The National Broadband Network (NBN) could prove to be a best friend to cyber criminals, according to the head of the Australia's National Computer Emergency Response Team (AusCERT).

Speaking at a cyber security roundtable in Sydney, Graham Ingram, general manager at AusCERT said cyber criminals currently placed a premium on infecting PCs which were connected to high-speed networks.

“We have seen cyber criminals reject using dial-up based computers because they aren’t fast enough,” he said.

Anecdotally, the penetration of malicious activity had become almost directly proportional to broadband connectivity speed, Ingram said.

“The same compromised PCs in homes we have now will be the same ones connecting to a faster communications channel via the NBN,” he said. “This will simply amplify the problems we have now significantly.”

Also speaking at the roundtable, chief research officer at F-Secure Mikko Hypponen said connection speed had a decisive role in the selection of PCs for denial of service attacks and spamming botnets.

“We have seen malware which when it infects a PC, the first thing it does is connect to a university file server to download a gigabyte size Linux installation DVD package to clock the speed. If it is too slow it just rejects the PC. [Hackers] have so many machines at their disposal they can choose to be picky.”

Another implication of the NBN was that it was likely to be leveraged for VoIP services, which were increasingly being used in phishing and other cyber security attacks, Ingram said.