Ten questions you need to ask yourself before choosing (between) PoC and LMR

Customers are sometimes faced with the choice between deploying a (or enhancing an existing) LMR system or implementing WAVE PTX. I’ve compiled a list of questions, I think, customers need to ask themselves when making this choice.

For the purposes of this post, I’m only going to consider WAVE PTX and MOTOTRBO. Someone faced with this decision, needs to consider all of the below points as part of their decision-making process.

For those who are not familiar, WAVE PTX is Motorola Solutions’ subscription-based group communication service that connects teams across different devices, networks, and locations. It offers the simplicity of professional radio PTT communication with the ability to share details via text, photo, video or file attachment. It works on 4G; 3G and Wi-Fi networks.

Regular visitors to this Blog will certainly know what MOTOTRBO is. For those who don’t, here is a (hopefully good) explanation.

So, when choosing a radio communications system, what do you need to ask yourself?

Where do you need to communicate?

WAVE PTX operates across Europe on all networks ensuring almost 100% coverage. This means you could communicate with your team members in different countries. This would be very useful for transportation companies who have trucks traveling across many countries or for couriers who need coverage across a very large area.

Although a MOTOTRBO system can provide national coverage, many customers tend to use it (or whichever LMR system) to provide radio communications within a defined area such as a factory; airport or province. There are only a handful of MOTOTRBO systems, as far as I know, that provide uninterrupted coverage across more than two countries.

Another thing to consider, is that mobile phone networks do not cover some areas. Examples of this are basements; rural areas and walk-in refrigerators. Of course, for in-building coverage, you can use Wi-Fi or install LTE repeaters but none of these come for free.

So if you need to communicate anywhere across the country or within Europe, WAVE PTX is the better choice in this regard. But, if you need 100% coverage in all locations of your facility, MOTOTRBO is a better choice.

Do you need to use things like video and broadband data?

If you use WAVE PTX on the Motorola EVOLVE; LEX L11 or a (BYOD) mobile phone, you can share video; photos and files with team members via the WAVE PTX app. It is possible to share files via another application but this may be unwise when it comes to IT security. Also, in some cases, the use of certain apps (e.g. Dropbox) may be disallowed by your company's Mobile Device Management.

MOTOTRBO does support data but this is very low bandwidth (ca. 1kbps) and applications which send bursty data are best. You can use the ION portable to do voice across MOTOTRBO and broadband data across WAVE PTX.

How important are things like user priority and availability to you?

Since WAVE PTX uses the public 3G or 4G network, your communications is provided on a best effort basis by the network operators. In Europe, WAVE PTX uses a roaming-SIM so if there's no coverage from one operator, you can get coverage from another. Also, the public networks do not offer any form of user priority so if a site is congested due to a major event, your communications will be interrupted.

If ever there is a natural disaster such as a hurricane; earthquake; floods; fire and so forth, one of the first things to fail are the cellular networks. This is because these have not been designed to be resilient.

Here MOTOTRBO (or any traditional LMR technology) wins outright: in all of the natural and man-made disasters over the last few decades, while cellular systems were down, radio provided vital communications for public safety authorities. This is why many, if not all, public safety organisations still rely on radio for voice communications.

What about the Armageddon scenario?

Imagine, if you will, the worst possible natural disaster: all infrastructure is destroyed – this includes radio and cellular.

In such a situation, with MOTOTRBO, you can communicate on simplex and cope with short distance (ca. 5km) communications when there is no repeater coverage. If a repeater site managed to survive whatever happened, but has lost connectivity with the rest of the network, you would be able to have local site coverage (ca. 25km or more) which should suffice until network connectivity is restored.

In such a scenario, with WAVE PTX, even if the 4G base station has lost its connection to the internet, your device is a paperweight (unless you have some good music stored in memory).

Yes, there is 3GPP Rxx ProSe Direct Mode but the average device is going to put out maybe 200mW ERP at above 800MHz which might get you one or two kilometers, maybe.

Further to the above two points, you need to think about the following:

1. If a major event occurs; the mobile network is jammed and I cannot get reliable communications, what will be the impact? How often or how likely will this event occur?
2. If a major disaster occurs; the mobile network is down and I cannot communicate whatsoever, what will be the impact? How often or how likely will a major disaster occur?

Do you want to own the infrastructure?

With WAVE PTX, the radio network is owned and operated by any one of the mobile operator and the switching/management by Motorola Solutions. You only pay a subscription and have no worries about the network. Many customers prefer this route.

With MOTOTRBO, the radio network etc. usually belongs to you. The only ongoing cost would be the spectrum licence you pay to the regulator. The network would either be maintained by the customer or a service provider (e.g. a Motorola Solutions Channel Partner or even Motorola Solutions themselves).

The advantage with WAVE PTX is that there is no radio network to maintain Adding new devices or making changes to them, is very easy as everything is web based.

How do you feel about the cloud?

WAVE PTX is cloud based. The Roman poet and philosopher Lucretius, once said “Ut quod ali cibus est aliis fuat acre venenum” – in English “That which to some is food, to others is rank poison.” Some people are quite happy to have their data in the cloud, some people not.

With MOTOTRBO, all management and communications happens within your network and is under your control. The risk here is that you need to make sure that OS patches are in place and that the network is not vulnerable to cyberattack.

How do you feel about a subscription-based service?

WAVE PTX is subscription based. For many customers, this means regular predicable costs.

With MOTOTRBO, the only ongoing cost would be the spectrum licence you pay to the regulator. If anything fails outside of warranty, the cost of repair is bourse by the customer – unless there is a maintenance contract in place with a service provider.

Where are you?

Currently, the WAVE PTX service is available in a number of countries. In countries not served by the embedded-SIM, the user/customer will need to provide their own data SIM pay for that as well as the WAVE PTX service. For some, this might be a turn-off.

Do you need to communicate with non-traditional radio users?

Not everybody wants to walk around with a two-way radio. Some users may only need to communicate sometimes. WAVE PTX allows you to communicate with colleagues using their mobile phone or a PC.

MOTOTRBO is also able to communicate with WAVE PTX devices, either using Wi-Fi; LTE or via a radio gateway. So no matter what you choose, non-traditional radio users are covered.

Do you need things like ATEX intrinsic safety?

Currently, there are no WAVE PTX capable devices that are also ATEX certified. There may be ATEX tablets and smartphones but the ones I’ve seen so far are, well, not very good.

MOTOTRBO portable radios are available in both ATEX and TIA4950 variants so can be safely used in hazardous locations such as oil refineries.

In summary

Each of the above points needs to be evaluated based on its relative importance. In the case of resiliency and reliability, you have to also consider the risk and impact of the different disaster and major event scenarios.

Sometimes, the answer may be to use both technologies! In which case, have a look at this.

If there are any other points you think I've missed, feel free to add them in the comments. If you disagree with anything I've said here, please feel free to challenge me on this.

If you are in one of these countries and need help on making this choice, get in touch with me or one of my sales colleagues.