As initial vendor solutions begin to be tested under the Public Safety Communications Research (PSCR) program, the highly anticipated arrival of Long-Term Evolution (LTE) technology promises to radically transform critical communications forever — although not necessarily in the way many users or incumbent radio vendors expect. As other markets already have experienced, the focus of discussions will shift from network capabilities to the broad portfolio of emerging software applications — and the new intra- and inter-organizational communications enabled by them.

There always will be a need for ruggedized devices that support talk-around and other required on-scene communications for first responders. Consequently, land mobile radio devices today and in the future will have an important role in critical communications.

However, Internet Protocol-based systems today are a fundamental component not only of military communications, but also of the ongoing operations of virtually every major corporation. Some of those communications are transmitted over private networks, while others are transported over public networks, including the Internet. There are many well-accepted and advanced means of securing communications over interconnected IP networks, and there are instances when extending these communications out to the hinterland territories of the Internet are perfectly acceptable and commonplace. Public safety will by no means be blazing new paths in this arena and can leverage what has been proven in other industries.

The use of IP-based systems for tactical public-safety communications has been hindered for a fairly simple reason — private LMR networks don't support it. Even with the advent of Project 25 in the U.S. and TETRA elsewhere in the world, the support for data and applications on these networks is significantly limited. With LTE, however, public safety will have the opportunity to leverage a broadband wireless network technology that is built for IP-based communications. In addition, agencies will be able to deploy their own private networks and enter into the communications era that most other industries have enjoyed for years.

These private networks will utilize the same technology and products that will be deployed by public LTE network operators, therefore enjoying the price benefits and innovation driven by the buying power of the public network operators. Even with separate network deployments, there are fantastic opportunities for sharing costs (land, towers, buildings, and backhaul) through public-private partnerships with carriers, which should be encouraged.

Surely, the fourth generation of wireless technologies, as represented by LTE, will need to interoperate with LMR — but its focus is not to replace LMR. Instead, LTE will provide an incredible first step towards the deployment of broadband wireless networks that are fresh. It will create new highways for software applications (and new end-point hardware devices) that will enhance greatly critical communications, both within and between agencies by expanding voice and data communications far beyond what has been seen thus far. This will help agencies think about interoperability far beyond the limited view of “can my radio work on your network?” Instead, agencies will be able to address the broader perspective of interoperability: enabling any user on any device in any organization to communicate with any other user as authorized and operationally beneficial.

Let's now consider the innovative solutions likely to emerge once this new broadband wireless IP network is leveraged. Devices are cool, but cooler still is the software that runs on these devices and brings them to life. When considering software, it would be wise to listen to those who have experience in writing critical communications applications that leverage the natural capabilities and interoperability that IP has to offer — given that it is the most ubiquitous transport protocol on the planet and the one common networking capability shared by virtually every organization.

Shouldn't the next generation of wireless broadband usher in a whole new set of players and applications — technologies that approach unified communications differently and more completely? For example, IP sets the stage for software applications that can unify any combination of existing communications devices – and then get them cruising at new speeds over mobile IP highways made possible by LTE.

Reuven Carlyle, a Washington state representative from the Seattle area, has stated publicly that P25 is too pricey and that public safety would be better off using cell phones. The implication is that modern solutions could see a marriage of new and existing technologies that would benefit everyone. Although Bill Schrier, the city of Seattle's CTO, responded with a list of reasons why this wasn't practical — primarily the need for network priority, reliability and talk-around in urgent communications environments — Carlyle was actually on to something. Let's not forget that the commercial sector has been delivering business-critical voice-over-IP for years, solving priority, latency and many other technical issues along the way. So while LMR has an important place in critical communications, so too will LTE. The latter's applications will extend and supplement LMR, as Carlyle's proposal to leverage smart phones for mission-critical voice suggests.

Many public-safety employees use smart phones for business and wish they had access to cool apps like those they enjoy when using their personal smart phones. While it may not be appropriate or even desirable for an app store to exist that is similar in size to that found in the consumer market, business users should be able to benefit from the same kind of innovation and thought leadership. It is crucial than that developers make available valid, secure, hardened applications that support a broad dimension of critical communications.

In just the next couple of years, the critical communications market will see not only some interesting new mobile devices, but it also will see a wide range of software applications that create and consume many forms of voice, video and data. Situational awareness, monitoring, location tracking, dispatch and other software applications will be greatly enabled by the existence of both private and public LTE networks.

As with the introduction of any new transport network or an influx of bandwidth, there will be increasing discussion as to “what's the killer app for LTE?” In the course of such discussion, one of the most important capabilities of any network will be rediscovered — that is, its ability to enable people to talk to each other. What was the “killer app” when VoIP was introduced? It was voice — real-time communications, people talking to each other. Again, one of the most useful aspects of LTE as a high-speed data-transport network will be its ability to efficiently transmit packets of voice, wirelessly, to any device.

However, voice communications in markets that regularly use radios, intercoms, paging systems and broadcast systems, take on a little different meaning. There has been much progress towards the emulation of circuit-based, i.e., telephone, calls over IP networks, and such point-to-point communications generally are referenced whenever VoIP is discussed. The communications enabled by channels or talk groups in radio systems, however, are not point-to-point. Rather, they are multicast and what is need from IP networks — in addition to supporting point-to-point communications — is the ability to create channels of team communications in a way that is not limited to the device being used or the access network to which each user is connected.

So now the mission-critical world waits for the painfully slow standards process to create a pathway for voice-over-LTE (VoLTE) communications that includes a multicast component. Generally it is understood that this standardization is necessary for the bulk of cellular communications to transition from 2G/3G networks to 4G/LTE. What is not broadly understood, however, is that the software technology to enable critical communications over LTE already exists today — and it does not require that LTE (or any other network) provide “voice” services. All that is required is that LTE quickly and reliably route IP packets.

The real challenge concerns the creation communications channels in IP networks that are always on, accessible only by those authorized and that can be connected to virtually any legacy communications system to achieve interoperability. It's a tough challenge, as multicast in IP “out of the box” isn't reliable and only exists on a subset of private and public networks. There also are no standards currently that broadly define how to accomplish this.

That said, software developers already are working on the challenge, and making inroads. Soon, end-users will see a multitude of products that enable IP talk groups or team communications channels, and which are fully capable of running on LTE networks. Some will be in the form of simple applications on handheld and portable devices. Some will be in the form of dispatch, incident command and control, and situational-awareness products. Others will transmit telemetry and sensor data to those who need it, or focus on video distribution.

Will these new products (software applications combined with hardware) replace LMR someday? Not likely. But it is very likely that these new products will offer alternatives to some end-users who currently carry radios. And it is an absolute certainty that these new capabilities will introduce a new breed of software-powered solutions that go far beyond what LMR systems do today.

Tom Guthrie is the president and CEO of Twisted Pair Solutions.

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