Dan Warne11 February 2009, 5:45 PM
Australia's second and third largest ISPs, Optus and iiNet, won't be included in the government's internet filter test upon its launch.
“The Government is committed to take an evidence-based approach to implementing its cyber-safety policy and these trials will provide valuable information to inform our approach,” Senator Conroy said.
“The government is well-aware of technical concerns about ISP filtering and that is why we are conducting a pilot, to put these claims to the test.”

However, it seems Conroy isn't interested in testing the filtering system in the highest traffic ISPs, at least when the filtering pilot launches.
Optus had said it would only participate in a limited scale trial of the system -- blocking a blacklist of URLs supplied by the government, but not the more comprehensive opt-in porn filter that the government also wanted ISPs to test.
iiNet said it would only participate in the trial to prove that centralised internet filtering wouldn't work.
Senator Conroy's office confirmed that the six ISPs would be Primus, Tech 2U, Webshield, OMNIconnect, Netforce and Highway 1. Only Primus has more than a metaphorical handful of customers compared to the largest ISPs in the industry, and WebShield is an ISP that already filters its customers' connections as a selling point.

Above: the website of Tech2U, one of the ISPs the Australian Government has chosen to base its internet filter testing results on.
Conroy said testing with each ISP would take place for a minimum six weeks once filtering equipment has been obtained and installed. It will look at the efficiency and effectiveness of a range of technical solutions, as well as other issues such as the ease of circumvention, impact on internet speeds and user experience.
The Senator appeared defensive about the controversial filtering scheme, which has drawn overwhelming criticism from the Australian electorate. “ISP filtering is no silver bullet and the Government is implementing a comprehensive set of measures to combat online threats,” he said.
When asked if iiNet was excluded from the trial because it stated that it simply wanted to show that the scheme wouldn't work, a spokesman for Senator Conroy said, "Is that a serious question? The first phase of the Government’s Internet Service Provider (ISP) Filtering Live Pilot will begin with an initial six ISPs. Arrangements for the first phase of the live pilot have been finalised with six ISPs while consultations continue with a number of other ISPs that have applied to take part.”
When asked by APC whether the government saw any problem with running a scientific trial in which the test ISPs were chopped and changed throughout the test period, the spokesman responded:
"As we've explained previously, in December ISPs made applications to take part in the live pilot, detailing the extent of their involvement, the technical approach they would take and other matters. These applications have necessarily required evaluation and consultation before participation is finalised. This has taken longer with some than others."