Evaluation of quality in encrypted VoIP calls

The purpose of this work is to evaluate the quality of encrypted VoIP calls with different encryption algorithms through OpenVPN software, in order to identify differences in results between encryption algorithms and also differences between non-encrypted and encrypted calls. This evaluation will take into account the MOS (Mean Opinion Score), a method to indicate user satisfaction of voice communication quality. The encrypted VoIP calls will occur in different network scenarios that present different network bandwidths and different problems, like packet loss, out-of-order packets, and delay.