you don't even truly your own system), TRUE interoperability with legacy systems, conventional wins hands down.

 

[Boatanchor]

While the DNK report is subjective to users experiences, I find the following troubling:

One of the MAIN reasons why Fire Grounds and even Police Ops are on a conventional and preferably a simplex channel. All NYPD preceint channels have simplex as well as semi-duplex for those exact conditions. Why tie up an entire radio network when you want to tell some one 100 yards away to close a street or watch a door and the like.
1000 radios on system with 300 operating barely equals a few preceints in NYC. There are over 30K officers, if you take 25% of than number and place them on the street with radios that's 7,500 radios covering roughly 110 sq miles. 99% of which only have to cover a 1-2 sq mile area, with a single channel.

The conventional vs trunking arguments ARE 20 years old, but still have a point. Trunking again is good for a lot of users covering a large area without challenging terrain (Buildings, tunnels, etc) with very few channels as compared to conventional, but it isn't the cure all. Conventional with it's simplicity and ease of operation by user, less prone to failure, substantialy lower costs in equipment for both user and infrastructure, which now include software licensing requirements for some trunked systems (you don't even truly your own system), TRUE interoperability with legacy systems, conventional wins hands down.

Well said..

Apples and Oranges. Trouble is not always is the correct fruit choice made lol..

My 'issue' with trunking and many Wide Area networks nowadays is the over reliance on often contested and uncontrolled IP back-haul networks. In the good 'ol days, networks were linked with 'in-house' UHF or microwave links. If a link went down, you as the network operator could go out and replace the faulty equipment. Today, network operators only have direct control over the 'Subscriber Units' and possibly the base stations. The IP networks are all smoke and mirrors controlled by one or more third parties!

 

[scosgt]

The only training program you should need to operate a radio in the public safety field is the ON/OFF and PTT buttons. Anything more than that requires more effort than is needed to do your job.

I realize I am virtually alone in this opinion but I have said it since the beginning: trunking has no place in mission critical functions. There are too many links in the chain that can fail.

Frank is absolutely right. Anyone who has worked as a responder in NYC, or has extensively monitored NYC public safety radio, knows one thing to be true:

There are FREQUENT emergencies where the Officer will press the transmit button and scream for help. No time to press panic buttons, priority buttons, wait for a tone confirmation or anything else.

In Mayberry, or the State Police, actual calls for immediate assistance are less frequent, and the radio systems themselves are often silent. Not so NYPD or NYFD. Some channels are in constant use, and when someone is being shot at or beaten to death, that lifesaving radio has to work just like the Glock the Officer carries - just push the button. Nothing more.

Now I am going to say it is possible to build a pretty darn good trunking system. Port Authority uses an EDACS system that is in fact very busy, and it does seem to work most of the time. BUT, they don't patrol the streets, they have a different mission.

Trunking for NYPD is possible, but IMHO it would be a mistake. The radio needs to transmit the instant the button is pushed, and everyone in the zone needs to hear that transmission as it is made. A computer glitch easily equals death.

As an example, some years ago there was an Emergency Services Lieutenant named Francis LaSala. I personally heard his emergency transmission. He was returning to "quarters" (for his ESU vehicle) and came upon a building fire. He was screaming into his radio on Citywide SOD as he was running into the building. The transmission was garbled, due at least in part to the fact that he was running and screaming at the time. Central kept calling him and asking for the location. He never answered and was killed in the rescue.
Now the thing is, he did not hesitate to make sure he had help on the way. They did not know immediately where to send help. If they had, maybe he would have survived.

My point is, when an experienced elite Officer has a failure to communicate like this, what happens on a trunked system where you are dependent on a computer to give you a channel (on an impossibly busy system) and send your transmission to the appropriate radios in the field? I don't see it as a good thing.

 

[SCPD]

All this talk about instant PTT is great but what to do when two users press PTT at the same time? What to do when you want to scream "help!" while someone else is blathering away?

 

[JoeyC]

"No time to press panic button." Hmmmm. Didn't know the panic button was such an ordeal to get to on the radio. On the trunked system I listen to most, the panic button gets pushed more often on accident than when really needed. When one is activated, the trunking stops and the talkgroup remains open until it is reset by the radio that activated. IOW the repeater is held for the emergency. No busies to wait for.
While I certainly am no expert at listening to PS in the big apple, I've heard enough of the screams and poor radio etiquette on streams and snippets of radio encounters there to know that its probably just as well that the PTT button is the only thing they teach you. K

 

[radioman2001]

Hypothetically since it's not very likely it would ever happen NYPD could NEVER use just one trunking system. While a Type I systems did not have enough ID's for a NYPD system (a moot point) they would probably have to have one for each borough and maybe 2 or more just for Manhattan, the controller could never handle the number of requests for a channel in a reasonable amount of time due to the amount of traffic requests (do the math !). Again you are talking 5000 to 7500 radios on one system at the same time with constant key ups equaling almost full time transmit. I doubt there is ANY trunking system in the U.S. (even a statewide one) right now that has that many users operating at one time (not just on the system but actually requesting channels)
For those that do not live, work or monitor NYC channels a general indication of just how busy NYC is that their 800 system is maxed out and overloaded (and that's for non-PD or FD users), that's why they now have the 480 system, which continues to add user groups of non emergency users. All in all NYC has had a very robust and quite stable conventional radio systems for NYPD, FDNY and EMS for decades, why mess it up with TETRA or trunking in general.

