Imminent Domain

By Admiral Jonathan W. Greenert, U.S. Navy

But our military concepts, acquisition, tactics, and training have not coherently or fully embraced the central role of the EM spectrum and computer networks in our operations. In many ways we still treat the EM-cyber environment as a tool or means to support operations in the physical domains of sea, air, or land. The EM-cyber environment is now so fundamental to military operations and so critical to our national interests that we must start treating it as a warfighting domain on par with—or perhaps even more important than—land, sea, air, and space. Future wars will not be won simply by effectively using the EM spectrum and cyberspace; they will be won within the EM-cyber domain. Achieving that change and commanding the EM-cyber environment require innovative operating concepts, new military systems, and most important, a fresh approach in thinking about modern warfare.

From Military Tool to Warfighting Domain

Humans have used the electromagnetic spectrum for about a century to communicate and monitor their surroundings. German scientist Heinrich Hertz proved the existence of electromagnetic waves in 1888; Guglielmo Marconi first harnessed them for communication in 1895 with his primitive radio set in Italy. Military research into EM technology began almost immediately, but it was not until 1920s that the first militarily useful applications appeared. The Naval Research Laboratory (NRL) developed high-frequency radios for ships, and in 1922 NRL scientists first detected a moving ship using radio waves, marking the first use of radio detection and ranging—radar. In 1939, the Navy installed the first shipboard radar in the battleship USS New York (BB-34), and the new technology paid off almost immediately in World War II.

Additional applications of EM technology followed, but the pace of development depended on emerging computer technology to process, remember, display, and disseminate information. After World War II, NRL developed the identification, friend or foe (IFF) equipment used today on board all military and civilian aircraft to aid air-traffic control. With the advent of the Space Age in the 1960s, NRL researchers began the TIMATION program, which envisioned the use of satellites for terrestrial navigation. As computer processing advanced, that program evolved into the GPS currently used by everything from precision weapons (smart bombs) to navigation systems in civilian vehicles.

Radars also benefited from computer technology and now do much more than simply bounce EM energy off objects to detect them. Information-processing enables radars to recognize extremely faint returns from background clutter to detect small objects—say, submarine periscopes—and to automatically and reliably track moving targets such as people, small boats, and trucks. Radars use computer processing to classify ships and aircraft by type, and to identify specific points on targets to place precision weapons. Jammers that once simply overloaded radar or communication receivers with EM energy can now use computer controllers to deny signals to receivers or retransmit altered signals to them that inject false targets, obscured areas, or even malicious computer code. Our newest radars and jammers can also coordinate and synchronize their operations automatically with one another through computer networks, even when the systems are on different ships, aircraft, or unmanned vehicles.

At the same time that military EM systems adopted computer technology, military cyberspace increasingly used the EM spectrum. During Operation Desert Storm in 1991, terrestrial wireless networks were slow, and higher-speed satellite systems were reserved for only the most important operations. Real-time networking still depended on a cable. Today, the EM spectrum is part of almost every military computer network around the world, dramatically increasing the flexibility of operations. That creates military opportunities, as well as vulnerabilities. We can use the EM spectrum to access an adversary’s computer networks—but adversaries potentially can do the same to U.S. forces.

Parallels in History

Our effort to create the systems, procedures, culture, and institutions to command the EM-cyber environment parallels our previous experience in acoustics and undersea warfare. EM technology emerged at the turn of the 20th century—around the same time submarine advancements made the undersea domain militarily relevant. Initially, we used that new realm sparingly. In World War I, submarines remained on the surface most of the time, submerging only to get into final attack position, then often resurfacing to attack with torpedoes and guns. By World War II submarines were spending more time staying below the surface to maneuver, attack, and evade counterattack. Submarines still transited on the surface, however, and submariners were only beginning to understand acoustics and the characteristics of the undersea environment.

By the Cold War, U.S. submarines spent almost all their time submerged. With the experience of “living in the domain” we developed doctrine, systems, and an understanding of how to employ undersea acoustics to detect enemy submarines while avoiding detection by surface ships. That provided a distinct advantage in the long competition with the Soviet Union, but one that would prove challenging to maintain. As the Soviets gained experience, they also improved their understanding of undersea acoustics and their capability to detect and threaten U.S. submarines.

