Tag Archives: tandem

FCC to Ease Copper Retirement

At the end of August, the FCC issued a new Notice of Proposed Rulemaking (NPRM) that would make it even easier for telephone companies to tear down copper networks. The Rulemaking proposes to change the disclosure laws, meaning that there won’t be a lot of required notice to the public or other carriers when copper will be retired. This Docket would formalize the temporary process instituted in July where the FCC exempted telcos from many of the notice procedures for two years.

It turns out that the current FCC regulations include dozens of different kinds of notices must be given when a telco wants to tear down copper. The NPRM goes through many pages and specific language changes that are needed to eliminate the many rules associated with decommissioning copper. I have to admit that I didn’t realize how complex it is to decommission copper until I read this document.

While this is titled as an NPRM, where the FCC asks for public feedback on various proposed changes to FCC regulations, this doesn’t feel like an NPRM where the FCC is really seeking feedback. Instead, this feels like a document where the FCC has already decided what it is going to do, and this process is a formality, since not going through an NPRM and getting public feedback can lead to legal challenges. This is not that unusual, and all prior FCCs have issued some NPRMs where the results were a foregone conclusion.

This is the first FCC document in many years that hints at dismantling the vestiges of the Public Switched Telephone Network (PSTN) that is in place to interconnect telephone companies. As hard as it is to believe in 2025, a lot of that network still includes connections between telcos, called trunks, that still use the TDM technology that drove copper networks. Small telcos, CLECs, cellular carriers, and others that directly interconnect with the big telcos should be on the lookout for the disconnection of TDM trunks that carry traffic between local companies.

That will make for an interesting change in the telephone network. One of the things that protected the PSTN from the big nationwide or regional outages was that the network was arranged into regional networks that surrounded large tandem switches, most often, but not always, owned by the biggest telcos. Since 70% or more of telephone calls are somewhat local and don’t leave a region, the local PSTN trunk network allows calls to travel for free between telcos and others in a region. I would expect that, as the PSNT is dismantled, small telcos and CLECs will have to pay to carry calls to and from the replacement network.

I find it likely that as copper is retired, the tandem switching network will go with it, and the big telcos will likely establish a handful of national tandem hubs where everybody else will have to bring traffic. This has been on the wish list for the big telcos for several decades, and if they are allowed to finally dismantle the PSTN, then regional tandem switches will not be far behind.

I wrote about a similar issue in a blog last year when I warned about the dangers of 911 consolidation, which is creating large 911 hubs, meaning that a 911 call can be carried far out of state before it’s answered. That greatly increases the chance of 911 calls not working because of network issues that happen in another state. I’ve been recommending that States should consider not allowing 911 calls to be routed outside of their State.

Control of the Future Voice Network

FCC_New_LogoThe FCC is looking at how to transition from the traditional TDM-based PSTN to an all-IP telephone network. A number of carriers have submitted proposals that provide their vision of an all-IP network. Today blog looks at AT&T’s vision of the future IP network.

AT&T has proposed to the FCC that there be a handful of major switching hubs created in the country. Every carrier would then send their voice traffic to these hubs to be sorted and handed back to the various terminating carriers. Their argument is that the whole idea behind the IP transition is that the network be made as efficient as possible; they are promoting this idea as the simplest network to implement.

But is it the most efficient? Over the years I’ve done a lot of traffic engineering, meaning that I’ve helped companies analyze where their voice traffic comes from and goes to. What I’ve seen is that approximately 80% of voice traffic for most companies stays in a relatively small circle of perhaps 60 miles. This distance can vary a bit by company depending on how far away they might be from a major metropolitan area, but this basic traffic rule seems to apply pretty much everywhere I’ve looked.

So let me first look at the practical application of what AT&T is proposing. One would have to assume that if there was only a handful of nationwide interconnection points that they would be put in the same places as the major internet hubs – Atlanta, Chicago, Washington DC, New York City, Dallas, etc. What this idea means is that states not near to those hubs—say Montana, Nebraska, Maine, etc. would have to ship all the voice traffic from their state to the nearest big hub and back again.

While it might be more efficient to have only a few hubs, it certainly would not be efficient from a transport perspective. Somebody has to pay for all of that transport to and from the main hubs, and that is the real purpose behind the AT&T proposal. Under their proposal carriers other than them would pay to have all traffic brought to these main hubs. That is a major change from the way the industry works today.

Today there are two different sets of transport arrangements—one for regulated telcos and one for competitive CLECs and other kinds of carriers. Regulated companies today provide joint trunking between each other. For instance, if there is a fiber route between AT&T and another telco, AT&T generally owns the part that is within their territory and the other telco owns the part in their own territory. Sometimes this is negotiated differently, but under this arrangement both sides bear some of the cost of carrying voice traffic.

CLECs and other competitive carriers have a different situation. CLECs are allowed by the Telecommunications Act of 1996 to establish a point of interface (POI) at any technically feasible spot within a LATA (or region). Once that point is established, the CLEC is responsible for all costs on their side of the POI and AT&T (or Verizon or CenturyLink) is responsible for the costs on the other side of the POI.

AT&T’s suggested new network gets rid of both of these arrangements and instead moves all of the points of interconnection to the small handful of locations, and in doing so shifts 100% of the cost of the transport onto other carriers.

In a further money grab, AT&T would (as the assumed owner of these large hubs) charge a fee to other carriers for handing traffic from carrier to another. These fees exist today and are called transit fees. But today transit fees are charged on a relatively small percentage of voice calls since there are no fees charged for all of the jointly-owned arrangements I described above. Instead, under this new arrangement there would be a transit fee charged for every call that is handed from one carrier to another.

AT&T’s proposal is ridiculous for several reasons. First, the transit fees are not cheap and they cost more today than the traditional access charges that the FCC has been trying to eliminate. So AT&T’s proposal would increase the cost of making voice calls. The proposal is also a blatant attempt to shove all of the cost of carrying voice traffic to somebody other than AT&T. And finally, it forces companies to carry calls a much greater distance than they go today. This likely will lower call quality and increases the danger of the voice network going down due to a fiber cut or other network problem.

There is a much simpler alternative to what AT&T is suggesting, which is to let carriers negotiate how and where they hand off traffic. There are already huge numbers of local and regional interconnection points in existence, most established to hand-off local traffic in the local market. Carriers should be free to continue to use arrangements that work and with which they are happy. Think of these local arrangements as voice peering arrangements and they quickly make technical sense. Nobody is going to be unhappy if local connections transition to IP instead of TDM. But making the IP transition doesn’t mean that the whole nationwide network has to be massively reorganized. That is far more inefficient and costly than letting carriers find their own solutions.