The expansion of devices and technologies for Internet of Things (IoT) applications brings with its great challenges to ensure secure communications. Traditional cryptographic systems cannot be applied directly on constricted devices. Physical layer security mechanisms attract increasing attention, which could be implemented in parallel with higher layer methods. FTN (faster-than-Nyquist) signaling is a promising technology to improve transmission speed without increasing bandwidth, but introduce inter-symbol interference (ISI). FTN signaling can be used as a form of artificial noise to achieve security in the physical layer. The ISI that is introduced due to FTN signaling can be reversed to some degree by the receiver, but cannot be completely removed, causing a degradation in the bit error ratio (BER). In this paper we propose to adjust the value of the roll-off factor of the pulse shaping filter in each symbol, exploiting the gain in terms of spectral efficiency caused by the FTN signal in order to improve performance in terms of BER. The results show that the proposed scheme can significantly improves the performance in terms of BER. Guaranteeing, in coexistence with other security mechanisms and despite the presence of potential eavesdroppers, a reliable and secure flow of information on DVB-S2 scenarios.