The government's clean feed Internet scheme has been buoyed by glowing results from tests into the effectiveness of Internet Service Provider (ISP) content filters.

The Australian Communications and Media Authority's (ACMA) Internet content filtering report, the latest of a series that was first commissioned in 1993, claims the technology has undergone massive improvements since 2005 when that year's trial returned abysmal results.

ISP content filtering is part of the government's $125.8 million Plan for Cyber Safety which will split funds between law enforcement, technology and education to reduce the proliferation of child porn and inappropriate content.

Communications Minister Stephen Conroy said the government will soon trial blocking prohibited and "additional" material in a live pilot with ISPs using the filters.

"The next step is to test filter technologies in a real world environment with a number of ISPs and internet users," Conroy said.

"Filtering specifically against a black-list of illegal content as well as the ability to filter additional material will be one part of the upcoming pilot trial.

"This will enable the implementation of ISP filtering in Australia to be undertaken in an informed and effective way."

The ACMA test of six Internet content filters showed the worst performer allowed through 12 percent of a set list of banned material, while the best blocked more than 94 percent.

Fewer than one percent returned false positives, and five of the six consumed less than one percent of network resources when attached but not filtering.

When actively filtering, one product chewed up to 75 percent of network resources, three used between 22 to 30 percent and one tool used less than one percent.

None of the products could identify banned material via Peer-to-Peer (P2P) file sharing networks, although one product was able to identify blocked material in "media streaming".

"Despite the general nature of advances in ISP level filtering technology between the current trial and the previous trial, most filters are not presently able to identify illegal content, and content that may be regarded as inappropriate that is carried via the majority of non-Web protocols," the report stated.

Results for the 2005 test were so bad that the search for ISP-level filters was abandoned and replaced with enterprise-level solutions. The average network resource consumption returned in the test was between 75 to 98 percent.

The ACMA test was conducted on an isolated analogous Tier 3 ISP network in Telstra's broadband e-Lab by vendor Enex TestLab. Only six from an initial 26 solutions passed the three phases of criteria; however the names of the products were kept confidential.