How to build a guerrilla communications network
Last weekend, while reading Popular Science, I stumbled on this fascinating article about how the Mexican drug cartel known as The Zetas used ordinary two-way radios and hidden antennas to build a sophisticated intra-national and international communications network that stretched from Guatemala to Arizona, facilitating drug smuggling and money laundering across its entire reach.
The potential for nobler applications in North Korea is obvious. The prerequisite to the rise of any national resistance movement is the creation of a broad-based, grass-roots political organization with a unifying ideology and the capacity to communicate and provide for its members. As you read this – especially those of you who are more tech-savvy than I am – think about how the Zetas’ environment differs from North Korea, and about ways to level those differences. Off-hand, the only one that occurs to me is that Mexico has a crowded radio spectrum, a problem that can be solved by flooding North Korea’s spectrum with decoy signals.
The U.S. nerve center of the Zetas’ network was an inconspicuous little shop on the outskirts of a small border town.
One of those swept up in the net was a 37-year-old resident of McAllen, Texas, named Jose Luis Del Toro Estrada. He seemed, at first, not particularly significant–a luckless guppy caught swimming with sharks. His arrest barely warranted mention in the local paper. His house, a well-maintained white-brick rancher with an arbor of pink flowers over the front door, contained no cocaine or caches of AK-47s. He lacked an extensive rap sheet and in fact seemed to have no criminal record at all. On the outskirts of McAllen, he ran a small, nondescript shop that installed car alarms and sold two-way radios.
In the weeks that followed, a different picture began to emerge. Del Toro Estrada was neither capo nor killer, but he played a critical role in The Company. According to federal prosecutors, the shop owner–who went by the alias Tecnico–had served as The Company’s communications expert. He was the cartel’s in-house geek, the head of IT, and he had used his expertise to help engineer its brutal rise to power. Del Toro Estrada had not only set up secret camera networks to spy on Mexican officials and surveil drug stash houses, but he also built from the ground up an elaborate, covert communications network that covered much of the country. This system enabled the cartel to smuggle narcotics by the ton into the U.S., as well as billions of dollars in drug money back into Mexico. Most remarkably, it had provided The Company with a Gorgon-like omniscience or, according to Pike, the ability to track everything related to its narcotics distribution: drug loads but also Mexican police, military, even U.S. border-patrol agents. That a cartel had begun employing communications experts was likely news to most of law enforcement. That it had pulled off a massive engineering project spanning most of Mexico–and done so largely in secret–was unparalleled in the annals of criminal enterprise.
The Zetas rejected cell phones in favor of old-fashioned two-way radio.
It’s impossible to say exactly why the Zetas chose to build the radio network, but given their military and law-enforcement background, it seems likely that Z1 and his capos understood that a widespread communications system would provide a crucial competitive edge over other cartels. Radio was the clear choice. Unlike cell phones, which are expensive, traceable, and easily tapped, radio equipment is cheap, easy to set up, and more secure. Handheld walkie-talkies, antennas, and signal repeaters to boost transmissions are all available at a good radio shop or from a Motorola distributor. A radio network could provide communications in many of the remote areas in Mexico where the cartel operated. And, if they suspected law enforcement eavesdropping, the cartel’s drug smugglers and gunmen could easily switch frequencies or use commercially available software to garble voice transmissions.
It’s not clear to me why radio was “a clear choice.” After all, cell phones use a radio signal, too. (Maybe someone can explain this.) But the network had enormous utility to the Zetas.
How Jose Luis Del Toro Estrada was tapped to develop the covert radio network also remains a mystery, but as his system grew, it supplied the Zetas with what’s called a command-and-control capacity. “It essentially linked all the different members of the cartel–the people doing the trafficking and the people doing the protection–so there was a communication between them,” says Pike, the DEA special agent. Armed with handheld radios, the cartel’s street-corner halcones, or hawks, could help commanders avoid arrest by alerting them whenever police set up checkpoints. A midlevel boss in Nuevo Laredo could monitor a semitruck carrying several tons of cocaine as it trundled across the border into Texas. Most crucially, Zetas gunmen could use the system to attack and seize plazas, or smuggling corridors, held by other drug gangs.
“With a network like this, you can take what resources you have and maximize them for effectiveness,” says Bunker. “If [the Zetas] are going into a different cartel’s area, they can bring resources in,” such as weapons, vehicles, and reinforcements. “It means for every one enforcer or foot soldier, you get a multiplier effect. From a command-and-control perspective, it’s phenomenal.”
The network wasn’t just an advantage over the police, but also over rival gangs, which the Zetas proceeded to exterminate. Ironically, one of the businesses that the Zetas went into was DVD smuggling (like drug smuggling, it’s also a big business along the Sino-Korean border).
