CALL MASKING IN TELECOM NETWORKS

Besides the security risks, number masking leads to significant revenue loss for telecom operators, argues SONNY ARAGBA-AKPORE

  It is unusual to receive supposedly foreign calls only for the caller identification to show a local number. Strangely, many people take this for granted especially if eventually the caller is able to identify him or herself on the other side. Talks go on as if nothing has happened. Really? The caller on the other side may be or may not be aware that his or her number didn’t show on this side of the communications link. What has happened is “Call Masking”. It is dangerous to the receiving end and very big economic loss to local network operators.

It is call dumping that is a potential national security risk as threats and intimidation take place and detrimental to the receiving end and society. And no traces of the caller as the number does not show actual caller who may well pass as a ghost. Call masking is the act of concealing or disguising the origin of an international call and presenting it as a local call. The International Telecommunication Union (ITU) addresses call masking primarily through recommendations that combat fraudulent practices like spoofing and refiling, which manipulate Caller Line Identification (CLI).  Although ITU does not ban all forms of call masking, its guidelines aim to ensure the delivery of true call origin information, combat revenue fraud, and protect users from illegal activity. These include evading international call rates where one of the most significant problems identified by the ITU is the masking of international calls to make them appear as less-expensive local calls. This call refiling or masking helps operators and fraudsters bypass international termination rates, causing massive revenue losses for legitimate network operators.

Call masking is executed  through a deployment of a technology called SIM boxes, which are devices containing multiple SIM cards deployed to terminate international calls as local ones.  The practice bypasses the higher international termination rates, allowing illegal operators to profit from the difference between local and international call costs. 

 Call masking in Nigeria and indeed anywhere in the globe is the illegal practice of disguising incoming international calls as local calls to exploit the rate difference between international and local call charges, leading to significant revenue loss for telecom operators and potential security risks. The Nigerian Communications Commission (NCC) put measures in the past to combat this through technical solutions, public awareness campaigns, and stricter enforcement, which led to arrests and a decline in the practice until recently when the practice resurfaced.

 On Wednesday, December 8, 2021 the Federal Executive Council (FEC) at its weekly meeting approved N1.8 billion to combat the menace of call masking in the country.“The first memo that was approved by the Federal Executive Council was for the deployment of regulatory systems in the telecommunications industry, to be implemented by the Nigerian Communications Commission (NCC),” then Communications and Digital Economy Minister, Isa Pantami announced. He said then that money will be deployed for regulatory systems  that will have two components to help tackle insecurity in the country and bolster revenue generation by the government. 

The minister said the systems were expected to fight criminal activities perpetrated through SIM box traffic and call masking traffic.  But it is however not clear how much success was recorded because as we write now, the scourge has resurfaced in delicate dimensions. And despite spirited efforts to combat this, the problem has resurfaced through Subscriber Identification Module (SIM) box activities in general.

SIM boxing is a fraud allegedly committed via the use of a SIM box, by diverting international calls to a cellular device through the internet. The device, routes the connections back into the network as local calls, using hundreds of low-cost or even unpaid and unregistered SIM cards, which are often obtained with forged identities. “The scammers thus benefit by exploiting the difference between local and international charges by paying just local rates or none at all to network operators after billing international rates from the source. The caller pays the high call rates, but the local telecom operator does not collect these, leading to revenue losses to the Mobile Network Operators (MNOS) and the government” an industry player said. With sustained losses by industry players put at nearly $3billion so far, call masking didn’t come open until about eight years ago when operators lamented losing about 2.5 million minutes per day to the activities of the alleged fraudsters.

Although the NCC put in remedial measures to check the menace, the scammers appear to be ahead of the regulator. But an insider said “the commission is aware of the prevalence of the criminal activities and was deploying more technical solutions to tackle the situation “.

Arrests made in the past revealed that the alleged perpetrators of SIM boxing had multiple SIM cards registered with fictitious names and used to divert international calls.

Call masking, also known as number masking, is a technique used in telecommunications to conceal the real phone number of one or both parties in a call, typically by substituting it with a temporary or proxy number. While it is commonly used to protect user privacy in ride-hailing apps, customer service platforms, or delivery services, it is viewed as calls with sinister intentions. It leads to call quality degradation because extra layers of routing or anonymization may affect latency or audio quality. “Proxy numbers can introduce complications in call routing, especially if there’s network congestion or number recycling,” a telecom engineer admits.

Repeated misuse by bad actors erodes trust in legitimate services using call masking for privacy.

