
TOKYO -- The technical failure that interfered with trading on the Tokyo Stock Exchange on Tuesday stemmed from an error in a high-frequency trader's systems and exposed the relative fragility of Japan's stock market infrastructure.
The problem was first spotted by the exchange's systems department around 7:30 Tuesday morning. A large volume of messages -- data swapped between systems when logging in or placing orders, for example -- flooded onto one of the four connections linking brokerages' ordering systems with the bourse's trading servers, sparking fears of cyberterrorism.