 

[Raccon]

Hypothetically since it's not very likely it would ever happen NYPD could NEVER use just one trunking system. While a Type I systems did not have enough ID's for a NYPD system (a moot point) they would probably have to have one for each borough and maybe 2 or more just for Manhattan, the controller could never handle the number of requests for a channel in a reasonable amount of time due to the amount of traffic requests (do the math !). Again you are talking 5000 to 7500 radios on one system at the same time with constant key ups equaling almost full time transmit. I doubt there is ANY trunking system in the U.S. (even a statewide one) right now that has that many users operating at one time (not just on the system but actually requesting channels)
For those that do not live, work or monitor NYC channels a general indication of just how busy NYC is that their 800 system is maxed out and overloaded (and that's for non-PD or FD users), that's why they now have the 480 system, which continues to add user groups of non emergency users. All in all NYC has had a very robust and quite stable conventional radio systems for NYPD, FDNY and EMS for decades, why mess it up with TETRA or trunking in general.

Here are some examples what a trunked systems can do, just to provide some real-life perspective to your theory:

2008 Beijing Olympics: 90,000 radio users, 1.6 million calls a day
2010 Guangzhou Asian Games: 45,000 radio users, 2.2 million calls during the day of inauguration
2011 Shenzen World University Games: 30,000 radio users, 1.84 million calls during the day of inauguration, up to 140,000 calls during busy hours

All of them are TETRA networks, shared by public safety organisations (and other users) that performed without problem under such load.
And mind you, those are city-wide networks, not state- or nation-wide ones, and users were concentrated within small geographical areas during those events. Each system has ample room for expansion.

Just for arguments sake, but do you still think that TETRA couldn't handle the NYPD? 5000-7500 radios doesn't seem to be a challenge actually, even medium-sized TETRA systems will handle that with ease.

 

[Raccon]

Unacceptable by any standard, at least here in the U.S., and especially for Public Safety, but none the less understandable. It could also be said about this happening on a conventional channel, EXCEPT the user could break in with a MAYDAY, not a possibilty on TETRA.

Wrong. Firstly TETRA has priority features (i.e. certain users can have higher priority than others and thus can jump the queue) and secondly it is also possible to pre-empt other users with the appropiate right, either for speech item or resources. Where applicable dispatchers have even higher priority and pre-empt speech items on demand or always. Similar for talkgroups, i.e. some of them can have a higher priority when "fighting" for traffic channels or (if wanted) pre-empt other, lower priority talkgroups.

Even the radio user in question doesn't have any priority or pre-emption rights all he has to do is to press the emergency button, in which case the system will always do a ruthless pre-emption and free a channel for him if none is available.

One of the MAIN reasons why Fire Grounds and even Police Ops are on a conventional and preferably a simplex channel. All NYPD preceint channels have simplex as well as semi-duplex for those exact conditions. Why tie up an entire radio network when you want to tell some one 100 yards away to close a street or watch a door and the like.

You don't have to tie in the entire network if you don't want to, you tie in radio users that have selected the same group, are scanning the group and dispatchers that are monitoring the group. If the network is smart (and most TETRA systems are) it will not allocate a channel in base stations where there are no group members.

Try that with your conventional system - you want to broadcast in a wide area using simulcast and you do tie in the entire network, always, not to mention that such configuration and connections would be subject to the same issues that you criticize about trunked systems.

So what you are left with is comparing a single-site conventional repeater with a trunked system, which isn't fair to begin with but a TETRA base station can also work in stand-alone mode, yet provide trunking (up to 1 control channel and 31 traffic channels in a single site) and thus maintain frequency-efficiency.
But if your conventional carrier fails you not only loose capacity but you loose that particular talkgroup, too; if the main carrier in the TETRA base station fails the control channel will just be allocated to another carrier within seconds and you only loose capacity but none of the talkgroups.

TRUE interoperability with legacy systems, conventional wins hands down.

'True' interoperability is arguable anyway I reckon, if you want 100% compatibility with the legacy system then perhaps you should just keep using that legacy system.
It seems however that trunked systems are not as bad as you make them out to be and that the organisations, let it be public safety or others, do not want to stick with legacy or conventional systems.