Many of my Public Safety Advocates start out when I am asked a question that gets me thinking. This Advocate began when a good friend of mine who owns a company that specializes in all sorts of surveillance and stakeout communications equipment called to ask if FirstNet would permit agencies to use fixed surveillance cameras over the FirstNet network. His question was prompted by one of his customers who was using hidden video cameras disguised as items you would normally see on a street. I do not have an official reply to the question but the issue certainly needs to be explored and carefully examined.
These High Definition (HD) cameras, which use a lot of bandwidth, are being used on both Verizon and AT&T LTE commercial networks and while they are used only on-demand, they are still fixed and in operation for four to six hours at a time. This agency has experienced its video streams being reduced to slower speeds after only an hour or two. The agency wants to move these devices to FirstNet but needs to know if FirstNet would accept them being on the air from fixed locations. I have sent this query up to the FirstNet folks but have not yet heard back. I suspect the answer will be the same as on the commercial networks because the cameras are at fixed locations.
FirstNet was designed to provide data and video services to public safety and it has always been part of the plan to enable video feeds to and from incidents while they are happening. However, fixed HD video is another story and could prove political for FirstNet even with all the AT&T spectrum available to FirstNet users. Video is used during incidents. Dash and body cams generally record video and only send it out on a broadband network during an incident where it is important for others to observe in real time. Most fixed cameras in cities and elsewhere are connected via fiber or, in some cases, wirelessly using 4.9-GHz spectrum. At the moment, this spectrum is available only to public safety but if the Federal Communications Commission (FCC) has its way, it may end up as shared spectrum.
For the purposes of this article, we are only considering fixed HD cameras, even if they are not fixed in the same location all the time but moved from area to area after some long period of time. The reason for being cautious about HD video from fixed locations is that cellular networks were designed for mobility and not fixed devices. Each cell site is engineered and tuned so there is a certain percentage of the spectrum within that cell sector or site that is not used but is reserved for sessions moving into that cell from another site that need to be accommodated. The math is complex but it works and if a number of fixed devices that use a lot of network bandwidth and capacity are introduced into a cell site, the management of that site becomes problematical.
FirstNet offers unlimited data but that does not mean the network can sustain any number of fixed, high-bandwidth devices. Yes, citizens are streaming more and more HD programming, which is one of the reasons FirstNet’s Band 14 spectrum is important to AT&T. In major metro areas AT&T provides its customers with additional capacity unless public safety needs the spectrum and then, that need is usually only in a specific area impacting a specific number of cell sites. The rest of FirstNet Band 14 is available on a secondary basis. However, citizens are generally streaming while moving from location to location and if they are streaming in their office or home, it is generally using Wi-Fi instead of LTE. Even then there are times when customers abuse the network and have to be “reminded” they are sharing a resource and it is not all theirs for the using.
It is interesting that when machine-to-machine communications was finally embraced by commercial network operators it became known as the Internet of Things (IoT) and in most cases there are or will be separate IoT networks to handle this traffic. While most IoT devices use very little data, there are more devices than people in the world and even the low data rate fixed usage of some IoT applications could cause congestion issues for commercial broadband networks.
Even before FirstNet was established, those of us working on obtaining the spectrum were concerned that even with 20 MHz of spectrum (the 10 already allocated to public safety plus the D Block) in certain cases, during an incident there would not be enough network capacity and bandwidth to serve the needs of the public safety community. During this time, we were hired to run tests on the 5X5 MHz public safety system being installed by the East Bay Regional Communications System Authority (EBRCSA) in California. We ran an extensive series of tests measuring network capacity within a short distance of the cell center, at about mid-point, and at the very edge of the coverage of a cell. The results were published and submitted to the FCC and to Congress and proved that even 20 MHz of broadband spectrum would not be enough given some types of incidents.
Fortunately, when AT&T responded to the FirstNet Request for Proposal (RFP) it added all of its own LTE spectrum to the FirstNet system. Yes, this spectrum is shared by AT&T’s customers, but the result is that during incidents there is more spectrum per cell site available than we would have had if the network was limited to only the FirstNet Band 14 spectrum. Public safety has priority and pre-emption over all of the AT&T spectrum and is not limited to FirstNet Band 14 spectrum, so the need to use pre-emption during incidents is certainly diminished.
Still, even with all of this spectrum it is important for public safety to be mindful that wireless spectrum is a finite commodity and we need to be aware that in addition to public safety communications there are millions of other customers on this spectrum. Further, while public safety certainly has full pre-emptive use of the spectrum when needed, there are things we need to be careful of and one of these is HD surveillance over FirstNet.
As FirstNet and the other commercial networks roll out 5G small cell technology, data rates and network capacity will go up in metro areas and other areas where it is economically feasible to deploy 5G. Smart cities will help, but we must still be aware that this is a shared network—even within the public safety network. In the world of Land Mobile Radio (LMR), each agency normally has its own LMR network or is part of a trunked system where its units are independent from others. Under FirstNet, all of the public safety community at an incident will be sharing the FirstNet bandwidth. This means law, fire, and EMS will all have to be aware of the demands for the spectrum during an incident. As the EMS community gains more and more capabilities in the field including ultrasound, the amount of bandwidth it will need will go up.
If you remember when AT&T was the only network to support the brand-new iPhone, both Apple and AT&T were caught flatfooted by the demand for bandwidth. We did not have LTE then, it was 3G, but in some parts of the country it became almost impossible to access the network. The lessons learned from network overloads not only during the first iPhone but also during civic events and sports events kept network operators scrambling to meet this demand and it continues to grow with every year.
That is the reason pre-emption was a must-have for public safety but we have to appreciate the fact that it is available and follow the rules established by FirstNet (Built by AT&T). As I said earlier, I do not have an answer from FirstNet on the use of the network for fixed HD surveillance cameras but when we do have an answer I hope every agency will understand if there are limitations placed on this form of high bandwidth data.
NOTE: Next weeks Advocate will be delayed a few days because of my involvement in the APCO conference until mid-week.
Andrew M. Seybold
©2018, Andrew Seybold, Inc.