SIPNOC 2018 – The Robocall Summit

By Alan Percy, TelcoBridges

The SIP Network Operators Conference meeting was held in Herndon, VA this last week, bringing together roughly 100 service providers, suppliers and government regulators.  This year’s conference allocated one entire day to dig deeper into the #1 issue in telecommunications – Illegal Robocalling.

The magnitude and urgency of solving the issue was reinforced by keynote presentations from both Eric Berger, CTO of the Federal Communications Commission (FCC) and Ian Scott, Chairman and CEO at the Canadian Radio Television and Telecommunications Commission (CRTC).   Both presentation implored the service providers and their suppliers to move quickly to fully deploy the STIR/SHAKEN framework by the end of 2019.

(If you are not familiar with STIR/SHAKEN – take a listen to the tutorial found on YouTube here)

SHAKEN Implementation

Many of the service providers in attendance were in alignment on the need to implement STIR/SHAKEN and some had begun implementation.  AT&T and Verizon are leading the pack with many of the MSOs and regional carriers not far behind.  A great summary of the various service providers and their current implementation status can be found here.

With major carriers fully committed to implementation, this should cause a cascade effect on the smaller and international operators too.   As SHAKEN gets rolled out, carriers that are not delivering signed SHAKEN tokens with their calls will find call completion rates drop, putting them at a significant disadvantage in the market.   Contact centers, enterprises and consumers will find that their calls are arriving at their destination as “unsigned” or worse “SPAM likely” status.

The Green Checkmark Problem

As progress is being made toward implementation of SHAKEN, the operators are facing the next hurdle – how to report the various levels of attestation to users?   After much work in user experience testing, the ATIS came up with the Technical Report on a Framework for Display of Verified Caller ID (ATIS-1000081)  that calls out displaying colored logos on the called party’s phone to indicate whether the call is properly signed, unsigned or a known spammer.

This where the conference got exciting.

While it seems simple enough, as the numerous and sometime heated arguments made on the event list server point out:

  • In the beginning, few calls will get the coveted “Green Checkmark”.  Good callers (your bank, school, doctor’s office, workplace) will likely not be able to initiate SHAKEN signed calls immediately. Most will be unsigned, and the result will be that users will grow accustomed to not trusting the colored logos.
  • The green checkmark isn’t what callers really want. What consumers want is to have the illegal robocalls to be blocked.  (Note: As of today, service providers cannot block calls they suspect are illegal robocalls.  They can only drop traffic that would harm their network.)
  • Phone makers are starting to deliver devices with robo-blocking captcha challenges, requiring the caller to enter a random number to complete the call. Unfortunately, these can screen out legal robo-callers, making consumers miss important calls from their doctor, school, banks…
  • However, if attestation was passed to phone devices, on-device apps could us this information to improve captcha function, allowing signed calls to proceed.

While the discussion on the “The Green Checkmark” has died down on the list server, the issue is far from reaching consensus.   I’d be surprised to see a green checkmark on my phone in the next year.

“Hey Buddy, Want to Buy a Phone Number?”

There was a lot of discussion in the hallways titled “Know Thy Customer” – examining how service providers will hand out phone numbers to only legitimate users that will follow the rules and not make illegal robo-calls.  How will a service provider really know their customers plans for the numbers they issue?

I can see a side effect of this will be the creation of a black market for phone numbers, putting up strawmen buyers to acquire numbers that will be delivered with the coveted Green Checkmark.   Resold on the black market, these numbers will bring a premium with improved call completion rates (at least until the carrier figures out the scam).

The Dominoes are Starting to Fall

One thing was clear at the end of the conference, 2019 will see service providers starting to pass traffic with signed SHAKEN tokens.  The smaller and international operators will be at a disadvantage unless they get onboard and can deliver SHAKEN tokens.

To help these carriers get caught up, both TelcoBridges and TransNexus have devised a joint program to quickly add SHAKEN tokens to call traffic, avoiding expensive upgrades on existing core equipment.   The solution works for both pure SIP and legacy TDM networks, leveraging a combination of TelcoBridge’s FreeSBC and the TransNexus ClearIP service.  Sign-up to learn more at