Karsten Lereuth is the chairman and co-founder of Telebix, a member of the telco business community leading the roll-out of AB Handshake, the global initiative to stop caller ID spoofing and prevent fraud in all telecom networks. Karsten has been an industry leader for over three decades, routinely rubbing shoulders with the decision-makers who shape the telecom industry. He has been involved in almost every aspect of telecom, launching a mobile network, managing wholesale services for multinational groups, overseeing sales for an ISP, running an IT consulting business, and spending four years as the general manager of BT in Germany and Austria.

Although voice traffic has been on the decline for many years due to the adoption of over-the-top services, it remains the preferred method of communication for millions of global users. Now, during the coronavirus pandemic, when travel isn’t possible, the ability to call business partners, friends and family members is more critical than ever. Unfortunately, it is also a top fraud risk. “The AB Handshake call validation technology literally turns the whole paradigm of fraud management activities upside-down.” Karsten says, explaining why he brought Telebix into the community. “An operator’s fraud management function is normally perceived as reactive, more concerned with analysis of what has already happened than with prevention. With the AB Handshake, telcos are empowered to prevent any kind of fraud traffic in real time.”

Traditional fraud management systems give some fraudulent traffic a pass, as they do not verify each and every call. Instead, they utilize sampling and probability models, often based on CDR (Call Detail Record) analysis or expensive database queries. Since the analysis takes place after the fact, there is no real prevention—the data gathered is used primarily to improve the anti-fraud rules of the company’s internal system and stay one step ahead of the scammers. Unfortunately, the fraudsters also learn quickly, and find ways to get around new protections. Every company is left to develop its own solution and look after its own interests—there is no knowledge sharing, and no incentive for companies to cooperate.

AB Handshake has changed the paradigm with the understanding that effective fraud prevention must be a community endeavor. Rather than using probability models, AB Handshake validates each and every call, and stops the call in real time if it isn’t verified by both the originating and terminating network. It gives telcos a clear incentive to cooperate—the system is only effective when it is implemented on both sides. The AB Handshake solution can tackle almost all types of fraud– interconnect bypass, CLI spoofing, robocalls, wangiri, short-stopping, call-stretching, PBX hacking, and more, bringing value to operators no matter where they are and what threats they face. Since AB Handshake validates each call rather than working with sampling or probability models, no fraudulent traffic gets through—it’s 100% effective.

Until every telco has joined the AB Handshake community, spoofing and fraud will not disappear entirely. However, Karsten believes that wholesale carriers and retail operators who have joined the community will prefer to work with one another, so as not to exchange traffic with operators whose traffic cannot be verified. As more operators join the community, he believes that the adoption of the AB Handshake solution will become an entry ticket for interconnection with big operators and groups.

“I would say it is all about fair play,” he concludes. “If you are willing to join the clean game, there is no reason to refuse the tools that can prove your transparency. The AB Handshake provides the opportunity to establish a virtual direct interconnect with all the partners, even the ones that you do not know. It creates a community of trusted partners, and I can see absolutely no reasons not to join it.”