There is also a false sense of security as users might believe their data is secure, but masking does not guarantee end-to-end encryption or data protection.

In many regions of the world including Nigeria, masking without user consent or proper authorization are clear violations of telecom laws. There are sanctions in various degrees.

In this regard, organizations may face heavy fines or license revocations if call masking is used inappropriately or without safeguards. Such safeguards include but not limited to verified and regulated masking solutions and implementation of strong logging and monitoring systems.

  Operators are admonished to educate users about masked calls and potential fraud.

Cooperating with telecom regulators and law enforcement, when necessary, could be one of the safeguards. But regulators are sometimes incapacitated especially when real numbers are hidden, making it impossible to hold the caller accountable for malicious, threatening, or abusive behaviour.

And because the caller has no identity, law enforcement is restricted as regulatory agencies may face difficulties in tracing criminal activities in that regard. Essentially such attackers  use masked or spoofed numbers to impersonate trusted entities including banks, government organizations and even businesses to carry out attacks by tricking receivers into sharing sensitive information in what is commonly referred to as social engineering attacks. Fraudsters often use call masking to execute voice phishing (vishing) schemes without being traced. The ITU recommendations to combat the broader problem of Caller ID spoofing to prevent the scourge where callers deliberately falsify their numbers are in place.

The recommendations include ITU-T E.157 which provided guidance on the delivery and format of the calling party’s number across international borders.

And to ensure origin identification, resolutions from the World Telecommunication Standardization Assembly (WTSA) encourage the delivery of international Caller Line Identification (CLI) and Origin Identification (OI) information to the destination network. The goal is to provide receiving parties and their operators with information to identify the true origin of a communication.

Aragba-Akpore is a member of THISDAY Editorial Board

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    Report: Nigeria Back on Stable Growth Path, But Pace Remains Inadequate

    Report: Nigeria Back on Stable Growth Path, But Pace Remains Inadequate

    •Says in last 15 months, real investment flows rebounded in energy, mineral resources, others

    •Urges more public sector reforms

    Ndubuisi Francis in Abuja

    Consistent with recent positive ratings of Nigeria’s economic trajectory, a new report by Quartus Economics has declared that the country is back on the path of stable growth.

    The report, however, insisted that the current level of production in the country remained too low to drive shared prosperity for all.

    The three-section report, titled, “Is Africa’s Eagle Stuck or Soaring Back to Life?” stated that perhaps the clearest sign of restored economic stability was the recovery in Nigeria’s external reserves in the middle of currency appreciation.

    It recalled that the decisive reforms of 2023–2024 (the removal of fuel and foreign exchange subsidies) were critical measures to save the economy, adding that although the immediate shocks fuelled inflation in the early months, the twin action corrected deep-seated distortions that had drained public finances and weakened market incentives for decades.

    The report said, “By 2024, the first signs of renewal began to emerge: GDP expanded by nearly four percent, manufacturing and mining sectors returned to growth, and for the first time in many years, economic expansion outpaced population growth.

    “Inflation began to ease, the naira regained modest stability, and by October 2025, foreign reserves had risen to $42 billion, signalling a slow but a genuine restoration of confidence.

    “Both foreign portfolio and foreign investments also picked up. After lean years, foreign direct investment rebounded to more than $1 billion in 2024, with fresh commitments in 2025. All of these tell a simple story: investor confidence is back on the uptick.

    “Perhaps, the clearest sign of restored economic stability is the recovery in Nigeria’s external reserves in the middle of currency appreciation.

    “For nearly a decade, Nigeria’s reserves followed a worrying downward path—falling from over $42 billion in 2018 to barely $32 billion in 2023. This decline reflected years of low oil receipts, high import bills, and heavy fiscal strain.

    “By 2023, reserves were at their lowest in seven years, a level that left both investors and policymakers anxious about the country’s external vulnerability.”

    The report added, “Then came a turnaround. In 2024, reserves climbed sharply to about $40 billion, and by October 2025, they stood at roughly $43 billion, the highest in five years.

    “This rebound is not merely a function of higher oil prices. It is underpinned by disciplined external management, growth of non-oil exports, and a notable rise in capital inflows.

    “The central bank’s more transparent market operations and a gradual shift toward market-oriented stability rather than control also helped rebuild confidence in the currency.

    “Beyond the optics, a healthier reserve position strengthens the naira, reduces speculative pressure, and allows the country to meet import

    and debt obligations without the constant fear of depletion.

    “It also signals to foreign investors that Nigeria is once again a safe destination for capital, a market where policy stability and economic fundamentals align positively.

