Cyber Coalition 21, one of the world’s largest annual exercises in cyber defence, recently concluded in Tallinn, Estonia. Cyber defenders from all NATO Allies, as well as partners Finland, Ireland, Sweden and Switzerland, took part, alongside participants from industry and academia. Overall, some 1,000 people trained in this year’s event, in Estonia as well as remotely, from national capitals and other locations.

The exercise, which has been held annually since 2008, brings together a cyber coalition of NATO Bodies, NATO Allies, and Partners to strengthen the Alliance ability to deter, defend against, and counter threats in and through cyberspace in support of NATO’s core tasks by exercising collaboration and cyberspace operations, and providing input to NATO transformation.

The exercise tests and trains cyber experts in their ability to defend NATO and national networks. From defending against malware, through hybrid attacks involving social media, to hacks on mobile devices, the exercise has a set of challenging, realistic scenarios. This year’s scenarios included a cyber attack on gas supply pipelines; a cyber attack disrupting the deployment of troops and logistics; and a pandemic-related ransomware attack, where vaccine data is stolen and vaccination programmes are compromised.

The Cyber Coalition exercise is executed through the Estonian Cyber Security Exercises and Training Centre, or 'CR14', Tallinn's latest cyber range supporting NATO Allies and Partners. Training audience and local trainers participate from their respective Nations and entities through virtual networks, and a small exercise control group assembles in Estonia to execute the exercise.

The players do not compete, but collaborate, exchanging first-hand information, experience and best practices in handling cyber incidents. By working together, the individual participants, as well as their organisations, nations and NATO, enhance their cyber resilience.

For NATO, Cyber Coalition 21 is a means to improve the organisation’s own Information Technology network protections and fine-tune its mechanisms for real-time information exchange with Allies and partners. The exercise is also an important test of the organisation’s ability to conduct operations in cyber space, and to deter and defend against threats in the cyber domain.