The Australian Competition and Consumer Commission (ACC) has said that NBN should regularly report and keep logs of information it hands over to Telstra.
In March, the ACCC called for feedback from industry over a proposed carrier licence condition to be placed on NBN to force the company to make all information available to retailers at the same time as that information is made available to Telstra.
Due to the shift to the multi-technology mix that will use Telstra's legacy copper and cable networks, the wholesale arm of Telstra will be working much closer with NBN during the rollout and will, as a result, have access to information that it wouldn't have had prior to the change in policy.
The ACCC has recommended in a report released on Tuesday following the consultation period that NBN send reports to stakeholders on a regular basis, maintain a list of all documents provided to Telstra, and make those documents available to Telstra's rivals on request.
The watchdog has also said that Telstra should not know which NBN provider a customer chooses to go with unless there is an issue with migration.
Key information that NBN should provide would include the current information provided, such as the three-year rollout plan and proposed footprints, but would also potentially include new information such as what stage in the construction process an area is in, rack space at points of interconnect, and line quality information.
The ACCC noted that Telstra would have access to historical information on the quality of the copper line for premises getting fibre to the node, and said this information would also be helpful for retailers in determining what services to provide.
NBN said it plans to address this by making an "online service qualification tool" available to retailers to check the line quality at premises.
ACCC chairman Rod Sims said that the proposed disclosures to be included in the carrier licence for NBN would help retailers make business planning and investment decisions.
"These measures will also support competition by placing interested stakeholders in an equivalent position to Telstra in the transition to the NBN," he said in a statement.
"Consumers will in turn benefit from stronger competition amongst NBN service providers for their business."
The report prepared by the ACCC will be considered by Communications Minister Malcolm Turnbull before making a decision on whether to impose a carrier licence condition on NBN.