Telecom plans to reveal details within days of an inquiry into the collapse of the XT mobile network last week and compensation for customers.
About 100,000 customers south of Taupo were cut off from Wednesday to Friday by the fault. It was the second major breakdown in just over a month.
The network was launched in May last year.
The Telecommunications Users Association says compensation is useful as a public relations exercise, but only proven reliability will restore public confidence in Telecom.
Chief executive Ernie Newman says the public has a right to know why the problem happened, how it was handled and what is being done to stop it happening again.