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Stop spam calls directly in the network

Everyone has tried it. Those annoying callers who are ringing and bothering you a lot at the worst possible time. Most of them are innocent sales calls, but others are actual scam calls that try to lure money from us, making many of us victims of scam calls. As a result, very few of us now dare to answer a call when we see an “unknown number” on our screen. Maybe it’s an important call that I have to answer anyway?

Unfortunately, spam calls and scams have increased during the global COVID-19 pandemic 2020-21, with a sharp rise in scammers trying to lure people into buying drugs, vaccines, and non-existent lead times for vaccinations. Scam callers often look very professional when they contact their victims, so it is easy to deceive people, especially when we are in a vulnerable position regarding our own health and finances, not to mention our families.

old man with phone

Scam calls and spam increase through pandemic

Based on the 2020-21 data collected by Hiya, a tech company that specializes in protecting people from spam and fraudulent calls, we can see some interesting stats and stats. In general, spam calls and fraud dropped significantly at the start of the pandemic. This drop was most likely due to disruption caused by shutdowns – call centers were closed, spammers had to work remotely, and many likely did not have the resources to resume a large number of outgoing calls. Hiya’s data showed a 35 percent drop in spam and fraud calls from March to April 2020, representing the lowest monthly total for spam calls during the pandemic.

Spam calls and fraud dropped dramatically at the start of the COVID-19 pandemic (Source:

Figure 1: Spam and fraud calls dropped dramatically at the start of the COVID-19 pandemic (Source:

After the initial decline in April 2020, spam calls and fraud gradually increased and by July 2020 had quickly rebounded to pre-pandemic levels. With the economy reopening and a large number of overseas callers resuming their operations, spam and fraud calls have skyrocketed. Between November 2020 and April 2021, spam calls increased by 67 percent worldwide and scam calls increased by 35 percent. Compared to the lowest baseline in the epidemic in April 2020, there was a significant 364 percent increase in spam calls and a 327 percent increase in fraudulent calls over the following 12-month period.

One of the biggest scams that emerged during this period was COVID-19 related scams, including scammers selling fake vaccines and fake health insurance. Hiya has also prevented fraudsters from stealing government assistance related to COVID-19, such as the US Stimulus Verification scam where fraudsters attempted to steal money from Americans by impersonating government agencies or promising to deposit money the same day. COVID-19-related scams originally rose at the start of the pandemic with an 811 percent increase from February to March 2020. Although COVID-19-related scams declined from June to October 2020, March 2021 saw the highest number of cases Corona virus. Related scams at all times, an increase of nearly 7 percent over the previous year.

The most common scam related to COVID-19 in 2021 was the vaccine scam where fraudsters tried to sell fake vaccines, fake vaccination cards, and the promise of a non-existent vaccine date. COVID-19 vaccine-related scams experienced significant growth in 2021, increasing by 208 percent in the first quarter of 2021.

Spam calls have spiked during the COVID-19 pandemic.  From April 2020 to April 2021, there was a 364 percent increase in spam calls and a 327 percent increase in scam calls.  (Source:

Figure 2. Spam calls soared during the COVID-19 pandemic. From April 2020 to April 2021, there was a 364 percent increase in spam calls and a 327 percent increase in scam calls. (Source:

While the US saw the highest number of spam and fraud calls, European countries also quickly became prime targets – likely due to a lack of regulation and call protection services, making Europe a more vulnerable market than the US. In the UK, for example, there were a total of 6.6 billion fraud calls reported during 2021. This resulted in an average of 12 fraud calls per head of the population per month. The economic impact of such a massive hike has hit people hard – an average loss of $680.17 per subscriber.

Problems with existing phishing and spam blocking solutions

So, how can phone users avoid receiving unwanted calls?

There are various solutions developed in the market to block spam and scam calls. Some solutions analyze spam calls and fraud when people call service providers to complain about certain phone numbers, and then the service provider blocks those specific phone numbers. Other solutions include a list of known spammers to block calls. The list is often produced by regulatory authorities and has the disadvantage that the contents of the list are not updated as frequently as needed.

