Analysis of multi-homed SCTP and delay-centric transmission for VoIP traffic in lossy networks

Nowadays a number of Internet access possibilities can be simultaneously available to fixed or mobile users. Adequate selection of the most appropriate communication path can improve transmission quality for Voice over IP (VoIP) applications by providing smaller delay and smaller packet loss. Stream Control Transmission Protocol (SCTP) is currently being studied as a good alternative for implementing this type of control due to its multi-homing capability. Different parameter configurations can affect performance of path selection mechanisms. In this paper the performance of delay-centric path selection method and SCTP standard mechanism to deal with path failure are analyzed. Communication performance of VoIP transmission is evaluated by comparing the session Mean Opinion Score (MOS) that is calculated using E-model from ITU-T. Simulated scenarios include packet losses and different levels of average delay on the available paths. Results show that delay-centric method combined with standard failure detection mechanism with nondefault parameters performs well for most common cases.