    “The recovery of Nigeria’s reserves captures the essence of the monetary and broader economic turnaround.”

    The report stated that the foreign reserves recovery also “reflects an improvement in numbers and a return of balance. It signals a restoration of the buffers that protect the economy from shocks.

    “For a country that has weathered the trauma of currency losses and capital flight, regaining and securing this cushion is a crucial win”.

    It said, “Inflation, until recently the biggest pain point, continues to ease off. From a peak above 30 per cent, it fell to its 3-year low (around 18 per cent) by September 2025. For the first time in a decade, food inflation declined, as prices of basic items moderated.

    “The monetary policy rate, which had climbed aggressively to combat inflation, also started to decline.

    “Nigeria’s currency, the naira, has shown unusual resilience. Between December 2024 and October 2025, it gained roughly five percent against the dollar, reflecting improving balance-of-payments position and new investment flows.”

    The report, however, submitted that the effect of Nigeria’s economic descent during the 2014 to 2023 decade could not be ignored or discounted.

    According to the report, in reality, the economy emaciated, shrinking in US dollar terms by more than $200 billion during a period when the population expanded by over 40 million people. Stating that this huge deficit and the negative effect on standards of living could take decades or more to reverse, it stressed that relative to regional and aspirational peers, Nigeria retrogressed in real economic terms, pushing over 65 million residents below the poverty line.

    It further explained that despite Nigeria’s recent return to stable growth, the current level of production was too low to drive shared prosperity.

    The report stated, “Besides, today’s stock of infrastructure is low due to weak investment in the past. Thus, pushing back poverty at a quick enough pace requires more actual investment in human and physical capital than the country has the resources or capacity to deploy.

    “Beyond production to meet local demand, Nigeria’s export basket remains narrow, concentrated around crude oil and gas, a sector that offers limited capacity to drive inclusive growth except through efficient use of oil-related government revenues.

    “Current and near-term GDP growth is low Nigeria’s GDP growth rate for 2027 is forecast to be 4.4 percent. At this rate, GDP per capita by 2030 is expected to be $1,565, less than half of the value in 2014, a time when GDP stood at $574 billion, more than double today’s production, with less than 80 per cent of today’s population.

    “As a measure of living standards, the GDP per capita forecast shows that even if reforms are consolidated and growth accelerates, Nigeria’s journey to full recovery is still years away, especially in view of expansion in the country’s population.

    “While a large population is an important ingredient for rapid economic growth, a country suffers more from a rising population when it fails to make necessary investment to secure and build the productive capacity of its young population.

    “Already, when compared to other countries within and outside Africa (e.g. Ethiopia, Senegal, Indonesia, Vietnam, and Kenya), Nigeria’s productivity lags remarkably, with 5-year GDP growth merely a fraction of population growth. For peer countries, GDP grew in multiples of population growth.”

    It pointed to the persisting structural weaknesses and cultural deficiencies, noting that both threaten Nigeria’s dream of shared prosperity and diversified exports.

    According to the Quartus Economics report, reforms are still work-in-progress with much ground yet to be covered.

    It stated, “Until multiple measures of health begin to align, no recovery can be called stable. In the past year, however, Nigeria’s macro health indicators have shown respite and promise.”

    Equally, beyond progress in tax reforms, the report said fiscal management (like public-sector procurement) urgently needed change.

    It said, “Without much-needed reforms here, the transmission mechanisms for public expenditure will remain weak and fail to drive growth. The intense scramble and ‘crave’ for public office in Nigeria is merely symptomatic of a pro-establishment elite culture that seeks to feed on, rather than build the system.”

    The report also stated that 10 years from now (2035), Nigeria’s population had been projected  to surpass 280 million and peak at 320 million by 2050, adding that against a weak productive base, resources to raise, train, and expand infrastructure and social services to cater to a larger population can constrain economic growth.

    The report said Nigeria was now in a better place than it was two years ago.

    But it pointed out that the economy was like a patient, promising and vulnerable at the same time.

    It prescribed some measures, including raising production and productivity across the agriculture value chain; fostering the culture of making things; initiating crucial reforms in the public sector; and taming the “locust” culture, among others.

    On the need for public sector reform, the report stated that despite Nigeria’s largely successful privatisation programme, the three tiers of government together remained the economy’s largest spenders.

    It stated that without crucial reforms designed to direct public resources to their most effective social and economic uses, the country would continually miss both inclusive and accelerated growth.

