Enex TestLab did not test ISP-level filtering products on internet connection speeds greater than 8 Mbps, raising questions of possible degradation at ADSL2+ and fibre speeds.
Further, none of the nine ISPs who piloted filtering technologies could provide an environment to test Internet Protocol version 6 (IPv6), an addressing scheme the internet industry expects will be necessary in the coming years as IPv4 addresses run out.
Communications Minister Stephen Conroy yesterday revealed the long-awaited Enex report on the Government's controversial trials of ISP-level filtering technologies.
The report concluded the filtering technologies did not degrade internet performance - except when filtering content above and beyond the ACMA blacklist, in which Enex found the filters were hampered by over-blocking.
But the report also shows that only internet speeds of up to 8 Mbps were subjected to the tests.
A shade over two million Australian households and 186,000 business and government users had connection speeds of 8 Mbps and beyond, according to Australian Bureau of Statistics figures released in June.
Internode network engineer Mark Newton - a fervent opponent of the filter proposal - said it was "extraordinary" that the Federal Government had not tested the impact of content filtering on higher speed connections.
“If the Minister thinks this report puts the speed question to bed, he's sorely mistaken," Newton said.
"[He] has to accept that this report leaves open questions about whether or not his censorship policy is compatible with his 100 Mbps national broadband network."
Update: A DBCDE spokesman has since confirmed that speeds greater than 8 Mbps were not tested as ISPs involved in the live pilot could not provide those services for testing. The same reason was given for IPv6.