An Analytical study to Calibrate Quality of Service and Security Parameters of Voice Transmission over IPSec (QSVoIP) for Maximum Number of Calls with Acceptable Voice Quality

Abstract

Security in Voice-over-IP (VoIP) concerns protecting both the content, by encryption, and speaker identification, by authentication. IP Security (IPSec) technique can be used for this purpose. In addition, IPSec is usually applied with Encapsulating Security Payload (ESP) using tunnelling protocol. However, security strengthen of Voice-over-IPSec (VoIPSec) may affect Quality of Service (QoS) during VoIP transmission. This paper conducts approach called QSVoIP that calibrates QoS and Security parameters of Voice transmission over IPSec for maximum number of calls with maintaining acceptable voice quality that can be heard clearly by the listener. QSVoIP tries to reduce human threat in many aspects, such as packet sniffers, middle attacks, and several types of voice traffic analysis. QSVoIP conducts a developed method that estimates number of voice calls that can be applied in IPSec network with subject to maintain acceptable voice quality. This paper also presents performance analysis of VoIP communication over IPSec network, which has been executed for different scenarios using OPNET simulator in terms of end-to-end delay, jitter, and packet loss. The simulation results’ analysis shows that transmitting voice over IPSec dramatically deteriorates the quality of VoIP. Results have shown that QSVoIP approach can effectively help network administrators and designers to determine the number of voice calls that can applied for a particular network with acceptable voice quality.