In any new city where the cartel wished to expand, Del Toro Estrada’s first step would have been to map the local radio spectrum. Identifying who operated on what frequencies and which had the lightest traffic would preclude, for example, a local taxi company’s radio chatter from disrupting a coordinated attack on a police station. In urban areas, Del Toro Estrada often affixed a cartel antenna to an existing commercial radio tower. He also hijacked radio repeaters–devices that receive and boost radio signals–from companies like Nextel and reprogrammed the equipment to use the cartel’s preselected, low-volume frequencies. (Nextel maintains both cellular and, for its push-to-talk phones, radio networks). In at least one location, Del Toro Estrada installed a repeater on the roof of a Mexican police station, either a brazen display of the cartel’s impunity or a signal of the department’s corruption.
Expanding into more remote areas, like the jungle in southern Veracruz state, was more technically challenging: Towers had to be built atop high vantage points–a volcano’s summit, for example–to ensure surrounding hills or other natural obstacles didn’t block transmissions. Del Toro Estrada then installed repeaters and antennas on top of the tower, and in some instances, the structure was painted a dark green to camouflage it amid the foliage. To provide power, he wired the equipment to car batteries or, in many cases, photovoltaic solar panels. In Veracruz, a string of about a dozen tower installations provided a 100-mile radius of communications capability–meaning the Zetas could track anything that moved, whether encroaching Sinaloa cartel gunmen or military convoys, in at least 10 towns and cities.
“It was just a constant flow of information,” Pike says. “I equate it to the scene in Black Hawk Down when the chopper’s taking off from the military base and the child up on the mountain with the telephone calls down and says, ‘They’re coming.’”
As subnetworks went live in new areas, Del Toro Estrada daisy-chained them together into a larger, interoperable system. This ability to link different units of the cartel was the network’s strength, more than anything else. With commercial software from companies like Motorola, he could remotely manage thousands of walkie-talkies at one time. If a frequency in one area became too congested, he could switch users’ radios to another. If a local boss in Matamoros had to coordinate a drug load with someone in Monterrey, Del Toro Estrada could connect them. If Zetas were captured, he could disable their handsets to thwart eavesdroppers. He also used digital inversion software, which scrambles radio transmissions into garbled, R2-D2–like squawking. The cartel even established regional command centers to manage some of its communications. In Coahuila state, Mexican soldiers raided a Zetas-occupied home that contained networked laptops, 63 digital walkie-talkies, a central processing unit to remotely control repeaters, and a digital radio that communicated with airplanes.
The Zetas invested significant resources in maintaining, expanding, and exploiting the network:
By 2008, Del Toro Estrada’s infrastructure was operational in most states in Mexico (and likely in the U.S. borderlands as well). Local bosses chipped in for equipment, and the Zetas maintained ledgers detailing outlays for communications gear. Del Toro Estrada himself employed a team of specialists–his own cartel Geek Squad–to research new technology and program equipment. The network’s architecture, like the nodes of routers that undergird the Internet, was resilient: If the Mexican military knocked out one tower, traffic could likely be routed through another. And it was, relatively speaking, cheap: The Company probably spent tens of millions of dollars building the network–a capital investment that would have paid for itself with the delivery of one large cocaine shipment into the U.S.
“This thing was huge,” the former official says of the cartel’s communications system. “It was extensive, and it was interconnected. It was the most sophisticated radio network we’d ever encountered.” [….]
With the Zetas at the center of the violence, the Mexican military decided to strike back at their most valuable asset: the radio network. Battalions of troops were dispatched, and the military began attacking the system, probably aided by DEA-supplied intelligence directly from Del Toro Estrada, who began cooperating with the agency after his arrest and provided information about the system’s infrastructure. During one operation in 2011, Mexican marines discovered several 18-wheelers housing mobile communications systems in Veracruz. Another operation spanned four states and resulted in an astonishing haul: 167 antennas, 155 repeaters, 71 computers, 166 solar panels and batteries, and nearly 3,000 radios and Nextel push-to-talk phones. Later, marines discovered a 300-foot-tall antenna tower by a major highway.
With the help of their radio network, the Zetas made parts of Mexico ungovernable. Given North Korea’s almost roadless interior, the decrepit state of its railways, and the small size of its helicopter force, one wonders how hard it would be for a political opposition – particularly one that supplied the local population with food, medical care, and essential services – to take root, and eventually, to disrupt state control. A network like this wouldn’t have to fire a shot to put an enormous strain on North Korea’s security forces, and impose a potentially crippling financial cost on the state.
The article is interesting in other ways, such as how the Zetas managed to corrupt police, soldiers, and ordinary citizens to serve as spies or soldiers in its network. Of course, North Korea is a state built around internal control, and it’s specifically designed to defend against just this sort of subversion. But a movement that can provide for the most vulnerable elements of the population always has the potential to take root, and to expand its reach to the lower rungs of North Korea’s songbun system.