AUSTRALIA (ZDNet Australia)--The severed cable left an estimated one million customers between Palm Beach and Queensland without telephone, Internet and data services for well over a day.
Telstra said it had "envisaged something like this would happen" and the additional cable was already in the planning stage before last Thursday's mishap.
A NSW government agency, the Rail Infrastructure Corporation, which maintains railway tracks, has emerged as a possible culprit for the damage, confirming it was working in the area at the time.
According to Telstra, the eastern seaboard cable runs at diverse paths in the main. This means that two cables run in conjunction with one another so that traffic on one cable can be re-routed to the other if a cable is damaged or to meet increased capacity demands.
However, the eastern seaboard infrastructure comes together at some points for "connectivity and accessibility reasons" and unfortunately that's the point where the cable was severed, a Telstra spokesperson told ZDNet.
"It may be seen as a weakness to some degree where the cut occurred," he said.
However, "once a second cable is laid, traffic will automatically be re-routed [to it] if there is any damage to the existing cable," he added.
Telstra said the new cable is "waiting to be commissioned" and wouldn't specify when it would be fully operational, saying only that it would be in the next few months.
Telstra has 3.1 million kilometres of network Australiawide and is mostly able to re-route traffic but "there are a select few cases where it may not happen," the telco said.
It would not confirm what proportion of its network is unable to re-route traffic or whether it is planning further additional cabling in areas of such weakness.
"Telstra is always planning additions to the network and does that so customers, in the case of unforeseen circumstances, are not negatively impacted."