TALLINN, Estonia – Eleven Airmen from the Maryland Air National Guard’s 175th Cyberspace Operations Group participated in Locked Shields 2025, an international defensive cybersecurity exercise designed to allow cyber experts to enhance skills in defending critical infrastructure from potential cyberattacks.
The 15th annual exercise, held April 27-May 10 and hosted by the NATO Cooperative Cyber Defense Centre of Excellence in the Estonian capital, brought together 41 nations and included more than 4,000 people who attended in-person and remotely. Maryland sent cyber operators from the 175th Cyberspace Operations Squadron, the 276th Cyberspace Operations Squadron and the 275th Operations Support Squadron.
“This exercise fostered interaction between our Airmen and military members from other nations, to build a shared understanding of the global threat landscape. Through these discussions, we identified commonalities and distinctions in how different countries perceive these threats, compared to the U.S. perspective.” said Maryland Air National Guard Lt. Col. Bob DeLuca, flight commander of the 175th Cyberspace Operations Squadron.
The exercise involved familiarization with the cyber range during the first week to prepare and learn what infrastructure will be involved in the main portion of the exercise.
“This year, our team had to defend over 8,000 systems from attacks from the Red Team. This year’s range types included simulated military infrastructure, telecom networks, Supervisory Control and Data Acquisition-based systems, industrial control systems, governmental networks, 5G infrastructure and a water treatment facility. Every year, the range gets more complex and challenging for blue teams to manage,” DeLuca said. “During the exercise, teams were scored on a comprehensive system, including the team’s success in preventing the attacks, system availability, incident reporting and collaboration, as well as parallel legal, strategy and strategic communication tracks.”
Maryland Air National Guardsmen augmented the Estonian, Lithuanian and Montenegrin blue teams, which included more than 450 people. Members collaborated virtually with participants from all over the world, including the Virginia National Guard, the Maine National Guard, Montenegro, Lithuania, Ukraine and Estonia. The exercise consisted of 17 blue teams and one offensive red team.
“Our successful collaboration with the Estonian team highlights the strength of our 30-year State Partnership Program relationship. Their assistance has been invaluable as we work collaboratively to solve joint problems,” DeLuca said. “Working directly with our Estonian partners is incredibly valuable. It helps us gain a deeper understanding of their approach to cyber defensive missions.”
The Maryland National Guard has partnered with Estonia via the Department of Defense National Guard Bureau’s State Partnership Program since 1993. The exercise allowed senior leadership and junior enlisted Airmen to foster and connect through this long-standing relationship.
“To expand our group’s capabilities and facilitate knowledge exchange, I ensure a mix of experienced and new Airmen participate in these events,” DeLuca said. “Looking ahead, we aim to enhance the collaboration between the Maryland and Virginia Guard. This preparation is crucial as we strive to be as capable a partner with the Estonian and Finnish teams for Locked Shields 2026.”
Two Virginia Air National Guard members attended this year to observe the exercise in preparation for their participation next year. The Maryland Air National Guard hopes to incorporate joint training with the Virginia Air National Guard, which hopes to engage in next year’s exercise with their state partner Finland.
“We all were working together to figure out how to attack the problem at hand, and we definitely benefited from working with our Estonian coordinators,” said Maryland Air National Guard Senior Airman Seth Atangcho, systems operations specialist for the 175th Cyber Operations Squadron and first-time attendee of Locked Shields 2025. “In one situation, the Estonians assisted us with developing a script to create alerts and keep track of the tickets we were being assigned. Then a member of our leadership was able to build on it and create a more robust program to organize relevant information among the alerts that we received.”
Navigating new territories and systems, participants expanded their knowledge through multinational teamwork that encouraged joint, worldwide collaboration.
“Our Guardsmen did an excellent job, quickly integrating and excelling in their assigned areas,” DeLuca said. “They were crucial to their teams’ success.”