Whether at an ISP or PC level, internet filtering may not need to be legislated, according to the Australian Greens.
The minor party today released details of its cyber-safety policy, which focused heavily on research, education and law enforcement.
It proposed to redeploy funds allocated to the Labor Government's internet filtering plan, believed to be up to $40.8 million.
Instead of mandatory filtering, the Greens proposed that ISPs be forced to "offer filtering to all new customers", who would be unable to use the internet until they opted in or out of filtering.
Greens communications spokesperson Scott Ludlam said ISPs could choose whether to offer PC-based software filters, modem or router filtering, or ISP-level filtering.
PC-based filters were expected to provide more comprehensive filtering of adult content, and have fewer technical problems than ISP-level filters since they dealt with less traffic.
But Ludlam said the Greens were "agnostic" about where filtering should take place, highlighting ISPs like South Australia-based Webshield that already offered opt-in, ISP-level filtering.
In terms of internet filtering, the Greens' proposed legislative environment would not be much different than it is today.
"I'm not sure that it [internet filtering] would necessarily require legislating, to be honest," Ludlam told iTnews.
"It is filtering where people feel it's most appropriate. We're agnostic about where it should be - there are some ISPs that are offering it and we're fine with that, but it should be opt-in."
The Greens did not provide financial details for the provision and distribution of filtering solutions under its policy, noting that stakeholders had indicated that it could be implemented "at no cost to the taxpayer and very little cost to ISPs".
"I've spoken to a number of folk in the industry who don't believe that there will be a financial cost associated with that [providing free PC-based filtering]," Ludlam said.
"I'm not entirely sure that it will be a great cost, but we do have provisions - particularly for smaller ISPs - if it does prove to be a financial burden."
The party called for "an immediate halt" to spending on the Government's ISP-level filtering proposal.
Instead, the funds would be spent on research into the risks faced by Australians online, and used for online media literacy programs at schools, universities and public libraries.
The Greens also proposed more funding be provided to cyber-crime units in the States and Territories and the establishment of a national, online portal for reporting cyber-crime.
Discussing similarities between the Greens' filtering policy and that of the Coalition, announced last week, Ludlam said most parties were converging on a view formed from industry advice.
"Apart from the Government obviously, other parties are converging on what the industry and stakeholders have been saying for years," he said.
"I don't think we can be accused of pinching from the Coalition's policy; I think we're just drawing from the same pool of stakeholders and experts."