Ship Data Interruption Hints at China’s Military Doctrine

December 3, 2021 Updated: December 12, 2021


China’s recent interference with ship-data broadcasts might provide a clue on Chinese military strategy, as well as give a preview of the opening moments of a future attack on Taiwan.

In late October, international ship tracking services noticed a sudden decrease in ship data from Chinese ground stations. These land-based stations receive the Automatic Identification System (AIS) data that nearby ships broadcast. The stations normally relay this information, including the ship’s name, speed, weight, origin, and destination, to tracking services such as MarineTraffic or VesselFinder.

Although the ships (including Chinese ships) continued to broadcast their AIS data, Chinese land stations stopped forwarding that data. This interruption was very unusual, since AIS is a global system that provides real-time data on ship movements to prevent collisions, aid in search-and-rescue missions, and help with port planning. The International Maritime Organization requires AIS data broadcasting by all ships weighing more than 300 tons and all passenger ships regardless of size.

The data are relied upon by shipping companies, ports, banks, insurance companies, and law enforcement.

China’s interruption of land-based AIS receiver data hasn’t made ships disappear. It’s just made tracking them more difficult and less accurate.

AIS signals are also received by satellites, though the satellite data are much less precise. In crowded seas such as those off of the Chinese coast, many hundreds of ships are broadcasting AIS data from a very small area, making for poor quality tracking by satellites.

Since this land-station data blackout came without any warning from China, it was left to industry experts to speculate about the cause.

In press coverage, the blame has largely fallen on China’s new data security law and personal information protection law. These new laws restrict foreign access to data that could compromise Chinese national security or infrastructure. Chinese port operators seem to have interpreted these new rules to mean that sharing ship location information is now forbidden.

The Chinese government hasn’t released any official statement about the matter. But according to an article in China’s state-controlled Global Times, China never intended any disruption in the AIS system, and any interruptions were due to decisions made by local data providers.

But is that really what happened?

It’s interesting to note that this isn’t the first time that the Chinese regime has tampered with the international AIS tracking system.

The nonprofit Global Fishing Watch has documented many irregularities in Chinese broadcasts of location data, including systematic manipulation of GPS data at Chinese oil terminals and government installations, as well as many instances of fishing fleets misreporting their positions.

A 2019 report (pdf) by SkyTruth, an environmental nonprofit, found that Chinese ports are using some kind of distortion field which falsifies nearby ships’ AIS data, including their GPS positions, speeds, and locations. When ships enter the distortion area, their true positions are no longer available. This has been documented at more than 20 locations in six Chinese port cities.

Another investigation (pdf), this one undertaken by nonprofit Center for Advanced Defence Studies, found that the AIS signals from hundreds of ships near Shanghai were showing false locations, including on land.

Global Fishing Watch’s Sarah Bladen said the reasons for all of this manipulation are still unclear.

“We are still assessing China’s decision to block public access to their AIS data,” Bladen told The Epoch Times. “What we can say is that AIS position falsification occurs in a tiny fraction of the global AIS broadcasting fleet and these cases can be readily picked out with automated data analysis for further investigation.”

About China’s fishing fleet, Bladen said AIS falsification isn’t necessarily associated with criminality.

“Chinese flagged vessels account for a large proportion of the global fishing fleet which we track on AIS,” she said. “Some of these Chinese fishing vessels have been found to be broadcasting coordinates with a constant offset from their true location. However, we are uncertain of their motivation for hiding their true location, and we have not linked them to illegal activity.”

Given the long history of China’s manipulation of these tracking systems, it’s unlikely that a misunderstanding over a new law is the reason for the AIS data blackout. There’s another possibility, one that lies not in new laws, but in very old ideas about the art of war and the importance of cyber warfare in the strategy of the People’s Liberation Army (PLA).

One of the principles of Chinese military doctrine is the control of information, which PLA Maj. Gen. Dai Qingmin described in 2002 as “the destruction and control of the enemy’s information infrastructure and strategic lifeblood, selecting key enemy targets, and launching effective network-electronic attacks.”

Col. Larry Wortzel, discussing Chinese war strategy for the U.S. Army War College, wrote (pdf), “The PLA’s warfighting concepts for employing signals intelligence and electronic warfare have expanded to include cyber warfare, attacks on satellites, and information confrontation operations.”

Manipulation of GPS and AIS systems sounds very much in line with Chinese doctrine.

“For the PLA, information warfare is directed at the enemy’s information detection sources, information channels, and information-processing and decision-making systems,” Wortzel said. “The goals are information superiority, disruption of the enemy information control capabilities, and maintaining one’s own information systems and capabilities.”

How might this play out in a war?

“Cyberattacks or the use of electromagnetic pulse (EMP) weapons might precede precision-strike kinetic weapons,” Wortzel said. “For the PLA, the information and communication networks of engaged forces are the focal point for the conduct of military operations.”

Considering this aspect of Chinese military doctrine, an alternate explanation for AIS signal manipulation emerges: In any potential invasion of Taiwan, control of commercial ship data may be absolutely essential. In a waterway as busy as the Strait of Taiwan, which is crowded with hundreds of ships broadcasting their data through the global AIS system, control of information will necessarily be the first step.

Without first suppressing or manipulating AIS data, the world would easily watch a Chinese invasion fleet assemble, load, and depart for Taiwan. Anyone with an internet connection could observe the closure of Chinese ports, the rerouting of commercial traffic, and the unusual movements of vessels in the area. A fully functioning global AIS system would allow plenty of time for detection—and for foreign intervention. China’s unexplained, and so far benign, manipulations of GPS and AIS data may be part of a long-term plan to expand its capabilities in these areas.

Views expressed in this article are the opinions of the author and do not necessarily reflect the views of The Epoch Times.

Lorenzo Puertas
Freelance Reporter
Lorenzo Puertas is a freelance reporter covering China-related topics for The Epoch Times. He is a long-time student of Chinese history and culture, with a degree in traditional Chinese medicine, and a degree in philosophy from the University of California, Berkeley.