TDM to IPAT&T aims to replace traditional landline voice service with a combination of LTE and U-verse in TDM-to-IP transition trials it wants to conduct in rural Carbon Hill, Ala. and in suburban Miami. The company filed its proposal with the FCC yesterday and said it expects the plan to be approved by the commission in May, with trials starting in late 2014 or early 2015 and running into part of 2017.

The filing was made in response to an FCC decision last month that invited network operators to submit proposals for TDM-to-IP transition trials. AT&T has been pushing the need for a TDM-to-IP transition to reduce the costs of operating traditional voice networks as many customers cancel those services in favor of wireless and IP-based alternatives.

In its filing, AT&T said it wants to use its U-verse infrastructure to support an IP-based voice offering in trial areas where the company already has IP broadband infrastructure. Homes outside the company’s IP broadband footprint but within the company’s LTE footprint would receive voice service based on LTE. Details about how many customers fall into each category were redacted from the version of the filing that was shared with Telecompetitor. But the company does note that Carbon Hill has a population of 6,594 spread over 172 miles, while the suburban Miami area, known as Kings Point or West Delray Beach, has a population of 64,218 spread over 32.7 miles.

About 4% of AT&T’s Carbon Hill serving area is not in the company’s broadband or LTE footprint, AT&T notes in its filing – and the ultimate fate of areas such as that is not clear.

“AT&T recognizes that it is responsible for ensuring that these customers will have an alternative available to them prior to discontinuing TDM services and is, in all events, committed to working with the commission, policymakers and other stakeholders to ensure that this happens,” the company said in its filing. “It is, however, critically important that we engage in a dialogue that addresses the geographic, demographic and economic challenges of deploying and offering broadband in sparsely populated areas.”

Potentially AT&T might be able to get support from the Connect America Fund for bringing broadband to areas such as that 4% of Carbon Hill. But details of that program are still being resolved.

Other important points worth noting in the filing:

  • Businesses in the trial areas also will be offered a choice of wireline or wireless alternatives to traditional voice service, depending on whether they are in AT&T’s IP landline or LTE footprint.
  • AT&T wholesale customers will have the option of converting traditional TDM services to IP-based alternatives. The company noted, however, that with the commission’s authorization it ultimately wants to completely withdraw TDM-based wholesale services.
  • AT&T said it “intends eventually not only to withdraw its legacy TDM services but also to retire the TDM electronics and other facilities used to provide those TDM services (and UNEs). “ The company noted, however, that wholesale customers will have the opportunity to obtain bare copper loops and use their own electronics to provide high-capacity services to their end user customers.
  • The IP-based voice services to which AT&T will be switching customers will remain subject to the existing inter-carrier compensation regimes for VOIP-PSTN or mobile voice service, as appropriate. “AT&T does not intend to test IP-to-IP interconnection in the context of these wire center trials,” the company said.
  • AT&T’s voice replacement products will support 911 services and the U-verse version will include battery backup so that it will continue to function in a power outage.

One open issue involving the TDM-to-IP transition trials is how AT&T will handle customers that currently rely on a traditional landline connection to support their alarm systems, medical alerts and credit card processing devices. An AT&T spokesman said the company is “currently developing enhancements that will provide all of these applications.” He added that the company is “committed to supporting these applications.”