The first panel discussion of our virtual conference (back in September) explored how the PSTN has evolved over the past 10-20 years and where it’s headed.
You’ll notice that in step 3 of my mini history lesson we hit a roadblock in the evolution from TDM to VoIP. Independent telcos are stuck in limbo – with networks that are half VoIP and half TDM. This is a ridiculous situation from a technology point-of-view and it’s driving me crazy that no-one seems to be doing anything to fix it.
If you haven’t heard me rant about this before, let me give you a little background. While the FCC requires large network operators (think AT&T / CenturyLink) to provide interconnect to their local tandems to ILECs and CLECs, they don’t specify what technology should be used.
These trunks have traditionally been provided using SS7/ISUP, and even today the vast majority of connections to local tandems are only offered over SS7 – there’s no SIP trunk option.
This has two major consequences for ILECs and CLECs:
- If they want to own their number block and LRN, they have no option but to maintain TDM media gateways, which are (a) expensive and (b) headed inexorably towards end-of-life.
- Any calls signaled over these TDM trunks don’t support the standard version of STIR/SHAKEN, which means there’s no way to validate caller IDs. For inbound calls this means your subscribers are going to receive more robocalls than they should. For outbound calls this means there’s a greater chance that your subscribers’ calls will be blocked as potential robocalls.
From what I’ve read/watched of FCC discussions on robocalls, it sounds like they’re characterizing rural carriers as laggards who want to stick with TDM – when the truth is that rural carriers are prevented from moving to a fully VoIP solution by the tandem providers. And no-one is doing anything to fix it.
Hence we end up in this limbo state. Independent telcos are frozen in time with a half-VoIP, half-TDM network – and as a consequence are disadvantaged against the larger network operators.
We regularly work with clients who want to understand how to build a network that will support their customers for the next 20 years, and it’s frustrating to be hamstrung by these issues.
I have written about this before and since then I’ve been talking to people in the industry every chance I get, and I haven’t heard anyone disagree about the core problem. For some reason the FCC and even NTCA don’t seem overly inclined to push this issue, and so we’re stuck. Stuck waiting for AT&T to make it easier for small carriers to connect to them. Good luck with that.
I’d better go take my medication now and look at some photos of baby pandas.
(courtesy of Flickr user fortherock)
Ah…. that’s better.