Mobile phone operator Vodafone Australia confirmed it has secured additional network capacity from Optus, which should prevent a repeat of the congestion experienced across the Christmas and new year period that stranded thousands of international text messages.
Vodafone conceded it had insufficiently forecast the volume of text messages sent over the holiday period, leaving the network beset with delays that were resolved only late on Friday.
"We recognise it was an ongoing issue for [between] seven and eight days," a Vodafone spokesman said.
Vodafone said 32 million text messages were sent on its network in the 24-hour period around New Year's Eve and New Year's Day, a sharp increase on the 25 million sent in the same period last year.
It blamed the problem of failed messages on congestion on its international signalling links, a service provided by Optus.
Earlier last week Vodafone said it had asked for extra capacity from Optus but had not received an adequate response; but later it appeared to backtrack on that claim, pinning the problem down to its own lack of foresight on the volume of messaging traffic.
Optus confirmed it had not experienced any congestion with text messages on its network during Christmas and new year.
Vodafone customers texting friends and family overseas became aware of the problem when mobile text messages failed to send or appeared as "pending" for days. Text messages sent to the United Kingdom, New Zealand and the United States were particularly affected, according to reports from customers. The messages, once sent, would still be billed to customers even though they would be out of date when received by recipients.
Vodafone said it became aware of the problem on Christmas Day and had been working since then to correct the issue.
"With international roaming services now returning to normal, Vodafone Australia and Vodafone New Zealand are undertaking a full review of the international signalling capacity required for roaming customers, particularly during peak periods" such as Easter, the opening of the Beijing Olympics in August and World Youth Day in Sydney in July, the spokesman said.
— Australian Financial Review