BigPond started offering increased speeds of up to 17Mbps on its cable broadband network in March. Previously the network had delivered a maximum of 8Mbps.
Reacting to user concerns the new "Cable Extreme" plans were not delivering increased speeds to all customers, a spokesperson for BigPond acknowledged not all users would necessarily see increased speeds after upgrading but said "the vast majority will".
"We have a process in place to rebate customers where they do not get a speed improvement," the spokesperson told ZDNet Australia in an e-mailed response to questions.
"The minimum should be the same speed they got under Cable Standard, although the vast majority will see speed improvements," they added.
BigPond said limiting factors on Cable Extreme speeds included the actual plan selected, customer location, the protocol used for data transmission, current Internet traffic, the capacity and popularity of sites accessed and modem, PC hardware and software configuration.
The spokesperson said the ranks of those able to receive the full speeds were not limited to users who could receive the full 8Mbps under the original cable plans.
The Internet service provider declined to reveal how many customers had signed up for the upgraded speeds since they were made available in March.
They were similarly unwilling to comment on any evidence of users churning from other providers or other plans to the Cable Extreme plans. "Anecdotally we are hearing of 'power users' migrating to Cable Extreme," they said.
BigPond claims to have more than 250,000 customers using its cable broadband service.