Electronic warfare is a growing threat to forces in Europe.

NATO forces there have taken steps to ward off hacks of their personnel devices, and Russian troops have practiced mitigating electronic attacks on their networks.

NATO has already said that a cyberattack on one member could trigger a collective response.

NATO has beefed up its presence in Eastern Europe over the past two years in response to Russia's incursion in Ukraine.

Multinational battle groups have been deployed to Poland and the Baltic states, and recent NATO exercises have focused on mobility and interoperability — two facets that would be essential to any coordinated military effort.

Those exercises have also included preparations for the increasingly potent threat of cyber warfare.

During Saber Strike, a US-led exercise in early June that saw the 2nd Cavalry Regiment march more than 800 miles from Vilseck in southeast Germany to a training area in southern Lithuania, pieces of enhanced technology were put into use, including small reconnaissance drones and electronic-jamming equipment — the kind of hardware that would be used to block efforts to interfere with operations, electronically or otherwise.

An RQ-7 Shadow drone with the 2nd Cavalry Regiment prepares for catapult launch for an aerial reconnaissance exercise during Saber Strike 18, June 7, 2018. Michigan Army National Guard/Spc. Alan Prince

Around the same time, dozens of NATO ships and aircraft were taking part in this year's iteration of the Baltic Operations exercise in the Baltic Sea, where Russian observers watched closely.

Baltops 18 focused on boosting "our skills within warfare, the anti-air warfare, anti-surface warfare and anti-submarine warfare," Commodore Søren Thinggaard Larsen, the Danish officer in charge of Standing NATO Maritime Group 1, told Defense News this month.

Larsen and other military officers involved said Russian personnel behaved professionally and kept their distance, but the NATO forces were taking new steps to insulate themselves electronically: All members of the crew on Larsen's four ships were required to keep their phones on airplane mode to ward off hacking attempts.

"It is very important that we learn about this new environment, that we learn how to handle it and how to protect ourselves from influence in the cyber area," Larsen said of the restriction, adding that the exercise included specific cyber scenarios.

Cyberattacks are not new, nor are efforts to counter or mitigate them.

The Gabya-class frigate TCS Gediz, right, and the Iver Huitfeldt-class frigate HDMS Niels Joel at sea during Baltops 2018, June 9, 2018. US Navy/Mass Comm. Specialist 3rd Class Jessica L. Dowell

In 2007, crippling cyberattacks paralyzed much of Estonia in what appeared to be a response to a dispute over the movement of a Soviet-era war memorial. While Russia denied responsibility, Western experts suspected Moscow was behind it.

In late 2014 — months after the Russian annexation of Crimea — NATO leaders agreed that a large-scale cyberattack on one member could be considered an attack on the alliance, an expansion of the organization's remit to reflect new threats to critical infrastructure, financial networks, and government operations.

At the beginning of 2017, NATO Secretary General Jens Stoltenberg said the alliance was experiencing an increasing number of state-sponsored cyberattacks — a monthly average of 500, "an increase of 60% compared to 2015," he said.

NATO closed out 2017 by announcing it would boost its own cyber-defense capabilities, adapting its command structure to integrate cyber weapons, a marked shift from its previous defense-only stance.

During Zapad 2017 — the massive military exercise Russia carried out in Belarus in late 2017 — Russia performed electronic-warfare drills on an unprecedented scale.

Belarussian President Alexander Lukashenko awards Russian servicemen during the Zapad 2017 war games near the town of Borisov, Belarus, September 20, 2017. Thomson Reuters

"The amount of jamming of their own troops surprised me. It was at a level we haven't seen," Col. Kaupo Rosin, the chief of Estonia's military intelligence, told Defense News in November. "And they did it in the different branches, so land force, Air Force. That definitely surprised us."

The exercise was meant to practice responses to electronic interference, Rosin said. Russian forces can switch to civilian electronic networks while on their own territory, should military networks become unusable.

"They tested [their own troops] to learn how to switch into their own cable network and not to emanate anymore, but to deal with the problem," Rosin said.

NATO forces in Eastern Europe have been on the receiving end of hacking attacks on their personnel electronics.

US Army Lt. Col. Christopher L'Heureux, at the time a commander of a NATO base in Poland, told The Wall Street Journal last year that someone had tried to get through the password protection on his phone and had been using the device to physically track him.

The US and other militaries have tried to adapt, sometimes with rudimentary methods.

A US Army Space and Missile Defense Agency trainer instructs Ohio Army National Guard soldiers on detecting electromagnetic interference on a GPS receiver, June 23, 2018. US Army/Staff Sgt. Michael Carden

Troops at Estonia's Tapa military base switched to a "no smartphones" policy last year, after they noticed their contacts were disappearing and music they had not downloaded would start playing.

Some officers took the extra step of ordering soldiers to jump in lakes during exercises to make sure they were not carrying their phones. Some soldiers went so far as to wrap their phones in condoms to ward off hostile signals.

US troops have started preparing for potentially debilitating electronic attacks during training exercises in the US.

Ohio National Guard troops drilling in Michigan this month worked with personnel from the US Army Space and Missile Defense Command to identify and mitigate cyberattacks on GPS systems.

"There are adversaries out there with the capability to deny, degrade and disrupt our capabilities," Capt. Kyle Terza, chief of home-station training for USASMDC, said in an Army release. Terza said some younger soldiers had likely never experienced such attacks.

"The threat is out there and, while we may not be facing it right now, if we are looking towards the future, we have to be trained and ready to operate without it," he said.

