MOVES to force telecommunications companies to retain all Australian's metadata could create a "pot of gold" for future hackers, a Telstra advisor said Thursday.
The government's controversial reforms were examined during a day of parliamentary hearings in Canberra on Thursday.
While intelligence and police authorities have continued to support the plans, concerns were reiterated by several groups about the definition of metadata, the planned two-year period for retaining the data and potential cost to the industry.
Telstra's Michael Burgess told the committee that while the company already held much data, the new regime would require a whole new system of collecting, retaining and indexing much more data.
He said currently Telstra had 13 systems where similar information and billing data was kept, but that a centralised system would need to be created.
"We'll need to create that system, and hackers will take advantage of that - they'll go for the least effort to extract that data and because of that, we would have to put extra (protection) measures in place," he said.
"If I was a hacker, you would go for that system, go for the pot of gold, as opposed to having to go through the multitude of systems that are in place today."
While concerns about the security of such an industry-created system remained, other witnesses warned of potential privacy implications.
Privacy Commissioner Timothy Pilgrim urged the committee to reconsider putting the specific definition of metadata in the legislation, rather than the government's proposal to enact the definition in regulation.
But, if it was to be enacted through regulations, Mr Pilgrim told the committee any future changes should be vetted by a "privacy impact assessment" or future privacy commissioners be consulted on such changes.
The hearings continue on Friday.
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