Aggregation of VoIP streams in a 3G mobile network: a teletraffic perspective

The ubiquity and convergence of mobile telephony and the Internet leads many to believe that future isochronous telephony data will be transported in the form of voice-over-IP (VoIP) datagrams. This paper investigates the modelling and aggregation of multiple VoIP streams. The relationship between the number of VoIP sources, output link rate and certain teletraffic metrics is investigated. Thereafter, an exemplar network consisting of a small cluster of wireless cells is considered and a number of different handover strategies enacted. The frequency and duration of handovers are varied to investigate the effects on system performance when VoIP calls are ongoing. The findings in this paper could be extremely useful when dimensioning networks as they provide insight into the QoS obtainable for the individual streams. This is a critical issue for real-time applications such as VoIP.