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Ofcom wants networks to block scammers

Written by Rachael Brown | Oct 27, 2021
 
 
Almost 45 million consumers were targeted by phone scams this summer. And Ofcom is asking phone networks in response to do more.
 
Ofcom wants networks to start blocking calls that use internet-based calling technology to make a phone call or text look like it's coming from a real UK telephone number. 
 
This is critical because the vast majority of scam calls originate in a country other than the country of the target.
 
In fact, Pindrop Labs found that 64% of fraud calls come from abroad. By comparison, only 6.6% of legitimate calls are international. This means attackers call across international borders at 10x the rate of legitimate callers.
 
Internet-based calling technology is used by millions of consumers and businesses globally to make phone calls free or cheaply every year. This technology is used by Skype, Zoom, Microsoft Teams and WhatsApp. 
 
Despite this, many telecoms companies do not currently inspect the traffic they receive via this technology, simply letting it through onto the network. These efforts by Ofcom would change this. 
 
Gabriel Cirlig of US cyber-security firm Human commented that "Because of this lower barrier of entry, it is very easy for scammers to build their own systems to spoof mobile numbers" he went on to say that "the cybercriminals are essentially pretending to be legitimate corporate telephone networks in order to have access to legitimate telco infrastructure."
 
These scammers utilise modern spoofing tools, which are simple to use, widely available and often free to disguise their phone numbers and thus get through to potential victims. They do this by changing the ANI, which makes international calls appear on Caller ID as local calls from legitimate customers.
 
While blocking this traffic will definitely be effective in reducing the volume of scam calls, it may not entirely solve the problem.
 
Much of the UK still relies on old copper-based networks dating back to the 1970s, and while this is changing as they are being fazed out in favour of the fibre network, this present-day reality means these scams will continue.
 
Experts agree that the only way to completely fix the problem is to implement new telephone identification protocols that enable phone networks to authenticate that all calls and text messages actually come a real telephone number.
 
And of course, phone users should also follow advice on how to keep themselves safe from organisations like Ofcom. You can also watch and learn from videos, like this one of this conman in action, of signs you may be being scammed. 
 
Photo by Masaaki Komori on Unsplash