Cold War submariners and designers had to contend with the vulnerability of self noise and acoustic emissions, continually managing their sound signature to avoid detection or classification by potential adversaries. This understanding inculcated submarine operations and procedure with a culture of acoustic silencing that dramatically reduced submarine detectability, which continues to benefit our submarine force. Today we command the undersea environment. A similar culture of EM silencing and understanding of electronic signatures will have to permeate our efforts if we are to command the EM-cyber environment.

Commanding the EM-Cyber Environment

Today we generally use the EM spectrum and cyberspace as an enabler for land, sea, air, and undersea operations. We have not yet taken full advantage of the warfighting potential afforded by the merging of the EM spectrum and cyberspace, or the pervasiveness of the EM spectrum into every facet of military operations. We have a wide range of EM capabilities such as the E/A-18G Growler electronic attack and E-2D Hawkeye early warning aircraft, SPY-1 radar on our Aegis surface ships, and a growing number of electronic warfare and cyber systems. Those capabilities, however, are still operated in large part by specialists in the context of specific missions.

To command this new environment, EM-cyber operations will need to become an inherent element of how we operate and fight in every situation, all the time. America’s key military advantage for the past 20 years has been its ability to sense and create a picture of our surroundings and use that picture to control the air, sea, and undersea domains. The radars, satellite communications, and command-and-control systems we use have performed well in relatively benign and uncluttered environments, as we have seen in the wars in Iraq and Afghanistan. That will not be the case in future conflicts.

Inexpensive jammers, signal detectors, computer processors, and communication systems make it easier today for unfriendly states, terrorists, and criminals to affect our ability to use the EM-cyber environment. Meanwhile, the number of users in the EM spectrum has grown dramatically over the past two decades. That growth and the challenges in managing it combine to create a spectrum that we struggle to sense, understand, and command. Our dependency on the spectrum and computer networks could become an Achilles’ heel—for us as well as our adversaries. We must therefore make a concerted effort to harness them to our advantage. That will require a deliberate approach.

Know the Environment

First, we must establish our awareness of the EM-cyber environment. Sailors depend on information about the weather, air and ship traffic, and oceanography to choose courses at sea. In war, our operators must know where noncombatants (or “white” shipping) are so they can avoid collateral damage. The same holds true for operations in the EM-cyber environment. We need to detect, assess,and predict in real time the activities going on in that domain and use that knowledge to guide our own EM-cyber operations. Building that level of awareness will be challenging. Today we understand how weather, geography, and other EM emissions can affect EM signals, and we are developing improved techniques to identify computer-network anomalies that may indicate threats or potential threats. But our tools for collecting and analyzing information in the EM-cyber environment are limited, and we lack the familiarity and understanding to take full advantage of what information we do have—often learning only in retrospect what happened in a particular jamming, communication, or cyber event and why it occurred.

To build better tools for sensing the EM-cyber realm, we must turn to and partner with commercial industry. While the military created the first operationally relevant EM-cyber systems, today consumer and business electronics drive EM and cyber innovation and technology. For example, high-bandwidth devices such as 4G smart phones require sophisticated signal monitoring to adjust their transmission characteristics and remain connected to the network. Similarly, terrestrial and satellite broadcasters require high-fidelity sensing of the EM and meteorological environment, while computer-network administrators have to continuously monitor and understand the condition of their system and where data are moving or not moving.

We can use commercial sensing-technologies and know-how to create a common operational picture for the EM-cyber environment as we do today in the air or maritime domains. We will combine those systems with predictive modeling to allow us to better understand what the EM-cyber common operational picture is telling us, and what may happen next. For example, we are building systems to monitor activity on our networks to establish what “normal” looks like, allowing us to distinguish friend from foe and identify changes that could indicate an attack or system failure.

Be Agile

Second, we will employ agility in the EM spectrum and cyberspace to reduce our vulnerability to detection and exploitation and to maximize our ability to defeat jamming and deception. The need for agility will introduce new principles for developing Navy EM-cyber systems. Our most successful radars, for example, employ extremely high power with a well-defined set of characteristics. The AWG-9 radar in the original F-14 Tomcat made it a successful interceptor capable of engagements at extended range, while our high-powered SPY-1 series of radars allows our cruisers and destroyers to engage ballistic missiles outside Earth’s atmosphere. Those radars, however, are highly detectable and easy to classify. If our systems instead could shift frequency over a wide range, use shorter-burst transmissions, employ small directional beams, or move applications between servers automatically in response to a sensed anomaly, our EM-cyber operations would be less predictable, harder to classify, and more difficult to counter or disrupt.

