Public Safety Advocate: Turning Push-To-Talk Interoperability on Its Head, Disagreeing with Morgan O’Brien, and the Wireless Dinner at IWCE

This week I decided to once again discuss the urgent need for nationwide Push-To-Talk (PTT) interoperability between FirstNet, broadband, and Land Mobile Radio (LMR). Well, we no longer have to wait for vendors to finally work together. With some vendors’ capabilities, and since many agencies have already deployed their preferred flavor of push-to-talk, perhaps we should look at building nationwide interoperability starting at the agency level and working up.
[Note: None of the vendors mentioned in this article are current clients.]

Push-To-Talk Interoperability Today

Many agencies have moved ahead on their own and worked with an approved FirstNet PTT vendor. Tango Tango has not waited around for the PTT vendor community to solve the interoperability problem. It has found solutions to the problems as it has focused on the agency level.

Tango Tango is not the only PTT vendor that is not waiting around for a solution. JPS Interoperability provides bridging devices between networks and, like Tango Tango, JPS is a white-label ESChat reseller. JPS with its VIA product, and ESChat have been providing interoperability between broadband and LMR PTT for several years. They have taken the initiative to move forward in their own way because they understand that PTT interoperability is a must-have that public safety must have now, not sometime in the distant future.

A number of people involved in the public-safety market still believe all they have to do is wait for the 3GPP to finalize its PTT standard, enable bridging to LMR PTT, and make it readily available.

While some are waiting, the industry is not providing what public safety wants and needs in the way of a fully-interoperable nationwide broadband/LMR PTT solution. While there doesn’t seem to be a definitive way to determine the share of the public-safety market held by each FirstNet-approved PTT vendor, it is obvious that between the Kodiak/Motorola Enhanced PTT network-based offering and the three FirstNet-approved vendors offering the ESChat over-the-top PTT solution, the majority of public-safety agencies at the local, state, and federal levels have chosen ESChat.

Since some vendors do not seem to have any desire to solve the PTT interoperability problem by working with other PTT vendors, perhaps it is time for public-safety agencies to work with the vendors that have already demonstrated they can provide interoperability between FirstNet and broadband PTT solutions and interface these solutions with existing analog and digital LMR PTT systems.

Public safety has waited for and pushed vendors to provide LMR interoperability. This is following in the footsteps of P25, which took more than twenty years, or two decades, to truly become a standard where one vendor’s equipment can be integrated into another vendor’s P25 network.

It was also many years before vendors offered multiband LMR radios even though several public-safety LMR vendors had multiband amateur radio mobiles and handhelds on the market long before LMR Part 90-approved multiband radios became available.

Public Safety Must be Proactive

Having to depend on the vendor community and wait for a solution motivated the public-safety community to combine efforts to push those in Washington DC to solve the spectrum interoperability issue. Thus, the Public Safety Spectrum Trust (PSST), Public Safety Alliance (PSA), National Public Safety Telecommunications Council (NPSTC), APCO, and other public-safety organizations came together and were successful in convincing Congress to pass a law to establish FirstNet.

Today, the Public Safety Spectrum Alliance (PSSA) and the above-mentioned agencies and organizations have once again come together to address the proposed 4.9-GHz spectrum allocation, which is once again before the Federal Communications Commission (FCC).

The public-safety community’s track record when it works toward a common goal remains unblemished. However, now it is time for public-safety agencies to move forward on their own and work with or around PTT vendors in order to achieve full nationwide PTT interoperability.

Turning PTT Interoperability on Its Head

Is it possible to build nationwide PTT interoperability from the ground up instead of from the top down? I think it can be done and it can be done faster than waiting around for vendors to finally recognize that PTT interoperability is what public safety wants and needs.

Based on what Tango Tango, JPS Interoperability, and ESChat have accomplished, we know PTT interoperability is not dependent on vendor consensus or buy-in. While no one oversees the public-safety LMR world, the FirstNet Authority oversees public-safety broadband communications and the contractor building out the FirstNet network (AT&T). Both FirstNet and AT&T know who their clients/customers are and they are committed to making sure public safety has what it needs.

