Ta ta, TDM: Verizon pushes voice switching into the cloud

Landlines aren’t sexy anymore. But that doesn’t mean they’re gone. Though a dying service, fixed voice connections are still used by tens of millions of U.S. retail, business and government customers. And so, operators like Verizon are looking to the cloud to modernize their services and, hopefully, save a few bucks in the process.

Ribbon Communications is one of the companies working behind the scenes with operators to help them move their switching operations to private cloud infrastructure. CEO Bruce McClelland told Fierce that it’s been working with Verizon on this kind of initiative for a while now, but added the pair are now looking to drastically pick up the pace.

“We actually do a fair amount of this already today at a certain pace,” McClelland said. Though he declined to disclose exact figures, he said the new upgrade program it is tackling will see Verizon complete about five times as many legacy TDM switch migrations as it had been before.

So, what exactly does the upgrade process look like? McClelland set the scene.

Old switching infrastructure lives in a facility like a data center, with rooms and rooms of decades old, power-hungry equipment (think stuff that dates back to the Nortel and Alcatel days) stacked in rows. This can all be replaced with just a couple racks of modern servers running GPUs and digital signal processing technology.

But first, an engineering assessment must be done. And then comes the hard part: the cabling. All of this needs to be rerouted and done so while the voice lines remain in service. Once that’s done the new servers are hooked into Verizon’s private cloud infrastructure and voilà!

It’s easier said than done, of course, but McClelland said it has developed a speedy model with Verizon that he believes can be replicated for other operators and enterprises looking to upgrade their voice services.

"It can take three months or it can take nine months for an individual switching location to go through that migration," McClelland said. "So the way you accelerate that is you really develop a methodology that can be replicated in each site. You have a dedicated tiger team that's going out and doing nothing everyday except working on these types of programs and you increase the scale that way and that helps us reduce the cost."

Wait. Speaking of cost, what was that bit about saving a few bucks we mentioned at the beginning?

Well, McClelland said the ability to replace rooms and rooms full of gear with just a few modern racks means operators can reap real estate, cooling and power savings.

Verizon could not immediately be reached for comment.

However, the operator noted on its TDM migration page that "TDM over copper and fiber based services are very expensive to maintain, have very limited replacement parts for repair and they do not provide the flexibility, reliability or suitability for next-generation services." It also highlighted power and space savings associated with modernized networks. 

Ta ta, TDM

For what it's worth, Verizon isn't the only operator working with Ribbon on such a transition. McClelland said during the company's Q3 and Q4 2023 calls that it is also working with AT&T on TDM upgrades. That partnership could eventually yield "tens of millions of dollars" in revenue for Ribbon as work ramps in 2024 and 2025.

AT&T's efforts to update its network are no secret. The operator in 2022 notably set a goal to cut its copper footprint in half by 2025.

McClelland told Fierce what while AT&T and Verizon likely have the most significant share of remaining TDM lines, upgrades are something all legacy operators – including the Lumens and Brightspeeds of the world – are looking at,

"We're having detailed discussions with several of our largest customers regarding their plans over the next several years to address their remaining TDM and copper networks, and we expect a big push in this area," he stated on Ribbon's Q4 call in February. "We also expect practically all U.S. federal agencies to initiate voice modernization projects in 2024."