    It said, “Reforming the public sector is not merely about cutting costs; it is about restoring purpose and efficiency to government spending.

    “Every naira deployed must translate into measurable economic and social value, not lost in layers of bureaucracy and patronage.

    “A leaner, more accountable public system would free resources for infrastructure, education, and innovation (the true drivers of growth).”

    To a fixed exchange rate that cost the economy dearly, the report said such must not happen again.

    It added, “Any promise of unearned soft life in the present only endangers the country’s future and economic fortune.

    “The real test of reform lies not in its announcement but in its endurance through political cycles.

    On the monetary side, Nigeria’s currency regime is long overdue for an overhaul.

    “The naira in the past two decades has lost so much value and gained so much weight that either introducing higher denominations or an outright redenomination is required to restore the naira’s portability.

    “Especially in the informal sector, rural areas, and open-air markets on the country-side, portability is crucial for the velocity of money. Today, the naira trades on both ATMs and POS terminals because of its weight.”

    ​  

    •Says in last 15 months, real investment flows rebounded in energy, mineral resources, others •Urges more public sector reforms Ndubuisi Francis in Abuja Consistent with recent positive ratings of Nigeria’s

    US Revokes Soyinka’s Visa, Gives No Reason for Action

    US Revokes Soyinka’s Visa, Gives No Reason for Action

    Yinka Olatunbosun and Sunday Ehigiator

    In a move that has elicited shock, the United States consulate in Lagos, yesterday, revoked the non-immigrant visa of Nigeria’s Nobel Laureate, Professor Wole Soyinka.

    The revocation, which would henceforth prevent him from entering the US, was personally confirmed by Soyinka at a media briefing at the Kongi’s Harvest Gallery, Freedom Park, Lagos.

    The decision followed a letter dated October 23, 2025 from the U.S. Consulate General in Lagos, informing Soyinka of the action.

    According to the letter, the consulate stated that his non-immigrant visa had been revoked pursuant to US Department of State regulations under 22 CFR 41.22 and was no longer valid for entry into the country.

    The letter also instructed the literary icon to submit his passport to the consulate for physical cancellation, a request he described humorously by asking if anyone in the audience could volunteer to deliver it on his behalf.

    But Soyinka said he was unaware of any wrongdoing that would justify the revocation.

    “I have no visa. I am banned, obviously, from the United States. I have no criminal record, felony, or misdemeanour that would justify this revocation. If you want to see me, you know where to find me,” he said.

    He added that he initially thought the letter was a scam but later verified its authenticity.

    At present, the exact reasons for the decision remained unclear, but many felt it might be connected to his recent criticism of the choices of the US President Donald Trump, in which he described him as Idi Amin Whiteface, likening him to the late former Uganda dictator.

    Besides, Soyinka had in December 2016, torn his green card after Trump emerged the president of the United States the first time as he was opposed to his policies on immigration.

    Although Soyinka stated that he was still reviewing his past interactions, he has yet to find anything that could have triggered the decision of the US Consulate in Lagos.

    “My relationship with US ambassadors, consuls general, and cultural attachés has always been courteous, making this development all the more puzzling,” he said.

    Asked if he would consider reapplying for a US visa, he dismissed the idea, saying he had no reason to return there.

    “How old am I? What am I going to do in the US? Human beings live there, my friends, families, colleagues. There are productions going on there.

    “I won’t take the initiative because there is nothing I am looking for there. I have contributed in establishing some institutions there. I give them as much as they gave me. They owe me nothing, I owe them nothing,” he said.

    But with a bit of humour, he added: “I have written a lot of plays about Idi Amin. Maybe it is about time I also wrote about @realDonaldTrump. Literary compliment. Maybe he would reconsider and restore my visa.”

    Soyinka maintained that he had done nothing criminal during his time in the U.S, adding that only his vocal criticism of Trump’s policies especially those targeting African nations could have prompted the visa revocation.

    The Nobel Laureate, however, added that, there was no hard feelings as a result of the development and would continue to welcome Americans to his house in Abeokuta, Ogun State, as he has no issues with the people or the nation.

    According to him, as a global citizen, he would continue to speak against racism and what he felt wrong with policies of governments, including that of Donald Trump.

    “I will continue to welcome any American to my home if they have anything legitimate to do with me,” Soyinka maintained.

    ​  

    Yinka Olatunbosun and Sunday Ehigiator In a move that has elicited shock, the United States consulate in Lagos, yesterday, revoked the non-immigrant visa of Nigeria’s Nobel Laureate, Professor Wole Soyinka.

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