The US National Security Agency (NSA) is embarking on a secret domestic surveillance project dubbed "Perfect Citizen", intended to monitor and protect important national infrastructure such as power grids and transport systems.

The Wall Street Journal, citing unnamed government and industry sources, says that the NSA has awarded a "black" (classified) $100m contract to defence contractor Raytheon which will see secret monitoring equipment installed within US networks deemed to be of national importance.

According to the WSJ, Perfect Citizen has caused some disquiet among those in the know. It could be seen as the NSA - a military combat support agency whose focus is supposed to be on external threats - carrying out massive automated surveillance of American companies and citizens. The paper quotes an internal Raytheon email as saying that "Perfect Citizen is Big Brother".

The stated purpose of the project is to get a clear idea of the level of threat facing American infrastructure IT. Many older systems, designed in the pre-network world, have since been hooked up to the internet for ease of use and maintenance. It is feared by some in the US intelligence/defence community that unfriendly powers and organisations are already engaged in probing these systems with a view to learning how to attack them.

The NSA's Perfect Citizen equipment would be designed to flag up unusual network events indicating an impending cyber attack, according to the WSJ's sources.

"You've got to instrument the network to know what's going on, so you have situational awareness to take action," an unnamed military source told the paper.

Many of the networks that the NSA would wish to place Perfect Citizen equipment on are privately owned, however, and some could also potentially carry information offering scope for "mission creep" outside an infrastructure-security context. For instance, full access to power company systems might allow the NSA to work out whether anyone was at home at a given address. Transport and telecoms information would also make for a potential bonanza for intrusive monitoring.

The full scope of the project remains to be determined, according to the WSJ report, with no certainty as yet on which companies or types of companies would be asked to cooperate - or how much information the NSA would get access to.

The NSA - whose boss has now also been confirmed as head of the Pentagon's uniformed Cyber Command - apparently got the job by default, as it is considered the only US agency with enough network and cyber savvy to take the task on.

The Reg has contacted Raytheon and the NSA for comment on Perfect Citizen, but thus far has not received any reply. ®