New authentication applications in the protection of caller ID and banknote

In the era of computers and the Internet, where almost everything is interconnected, authentication plays a crucial role in safeguarding online and offline data. As authentication systems face continuous testing from advanced attacking techniques and tools, the need for evolving authentication technology becomes imperative. In this thesis, we study attacks on authentication systems and propose countermeasures. Considering various nominated techniques, the thesis is divided into two parts. The first part introduces caller ID verification (CIV) protocol to address caller ID spoofing in telecommunication systems. This kind of attack usually follows fraud, which not only inflicts financial losses on victims but also reduces public trust in the telephone system. We propose CIV to authenticate the caller ID based on a challenge-response process. We show that spoofing can be leveraged, in conjunction with dual tone multi-frequency (DTMF), to efficiently implement the challenge-response process, i.e., using spoofing to fight against spoofing. We conduct extensive experiments showing that our solution can work reliably across the legacy and new telephony systems, including landline, cellular and Internet protocol (IP) network, without the cooperation of telecom providers. In the second part, we present polymer substrate fingerprinting (PSF) as a method to combat counterfeiting of banknotes in the financial area. Our technique is built on the observation that the opacity coating leaves uneven thickness in the polymer substrate, resulting in random translucent patterns when a polymer banknote is back-lit by a light source. With extensive experiments, we show that our method can reliably authenticate banknotes and is robust against rough daily handling of banknotes. Furthermore, we show that the extracted fingerprints are extremely scalable to identify every polymer note circulated globally. Our method ensures that even when counterfeiters have procured the same printing equipment and ink as used by a legitimate government, counterfeiting banknotes remains infeasible