August 26, 2020

Call Authentication is Necessary for the Modern Telephony Network

Modern telephony is a complex labyrinth of computer hardware, software, and network systems that's evolved over the decades. With this evolution (and growing consumer demand), more telecom companies have sprung up around the world...

Call Authentication in Modern Telephony Network

But like any industry, there are both good and bad actors in the telecom space. Robocallers and "caller ID spoofers," in particular, were once a mere nuisance. Now they are a dangerous security threat.

Caller ID spoofing is one of the most common complaints to the Federal Communications Commission (FCC). The implementation of the STIR/SHAKEN framework, mandated by the FCC, aims to combat this problem via call authentication technologies.

But how did we get to this point? How did scammers hijack the humble telephone, Alexander Graham Bell's famous invention? Caller ID spoofing happens because of the three main technologies in modern telephony.

The Evolution of Telecommunications

The telephone has evolved over the years. In modern telephony, there are three primary methods for public telecommunication:

  • Public Switched Telephone Network (PSTN)
  • Integrated Services Digital Network (ISDN)
  • IP Telephony / Voice Over IP (VoIP)

Each of these methods has its particular use, as you will see.


PSTN is the combination of the various telephone networks used by national, regional, and local telephony operators around the world. These networks provide the infrastructure and services needed for public telecommunications, including telephone lines, cellular networks, satellites, fiber optic cables, and much more. It's everything that "powers" the calls you make.

PSTN used to be a network of analog systems, but it's now almost entirely digital. With the switch from analog to digital infrastructure, scammers saw vulnerabilities in the system, and exposed them.

Today, PSTN works by facilitating a network of "switches" that route calls, from one destination to the next. (Your home to mom's home, for example.) Once you click the "call" button on your landline or traditional cellular service, your call passes through several destinations — fiber optic cables, then cellular towers, then satellites, etc. Networks transfer communications from one location to the next, almost seamlessly. It's happening all the time. It's happening right now.

Did you know... The government of the U.K. will "switch off" PSTN in 2025 and replace it with a digital "all-IP" network?


ISDN is similar to PSTN, but with one main difference: It transfers data, as well as speech, through multiple location points. This technology came about in the late '80s. Before this, the telephone system primarily transferred voices — or "speech." This technology transfers data (in "packets") from one location to the next via the PSTN system.

ISDN involves several types of access interfaces, including:

  • Basic Rate Interface (BRI)
  • Broadband ISDN (B-ISDN)
  • Narrowband ISDN (N-ISDN)
  • Primary Rate Interface (PRI)

One of the benefits of ISDN (compared to PSTN) is its ability to transfer data quickly and make calls clearer, so it's the preferred communications method for many telecom companies.

Did you know... ISDN runs on a regular copper wire, which reduces the cost of this technology?


VoIP utilizes broadband networks to transport voice communications from the caller to the recipient. This is how it works: VoIP converts audio into packets of data via something called "codecs" and transmits these data packets over an IP network. VoIP doesn't rely on the circuit-switch network that phones traditionally use, so it's cheaper for many telecom companies (who pass on these savings to users). As a result, VoIP is the no.1 communication method for many internet users.

Did you know? Most people consider VoIP a relatively new technology, but the first VoIP call was made in 1974!

How Do Scammers Use These Technologies?

Many years ago, the telephony network had tighter regulation and, consequently, fewer problems with scammers. Because large, trusted telecom companies dominated these networks, call spoofing wasn't an issue. With the advent of VoIP services, in particular, more telecom companies entered the marketplace and many didn't have the infrastructure to protect consumers from robocallers — or turned a blind eye to the problem.

Then the problem got worse. And even worse.

In 2018 alone, Americans received 26.3 billion robocalls. That's more than three times the world's population.

What is the Government Doing?

To combat caller ID spoofing, telecom companies have to implement call authentication technologies — or face expensive fines from the government. STIR/SHAKEN provides the technological framework for carriers to authenticate calls at source and warn customers about potentially fraudulent callers before they pick up the phone.

Telecom companies can also use data metrics to pinpoint locations and bad actors likely to spoof calls and steal personal and financial information from consumers.

Still, STIR/SHAKEN won't be the end of the caller ID spoofing problem. The FCC mandates that carriers authenticate calls by June 2021, but the coronavirus pandemic might push back this date. Plus, the technology itself is far from perfect. Call authentication technologies could flag legitimate calls as a "scam" or "spam" and prevent genuine companies from reaching customers. Genuine companies like yours.

How This Impacts Your Business

At the moment, consumers feel scared enough to answer calls from companies. With so many horror stories about robocallers stealing money, you can't blame them. However, as a legitimate company, you have every legal right to contact your customers. You (and your sales agents) rely on the modern telephony network to:

  • Engage prospects
  • Make sales leads
  • Facilitate customer service communications
  • Sell products and services

Won't STIR/SHAKEN make this much harder?

It's a catch-22.

  • Scammers can spoof your number and tarnish your business reputation
  • Government initiatives like STIR/SHAKEN can flag your number and tarnish your business reputation

What should you do?

Final Word

Let's make this clear: Call authentication is necessary for the modern telephony network, which is riddled with scammers and call spoofers. We believe call authentication is a good thing. But STIR/SHAKEN can make it hard for businesses to survive, especially in the current climate.

This is where a service like Caller ID Reputation comes in. It lets you check if telecom companies have blocked your caller IDs (or marked them as "spam") in real-time, so you can save your business.

See how Caller ID Reputation® can support your business!

Caller ID Reputation Benefits