Much has been written about robocalling (“the scourge of civilization” as FCC Chairman Pai calls it), and much has been written about the STIR/SHAKEN frameworks and how they are going to solve the problem.
But I’m not sure it’s that simple.

What if STIR/SHAKEN solves the problem only for the big incumbent carriers, and makes things worse for independent service providers, CLECs and their customers?
Does that sound unlikely? I disagree – in fact it’s the most natural outcome.
(If you want some background on this topic, check out “Caller ID Spoofing explained: using ancient wax seals“.)
Consider these two facts:
- STIR/SHAKEN allows a caller ID to be validated ONLY if the entire end-to-end voice call travels over SIP.
- Most (if not all) RBOCs only allow ILECs and CLECs to connect to their tandems over SS7/ISUP.
Think about that for a moment.
If all the major carriers implemented STIR/SHAKEN today (with SIP connections throughout their network), it seems like we’d be in a pretty bad situation.
- Any call from one of AT&T’s subscribers would have a validated caller ID, and if this was routed entirely over SIP (e.g. within AT&T’s network or to a CenturyLink line) the recipient could validate the token and the recipient would see a smiley face next to the calling number (or whatever mechanism is used to indicate that the caller ID is valid).
- Since the majority of numbers are owned by the RBOCs, most people would become used to this happy face.
- Any call that originated from an independent / competitive service provider’s network AND was routed to the RBOC via their SS7 interconnect could not be validated. No smiley face. Or worse, maybe a sad face. Therefore the recipients would be much less likely to trust / answer calls from your subscribers. If you have business customers, this is very bad news.
- On the inbound side, if you’re receiving calls from AT&T over these SS7 trunks (which is most calls – because your numbers are probably homed off their tandem), they can’t be validated. So your subscribers start saying “how come I don’t get robocalls on my cell phone, but I get them all the time on the line you provide?” Again, this seems like bad news.
In this scenario, independent / CLEC subscribers become second class citizens of the phone network. They are unable to authenticate caller ID and this causes huge frustration on both inbound and outbound calls. And so they cancel their service.
This seems like a huge problem.
I mean, obviously the RBOCs could suddenly start offering SIP trunks to everyone, and roll that service out across their entire network in the next year or two. But really… does that seem likely?
Am I missing something? Or is this really bad?
Seriously. I want to hear your thoughts. Did I misunderstand something, or is this a catastrophe waiting to happen?
P.S. I understand that many people send outbound LD traffic over SIP trunks, which certainly helps. Outbound local traffic is still a problem though (especially for CLECs).
P.P.S. For inbound calls, I’ve written before about the idea of an access homing tandem where you could redirect inbound traffic to Inteliquent or Peerless Networks, but even if you went to the trouble of doing that you still have the same problem for any local traffic between you and your local RBOC. So with a lot of effort you could make the situation less bad – but it’s still bad.