On securing real-time speech transmission over the Internet: An experimental study

We analyze and compare several soft real-time applications designed for the secure transmission of packetized audio over the Internet. The main metrics we consider for the purposes of our analysis are (i) the computational load due to the coding/decoding phases, and (ii) the computational overhead of the encryption/decryption activities, carried out by the audio tools of interest. The main result we present is that an appropriate degree of security may be guaranteed to real-time audio communications at a negligible computational cost if the adopted security strategies are integrated together with the playout control mechanism incorporated in the audio tools.