Wireless cellular communications keep growing and are imperative for emergency responders. The Homeland Security Department’s Science and Technology Directorate has an ongoing research program for the development of cellular. Sridhar Kowdley, technology manager for the Science and Technology communications and networking technology center, spoke to the Federal Drive with Tom Temin for details.

Interview transcript:

Sridhar Kowdley: One of the things that we’re looking at consistently and constantly is, since we are the research arm for DHS as well as first responders nationwide, we focus on communication systems and how do as the first responder and or DHS operator communicate in the field because we continually rely more and more on communications and the ability to send data, not just voice, even though voice is still a primary killer app for us. We want to be able to get significant data across, whether it’s video, images and/or file sharing to do our job effectively and efficiently. So in terms of what we do is we begin by looking at what do we use, what are our toolset? How do we operate? What are the research gaps? At which point, DHS S&T comes in and starts saying, ‘How do we close these gaps that we’ve identified in R&D?’

Tom Temin: Right. And just a brief then thought on the idea of voice being still significant, but a voice has to be accompanied by data. Generally, what does that do to the old push-to-talk type of thought?

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Sridhar Kowdley: Well, it really brings it to the forefront. Keep in mind that we’ve often heard that voice is a killer app. But increasingly, we’re starting to get data is a critical requirement. I’ll give you a great example. We were working with Customs and Border Protection and we were working on a number of challenges for them. A lot of times, these Border Patrol agents leave their cars and then they’re not connected for five hours. So they’re essentially out of pocket. And so when we were looking at, ‘Well, do you need data, do you need other information?’ There was a young Border Patrol agent who had just joined and said, ‘You know what, we’ve got a lot of ultralight flying into the country.’ We want to be able to get tail numbers. We want to get images of it. We want to know where they’ve been, where we saw them. So this is critical information for us in terms of trying to understand that type of requirement in terms of pushing data increasingly with first responders and fire teams. You want to go into a building? We want to know what does that building, what are the sensors? Are we going into a potential hazmat area? How do you know? Right. So, yes, voice is still important and it’s critical. If I’m hurt, I need help, for first responders or DHS staff to be able to reach out, that’s still the killer app. However, increasingly sensor data, LoT devices, other things are going to drive how we approach our mission moving forward.

Tom Temin: Right. So then you are dealing with multiple file sizes to get right down to it. If it’s sensor data, it could be much smaller than a picture or a map of a building or this kind of thing. And also, well, that means different bandwidth requirements. And how does that all relate to, I mean, none of this works by radio frequency. It’s all by cellular then, correct?

Sridhar Kowdley: So, yes, to a large extent. Looking at 3G, 4G or 5G, we can push data across. Increasingly, we’re starting to look and say, ‘Well, how do we rely, traditional LMR. Land-mobile radio is great. They have really high power, large batteries. They communicate at very low bands. But again, they’re low band. They carry voice predominantly and very, very limited data. They can send things like location and a few other things. But generally, it’s limited to voice. So we’re increasingly starting to rely on cellular data for a number of reasons. One is who doesn’t carry cellphone? Everybody does. Increasingly is starting to play a bigger role in what we do. So we are starting to look at the use of cellular data and information for doing our mission. And increasingly, technology is ramping up. It’s becoming more available to us, specifically with our great partner in Commerce, FirstNet. FirstNet is now, they have a partnership with AT&T providing mission grade public safety communications. The other carriers are coming along as well. But we cannot rely on a single network, regardless of how resilient or good it is. You have to be able to be flexible and resilient. And one of the things that we look for is high resiliency because the comms cannot fail. We have to be able to provide comms and information, regardless of file size or any of those things. So it’s that connectivity should be always there and available so that we can do our mission effectively and safely because ultimately our mission is to save property, save people, save to our critical mission at the actual edge of the network.

Tom Temin: Sure. And you also mentioned that who doesn’t carry a phone nowadays as a good basis for this. But the phones themselves are more than phones. They’re cameras. They’re computers. They have Bluetooth. They have motion sensors and so forth. So it’s really you’re looking at them as much for their multimodal data ability as their phone ability.

