The U.S. Navy, owner of one of the largest and most sophisticated computer networks on Earth, will turn some of its sailors into ethical hackers to better defend it.

In a solicitation posted last week, the Navy outlined its requirements for training and graduation from the Certified Ethical Hacker program, an intensive five-day course administered from June 6-10 in San Diego, California.

The training must be administered by the International Council of Electronic Commerce Consultants or an authorized partner, and will be provided to 34 sailors. The U.S. Army also pursues similar training for its cybersecurity professionals.

According to the Navy, a certified ethical hacker “is a skilled professional who understands and knows how to look for the weaknesses and vulnerabilities in networks and/or computer systems and uses the same knowledge and tools as a malicious hacker upon request from an organization. The certification is for individuals who are responsible for securing (or testing the security of) computer networks.”

This includes security officers, auditors, security professionals, site administrators and others with a stake in defending the Navy’s IT infrastructure at home, abroad or at sea.

The course itself consists of a combination of lectures, team activities and case studies followed beyond-site certification testing.

Amid increasing threats from nation states and hackers, the military and the intelligence community have struggled to attract and retain cybersecurity professionals in recent years.

Even internal training isn’t a guarantee to retaining employees. Earlier in 2016, one of the Air Force’s top tech officials bemoaned its IT workforce shortage, explaining why it would prefer to outsource IT work than continue training a revolving door of airmen.