PSA Discovery Patterns Weekly News Summary

Thu Mar 31 20:07:12 2016

Mission-Critical Push-To-Talk (PTT) over FirstNet

After I published last week’s news piece I received some other information, mainly from members of the Public Safety community who had been at IWCE, about the amount of hype and, to them, unrealistic claims regarding how soon and how wonderful Mission-Critical PTT over FirstNet will be. As I said last week, there are some, most of whom have never been involved in an incident as law, fire, or EMS, who seem to believe that once standards are created the rest simply happens. As I was digesting this I received a tweet about a blog written by the FirstNet CTO regarding Mission-Critical PTT. (Can we please call it Public Safety Grade?)

After reading the blog I feel much better about what is going on and the time frame for all of this (not soon). The entire blog can be found at and is worth a read. The major takeaways for me were the bullet point items recapping what was discussed at a joint meeting of the CTO and User Advocacy teams of FirstNet, and PSCR (Public Safety Communications Research, a NIST organization working in cooperation with FirstNet and the Public Safety community). This blog is the first indication I have had that those moving forward with plans to implement PTT over FirstNet have come to the realization that there remains a lot of work to be done in addition to the passage of the standard. There are two sets of bullet points in this blog and both are worth repeating here.

The Roundtable was designed to:
 Begin the research effort to ensure that public safety has access to Mission Critical Broadband solutions, which are critical to the deployment of the nationwide public safety broadband network (NPSBN);
 Validate previous interviews of public safety conducted by PSCR;
 Validate the research approach for Mission Critical Broadband, which is one of the primary research areas identified in the legislation that created FirstNet; and
 Characterize the key features that make up MCV today (Direct Mode, Push-to-Talk, Emergency Alerting, Group Communications, Audio Quality, and Talker ID), including associated key performance indicators (KPIs) and challenges.

I believe the last of these bullet points is the most important in that it is a positive indication that FirstNet wants to learn what is really needed and get it right the first time around. The research and funding are PSCR issues dealing with the FirstNet legislation funding that provides money to carry out this work. I hope as it conducts its research FirstNet does not limit its investigation to P25 Digital PTT and its feature set since much of the United States is still using analog (FM) communications and analog PTT, which do not have as many requirements. I believe ALL P25 digital features need to be included in the final released PTT system AND that the standard for Mission-Critical PTT is only 50 percent of the equation. Without a Mission-Critical network to run over, Mission-Critical PTT cannot be truly Mission Critical. Which brings me to the next set of bullet points in the blog that seem to indicate there is a level of understanding among some of those involved in this project:

 Emergency Buttons: “Emergency Buttons” function differently across current Land Mobile Radio (LMR) systems both on and off network. One of the key take-aways from the discussion was the need for flexibility configuring the emergency button. The LMR systems in place today allow the local jurisdiction to program both the system and the radio to meet the operational requirements of the users.
 Local Control: In current LMR systems, a local jurisdiction can modify a channel plan/talkgroup plan. Public safety communicated the need for administrative privileges to add or remove talkgroups and to set voice traffic access and priority.
 Audio Quality: Members of public safety described the challenges encountered with audio quality on digital Project 25 (P25) LMR radio systems. Public safety reinforced the need to duplicate real world environments encountered by first responders during lab testing to ensure that a broadband or Long Term Evolution (LTE) system performs adequately.
 On Network and Off Network functionality: Public safety described the use of off-network communications today. Based on agency/jurisdiction specific operating environments and coverage areas, some agencies/jurisdictions use on network (trunked) communications for operations and others do not. The procedures governing on versus off network may not be consistent inter-agency or intra-agency and will be a key concern in migrating direct mode to broadband. Public safety also prioritized the need for broadband systems to operate off-network and communicate in and out of buildings or other structures.
 Key Performance Indicators (KPI): PSCR emphasized the need to identify strong KPIs for each required feature. KPIs provide measurable performance standards that PSCR, FirstNet, and others can use to objectively measure whether public safety is receiving truly MCV level service. This will be important in the future to determine if the performance functionality meets operational requirements of public safety.

These points are all good with the caveat that PTT is used differently by different agencies in different parts of the United States so there is a need to broaden the base of those who contribute to the information that will be used to define the final PTT service. The next steps listed at the end of the blog are also positive, except perhaps that they do not include existing LMR and commercial PTT vendors as part of what the PSCR is setting out to do. There is already a lot of valuable knowledge and experience out in the world so relying on a research facility without including others who have already helped define and implement PTT over Analog FM, P25 digital, and both 3G and 4G (LTE) broadband networks does not seem like a logical path forward to me. Companies such as Motorola, Harris, Kodiak Networks, SLA (ES Chat), Qualcomm and others have already built and delivered PTT services over broadband that meet or in some cases exceed the P25 PTT capabilities today. I hope these and other companies will be consulted and asked to contribute to the final Public Safety Grade PTT over LTE service when it becomes a reality.

Funding FirstNet 

While working on a team planning a response to the FirstNet RFP, I spent much time focused on a number of key issues including rural coverage, satellite backhaul for both LTE and LMR, and the potential number of first responders or potential FirstNet device users on duty during any given shift. Since then I have been working on identifying differences between areas of the United States that will need to use FirstNet secondary spectrum and areas where network operators already have adequate spectrum for current and projected customer demand. In such areas the FirstNet RFP winner may not have sources of revenue beyond that generated by the Public Safety community. Or what about an area where FirstNet and the vendor commit to building out the network and then that area decides to stick with its existing commercial broadband provider and there is also no need for the secondary FirstNet spectrum? Such a potential FirstNet market territory within the United States is what one might call an economic sinkhole, at least for as long as first responders are not using FirstNet and there is no demand for the secondary spectrum.

I am sure those intending to respond to the RFP are aware of these issues. It is, indeed unfortunate that only two primary types of income are available to the vendor and therefore to FirstNet. These are income from the Public Safety community and income from the secondary spectrum usage where it is needed. Some potential vendors, I am hearing, are talking about leasing portions of the secondary spectrum to a specific user category while others may offer it to other types of users.

However, in the course of my consulting activities we may have uncovered a third (and legal) income model that the winning vendor could effectively employ. This method of funding could be applied to areas were the secondary spectrum is not in demand and where there are sinkhole areas.

I am not talking about the Rivada model of leasing spectrum by time to other network operators who may need it. If Rivada is the successful bidder I suspect it will have already addressed this issue, and the other bidders probably think they have, too. Nor am I talking about reselling network capacity to specific types of large companies as an additional revenue-generating options in problematic market areas.

I believe there are yet other viable and practical options for generating additional revenue. However, I am not aware of these options having been previously discussed and explored, much less quantified to determine the economic impact for the vendor that will provide the FirstNet network.

Finally, this week as the deadline for the RFP is fast approaching, hopeful bidders are busy putting together their spreadsheets and sales plans as they evaluate the pros and cons of responding. I am hoping FirstNet will continue to offer changes to the RFP that will increase flexibility for vendors to make the FirstNet network a reality including, perhaps, some additional funding models.

Andrew Seybold

This is the previous week’s news feature. To receive current mailings of news stories with links to articles each Friday, subscribe for FREE to Andy’s Public Safety Advocate Discovery Patterns Weekly News Summary, Click Here


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