Sridhar Kowdley: Absolutely. I mean, they are a tool kit. There certainly some capabilities. The internal guts of the phone have tremendous amount of sensors on them. For example, we were looking at the ability and I think Apple Watch does this as well as a great sensor. If you fall down, Apple Watch can automatically call 911 and say, ‘Hey, I’ve fallen down,’ especially for elderly people. Also for if you have a public safety agent who just falls over and the accelerometer within the phone triggers, then you need help. Or it could be a trigger to say, ‘Hey, do you need help,’ kind of a thing. So certainly, yeah, it’s critical and vital. So we’ve been looking at cellular technologies and capabilities to integrate into the existing land mobile radio framework.

Tom Temin: And cellular networks, of course, are shared. There a type of mesh, I guess you might say. And so with the FirstNet program, there is a priority tunnel, if you will, for lack of a better word, through that particular network. Talk about more how you get resiliency and also priority, I think, is crucial. What are your strategies for that side of it?

Sridhar Kowdley: Sure. I’ve got to give kudos to CISA, DHS Cybersecurity Infrastructure Security Agency. They actually have been shepherding and leading something called wireless priority services in the 3G, 4G world. And that basically allowed users to kind of ramp up and get priority services. The difference now with FirstNet and as well as some of the other carriers are now providing what they call quality of service. And they also have key performance metrics that they look at. And what they’re doing now is prioritizing first responder communications significantly higher so that if we get into an opportunity where we have something called ruthless preemption. Before it used to be that I couldn’t interrupt you if the channels were busy, but I would get first shock when a channel opened up with wireless priority services. Now they’ve actually gotten to the point where they could ratchet down the public safety, somebody who’s streaming Netflix, for example, and give priority to either fire or law enforcement or emergency medical services to give them the bandwidth that they need to do their work. So certainly we’ve been working with them. CISA has been doing a great job. In fact, they run a number of field trials. They just did one at July Fourth at the Washington Mall to take a look at streaming video and how it performs. And they invited all three of the major carriers to play and get data and feedback to improve that reliability, specifically for public safety.

Tom Temin: And when that priority is invoked, say to neck down junior that’s looking at Netflix so that the police and fire operators or FEMA, whoever it might be, can operate, then how does that happen? Is that something that the carrier has to invoke from some command center or can this happen locally?

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Sridhar Kowdley: So there is a couple of metrics and capabilities there. But I mean, in general, if you’re a public safety user and you’re defined as such, either at the network level as part of your subscription, you’re given a certain priority status. Now, what could happen and you talked about push-to-talk earlier, the 3GPP standard also allows something called mission-critical services, which is not only push-to-talk, but it is sort of high prioritize video and text and other services that the standard allows. And what that does is actually ties into the network core itself. So the network automatically makes decisions to say, ‘Hey, here’s a high priority user and voice is given the most. The highest priority next is other video or data services. But there are key performance settings that you can set on the network that immediately, if it’s invoked and capacity is at a capacity short, it will start shedding loads to allow these people to get on. Now, keep in mind, that’s if a network is available. Right. And if the network isn’t damaged. Right. So that’s another critical thing that S&T is looking at. How do we make networks resilient? How do we make them operate through?

Tom Temin: Right. So that gives. Well, I have a couple of questions. One on getting back to the high priority, is priority equivalent to having a VPN capability across that cellular network or are those two separate things?

Sridhar Kowdley: I believe VPN does provide some stability, if you will, in maintaining a connection. But it’s really two different things. When you talk about prioritization of service, you’re actually looking physically of that cell site. What is the capacity and how do I make resources available for this public safety user to actually connect? And I think we also talk about things like network slicing. Network slicing, also, what it does is it creates an artificial pipe from source to end destination. What it does is it says it works with the network itself to guarantee certain performance levels. And we’ve actually demonstrated this and work with it in the lab with one of our researchers. And what we found is that if you had a standard traditional network and once the network got busy, your video started becoming choppy and unusable. But if I have that network slice with certain performance parameters set, I can now ensure that video is seamless and it works through. And obviously, that level of ability to communicate and operate through whatever the congestion is and or the issues also helps provide a huge number of verticals behind it, such as artificial intelligence and machine learning. And all of those things come into play because if I’m relying on data coming in and that data doesn’t come in, then I can’t have the AR tools work for me.

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