One of the latest and most popular solutions is that a smartphone user downloads an app on their phone which allows them to block numbers that they themselves consider to be spam. However, the application-based solution has many problems, such as:

  • Spammers can invalidate the filter by changing the original number
  • The app needs to be updated regularly and can be very slow to respond to spammer development methods
  • Checking the database can add latency to incoming calls
  • There is no uniform level of service across the entire network

The combination of these factors makes getting rid of spam and fraudulent calls cumbersome for individual users.

Calling service providers can now block unwanted and scam calls directly in the network

Of course, perhaps the easiest and most effective way is to block a spam call that is already in the service provider’s network, so individual users don’t have to see or worry about call blocking alternatives. This network-based solution will identify suspicious behavior based on a lot of spam calls and spammer tactics, and prevent callers identified as spam and scams from accessing a subscriber’s phone directly in the network.

Block spam calls directly in the network so that these calls do not reach users' phones

Figure 3. Blocking spam calls directly in the network so that these calls do not reach users’ phones

But here comes the crucial question: How can a network know which calls to block and which to allow? This is where intelligence comes in with phone call analysis systems.

Ericsson and Hiya have teamed up to develop a solution that blocks spam and fraudulent calls directly into the Network IP Multimedia Subsystem (IMS), the part of the network that enables 4G and 5G mobile voice calls. It is built on new software in the Ericsson Multimedia Telephony Application Server (MTAS). For voice calls made over 2G and 3G networks, spam calls can be blocked via Ericsson Mobile Switching.

High-level overview of Ericsson's call qualification solution

Figure 4. Ericsson high-level overview of the call qualification solution

Hiya’s cloud-based analysis system performs real-time serialization of existing and new data, meaning it can determine whether a call is wanted or unwanted within milliseconds. To do this, it uses public and proprietary data sources, including insights from the Hiya Network, and builds on constantly learning trust models that examine every call.

So, does this make it possible to block all spam calls? Well, yes and no. You can, of course, block all calls that come from unknown phone numbers, but sometimes users still need to be reached by people they have not spoken to before, for example a local plumber or a specialist doctor. So, there is a balance to block as many annoying calls as possible, but also allow calls that users want to answer. As scammers and criminals are always trying to devise new ways to deceive people and circumvent new spam blocking techniques, the intelligence in the system must be able to adapt quickly.

It’s of course a huge relief to most people if 50 percent of all spam calls are actually blocked, and 75 percent isn’t unrealistic. But it’s also important to remember that setting the network or your personal phone profile to block 100 percent of unknown calls is probably not a good idea because you may be blocking the calls you want to receive.

With problems, new business opportunities arise

Often times when we encounter a new problem, we spend most of our time trying to solve it right away. Herein lies the opportunities for new technologies and even new businesses. If we start to work a little more on the technology of blocking “unknown numbers”, we realize that there are also opportunities to develop what is displayed on the screen of incoming calls. For example, instead of displaying a generic text string, we can develop a solution that provides detailed information about the actual “unknown” caller.

For service providers, this likely means that they can provide a service with “confirmed numbers” and sell it to various businesses, corporations, and government organizations. By seeing the name of the company or government on the incoming call screen, along with an approved “stamp” that the phone number belongs to the company you’re calling, can make the user or company feel more confident and more likely to call the caller.

An example of how a verified call would appear on the incoming calls screen.  Another possible option could be to display company logos.

Figure 5: Example of how a verified call would appear on the incoming call screen. Another possible option could be to display company logos.

Such a service can save a lot of wasted time and money for serious business and government agencies trying to communicate with their current and potential customers or citizens via phone calls that are suspected of being spam and therefore go unanswered. Remember that most consumers want to be contacted via phone calls on important matters.

Examples of business costs for spam calls to various companies and government agencies

Figure 6: Examples of commercial costs of spam calls for various companies and government agencies

Blocking unwanted calls offers many benefits to consumers, such as bringing more peace of mind, less frustration, and less downtime. Businesses and governments will benefit from increased likelihood of customers picking up the phone, lower operating costs and increased trust and brand value.

It’s time to stop the multi-billion dollar spam and fraud industry for good. I think the most effective way to do this is to stop spam calls directly in the network using a new smart technology.

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Press release: Ericsson and Hiya aim to make spam and scam calls a thing of the past