Australia was the seventh-biggest target in the world for denial-of-service attacks - the same attacks that led to the census being taken down - over the past day.
US-based Arbor Networks, which operates the ATLAS analysis and monitoring system, reported there were in the past 24 hours 184 DOS attacks on Australian targets, or 3.8 per cent of all attacks internationally.
The United States, South Korea and China were reported as the biggest sources of the attacks.
The figures come as the Australian Bureau of Statistics seeks to bring back online its census form, which was taken down after a series of DOS attacks and the failure of a vital piece of computer hardware known as a router.
Denial-of-service attacks overwhelm a target with either too many connection requests or too much bandwidth.
The result is to make the target inaccessible but often other parts of the system such as routers suffer collateral damage.
