The NZX suffered trading halts last week and disruption yesterday for a fifth day, after denial of service attacks took its website offline.
Andrew Little, the Minister overseeing the country's spy agency GCSB, says despite investigations, it is not known where the attackers are based or what their motives were.
Dr Lech Janczewski is a data security expert at the University of Auckland.
He speaks to Susie Ferguson.
