Cybersecurity coach Dr Frank Stajano
Computer hackers are constantly exploiting security flaws and accessing private information. For the participants at a new annual competition, though, it's not a crime - it's a sport.
Blood-curdling cries were punctuated by the sound of bamboo swords thwacking against armour, as Cambridge University's Kendo team practiced for their annual match against arch rivals Oxford.
The samurai-inspired martial art requires skill in both attack and defence, and according to the team instructor Dr Frank Stajano, cyber-security is no different.
Video Journalist: Chris Vallance.