But the characteristics of our current radars, radios, and electronic-warfare systems are, for the most part, hard-wired in the form of physical-wave guides, arrays, and processors. To improve our agility we need to accelerate our shift to EM-cyber systems with software-controlled characteristics and hardware that is modular and can be quickly and inexpensively changed to operate with different EM parameters. Our Integrated Topside (INTOP) project is one way we are beginning to improve our EM agility. Instead of using different antennae for each different radio, radar, or receiver, INTOP uses modular, reconfigurable antennae that can be employed in any of those applications. We are also expanding the use of offboard EM systems on unmanned vehicles, for example, to reduce the vulnerability of our platforms to counterdetection and take advantage of the ability of those payloads to evolve more quickly over time than their host ship or aircraft.

EM-cyber agility also will improve our ability to deconflict the growing number of military and civilian EM-cyber systems. Here we also can take advantage of commercial innovations. For example, our Link-16 datalink uses a filter to prevent interference with other aviation EM systems, such as approach radars and landing-assist systems. As more EM systems are fielded, a simple filter will not be enough; systems such as Link-16 may have to time-share frequency bands with other users, similar to the way mobile phones and wireless computers sense the spectrum and automatically adjust to avoid interference.

Change Our Paradigm

New technology for agility and awareness will not, by itself, enable us to command the EM-cyber environment. We must also change our paradigm to treat it as a primary warfighting domain. That is our third and most challenging initiative. Wars increasingly will be fought in the EM spectrum and cyberspace, so we cannot treat EM-cyber capabilities as simply enablers for air, land, and space operations. Our Air-Sea Battle concept, for example, describes tightly orchestrated operations between the EM-cyber environment and the air and maritime domains to defeat threats to access, such as antiship cruise missiles and submarines. But our current means of managing military operations are neither structured nor adaptable enough to rapidly authorize and approve an EM or cyber operation in the same manner that they can direct a bomb or missile attack. We generally plan and coordinate EM-cyber operations in advance of the mission. To achieve the high level of coordination the future will demand, we will change our doctrine and command-and-control organization to plan and coordinate operations in the EM-cyber environment in “real time” alongside air, land, and maritime operations.

In concepts such as Air-Sea Battle, EM-cyber operations are used to attack an adversary’s whole kill chain—preventing enemies from seeing or accurately tracking our forces, denying their ability to communicate targeting information, and decoying or diverting weapons that approach our forces. We will expand the use of EM-cyber “training ranges” to gain proficiency in conducting these operations and broaden education on the EM-cyber environment beyond today’s cadre of specialists. Our curricula—from boot camp to the Naval War College—will include EM-cyber warfare, just as every sailor today learns something about air warfare, surface warfare, and undersea warfare.

In conjunction with doctrine, organization, and training, we must hold leaders accountable for managing EM-cyber systems as we would any other weapon system. For example, our acquisition community will have to consider EM-cyber implications and vulnerabilities in developing new systems and upgrading existing systems. Commanding officers will need to maintain and employ their EM-cyber systems to the same degree as their missile launchers, sonars, torpedoes, and guns.

Our effort to change the Navy’s paradigm to treat the EM-cyber environment as a primary warfighting domain will take time and focus, but we have a significant base of experience on which to draw—thousands of communications, radar, and electronic warfare specialists and more than 4,000 officer and enlisted cyber operators. We will use their knowledge to train the rest of the force, much as we built EM-spectrum expertise in the U.S. Army during the past decade. Faced with losses from radio-controlled improvised explosive devices (RCIED) in Iraq, the Army asked the Navy for assistance in fielding and operating counter-RCIED electronic warfare (CREW) systems. More than 700 sailors, led by electronic-warfare officers and technicians, deployed to Iraq from 2006 to 2011 as part of Joint CREW Composite Squadron 1. That group helped defeat the RCIED threat and built a broad understanding in Army units of operating and employing systems in the EM spectrum, as well as the vulnerabilities of our troops to adversary EM operations.

We find ourselves at the advent of a new era, similar to the mid-20th century when we saw that the undersea domain could provide a significant advantage over our potential adversaries. Unlike that realm, however, the EM-cyber environment is filled with individual, commercial, and military users. The vast number of users makes more new technology available to us—but also to competitors and potential adversaries. To seize the high ground in this new domain, we need to fundamentally change our approach to operations and warfare. To do that we will bring to bear those strengths that are impossible to reverse-engineer—the expertise and flexibility of our research base, our history of adaptation, and the skill and perseverance of our sailors.

Admiral Greenert is Chief of Naval Operations.


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