Once an agency joins FirstNet, it is free to use any FirstNet-approved PTT it chooses. There is no mandate or requirement for which FirstNet-approved PTT vendor an agency can use, thus each agency is free to go with its favorite flavor of PTT and its preferred FirstNet-approved push-to-talk vendor that is willing to provide LMR-PTT interoperability. Agencies will be able to communicate with surrounding FirstNet-user agencies even if they have chosen different PTT solutions. Bridges are used to enable communications between different flavors of PTT and between broadband and land mobile radio PTT.

Unless an agency’s LMR system is purchased as a service and an LMR vendor built out the system, it belongs to the agency that purchased it and the agency can choose its favored FirstNet-approved PTT vendor. We have already discovered that some vendors are much more willing than others to integrate their PTT with other PTT systems to provide full PTT interoperability, and as we have already seen, agencies do not need “permission” from a PTT vendor to more fully integrate its PTT broadband and LMR PTT systems with other vendors’ PTT systems as long as the various agencies are agreeable. 

The Devil Is in the Details

As some FirstNet-approved push-to-talk broadband vendors have demonstrated, different flavors of broadband and LMR PTT can be tied together. However, there are some issues that will need to be addressed if we are to grow a nationwide PTT interoperability solution on an agency-by-agency basis. Even so, I believe these can be resolved to the benefit of the public-safety community. 

One concern is the ability to quickly set up interoperability across agencies even if they are using different PTT technologies. This can be solved in a manner similar to how the National Public Safety Telecommunications Council (NPSTC) went about setting up nationwide LMR interoperability channels. With coordination and a concerted effort, cross-agency interoperability is possible. And I believe it can be achieved faster than if public-safety waits to see how and when network operators will provide a solution for full FirstNet/broadband/LMR interoperability.

For many years, public safety has had to deal with the lack of interoperability caused by agencies being licensed over a long time span and in diverse frequencies in the radio spectrum. Nationwide interoperability was finally made possible only after major disasters made Congress, the Executive Branch, and citizens acutely aware of what public safety has had to cope with since 1930.

The FirstNet nationwide broadband network has had a huge impact on how public safety provides services to the public and how prepared first responders are as they head toward an incident. FirstNet began in earnest in 2017 and has continued to be developed at a fast pace. According to AT&T officials, FirstNet (Built with AT&T) is 95-percent complete, well ahead the five-year buildout window specified in the contract awarded to AT&T by the FirstNet Authority. More and more agencies have signed up to use FirstNet and for the most part, coverage issues have been addressed. 

What has not been addressed is the problem of when an agency in San Diego, for example, travels across the United States to assist with an incident in, say, Florida, without being able to use voice to communicate with agencies at the scene during their cross-country drive and when they arrive at the incident.

We have come a very long way thanks to FirstNet. Now I think it is time for the public-safety community to figure out how to provide push-to-talk interoperability for FirstNet, broadband, and land mobile radio public-safety users. I believe we can get there faster and more efficiently by working from the ground up.

Morgan O’Brien, I Disagree

For those who may not be aware, Morgan O’Brien was a Nextel cofounder and has been an active supporter of the public-safety community for many years. He was one of the first to stand up and say it was time for public safety to take a look at broadband communications.

More recently, O’Brien has been involved in the effort to convert 900-MHz narrowband spectrum to broadband spectrum to make way for new systems to be used primarily by businesses and others that want to use broadband spectrum for their networks.

Recently, he commented that land mobile radio users (without specifying public-safety, business, or both) should start aggregating their narrowband spectrum to accommodate more private broadband networks. In a previous Advocate, I further pointed out that some within the FCC believe all spectrum should be pooled and turned into broadband spectrum so a multiplicity of users could share the same network(s).

