This week's fault that knocked out Internet access for thousands of Telstra BigPond customers was most likely related to the ISPs domain name system (DNS), according to people affected by the outage.

Internet access was not available to BigPond customers for about one hour between 7 and 8am yesterday.

One BigPond subscriber, who requested anonymity, told Computerworld Internet access was suddenly disrupted when local and international Web portals like Google and Yahoo! could not be reached.

“Everything was working fine, including my modem, PPP connection and ADSL link when I could not access international Web sites,” he said.

“Some local sites were still accessible, but I was already logged on so my browser wasn't doing a DNS lookup.”

Members of the local network operator's group, AusNOG, reported a loss in Next G mobile data services in Brisbane and Melbourne, also at the time of the ADSL outage.

Others complained of no fixed-line access, even to data centres.

Broadband forum Whirlpool has received scores of complaints from Telstra BigPond subscribers who could not access local or international Web sites.

Telstra has since confirmed the outage was related to DNS services "because of an issue with our international gateway”.

The gateway could not find the domain names of Web sites, so people could not access the Internet if it was an international site or one with international content, according to the company.

The outage follows a recent number of high-profile service interruptions at Sydney data centres.