I disagree with both of these ideas for a number of reasons. One is that land mobile radio today is capable of what I call “graceful degradation,” which means there are progressive fallback modes if the main mode of LMR communications fails. Another reason I oppose converting LMR spectrum to broadband is that as has been demonstrated by FirstNet, and now other broadband vendors, even with priority and preemption for public safety, there are issues with network capacity, resiliency, and redundancy.

Another way to look at this is that not all spectrum is equal when it comes to broadband services. For example, trying to convert VHF and UHF systems to broadband-only will require form-factor changes, antenna changes, and more.

I am not opposed to finding better ways of sharing spectrum, but I do believe local, state, and federal public safety need dedicated spectrum at least some of the time. Band management or band clearing when the spectrum is needed by critical-communications services could be difficult if different user-groups with their own priorities are sharing the same spectrum. Should the Secret Service, FBI, and DEA have to operate on the same broadband spectrum as the local plumbing company or those streaming Netflix or YouTube? Should public safety be required to operate under the same conditions?

There is no doubt that we need to take a new and smarter look at frequency allocation as we move forward. And there is no doubt that we need more and different methods of spectrum-sharing because there is not enough spectrum available to meet the demand. The question is how to balance the needs of critical-communications systems and services, services that need instant access, and consumers who need instant access to call 9-1-1 in an emergency when the demand for data continues to outpace spectrum availability?

Even with advances in 5G and soon 6G, there will never be enough spectrum to meet everyone’s needs/ wants. Therefore, some form of priority is critical for times when public safety needs spectrum to coordinate incidents and deliver information to first responders to better prepare them to resolve incidents and to save lives and property.

Winding down

Wireless Dinner at IWCE 2021

IWCE 2021 ended Thursday and a number of us gathered for a dinner that evening. Our guests ran the gamut from vendors to broadband service providers to state communications professionals. Chief Harlan McEwan (Ret), the Father of FirstNet was there as was Martha Ellis, Executive Director of the Public Safety Broadband Technology Association.

We met for dinner at Pieros, which is a wonderful Italian restaurant close to the Convention Center. The Private Wireless Forum (PWF) used to meet at Pieros on Thursday evenings after IWCE, and NPSTC held several dinners at the same location. Here is a picture:

Thursday’s dinner started out like our “Wireless Dinners” did with about ten guests and we had a great time. This dinner brought back memories of the beginnings of our series of Wireless Dinners that we hosted for 21 years. After the first year, the Wireless Dinner grew to twenty or thirty as others asked to join us. The early Dinners were held during Comdex, we signed on sponsors, and the event grew to 200-250 guests with a fun program that included a presentation by a noted futurist. As Comdex was fading, we moved to the second night of the CTIA spring conference. By the time we hosted our last Wireless Dinner at CTIA, it had become by invitation only and about 300-plus people attended. Producing the Dinner each year took a lot of time and effort, but it was very rewarding. 

When I talk with people who have been in the industry for a while, they often reminisce about the Dinners and how much they enjoyed them. Just to be clear, it is not my intention to grow into another Wireless Dinner series of events! However, I am hoping someone will decide to host a similar series of dinners and as part of the program, they will honor people who have had an impact on the wireless industry, especially public-safety communications. Currently, there is no organization that hosts an event such as this, but I would like to see one and I would like it to include a formal induction of public-safety communications professionals into what I would call the “Public-Safety Communications Hall of Fame.”

Until next week…

Andrew M. Seybold
©2021, Andrew Seybold, Inc.


2 Comments on "Public Safety Advocate: Turning Push-To-Talk Interoperability on Its Head, Disagreeing with Morgan O’Brien, and the Wireless Dinner at IWCE"

  1. Enjoyed the dinner Andy, and as usual your thought provoking commentary on the challenge of solving PTT interoperability.

  2. John Contestabile | October 15, 2021 at 2:41 pm | Reply

    Boy those are some of the usual suspects in that photo! bravo!

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