AbstractudIn this study, a first order investigation of the issue of resource allocation betweenudcircuit voice, packet data and packet voice was completed. The study was done withudreference to the GSM / GPRS air interface. To study the allocation of resources,udsuitable traffic source models were developed to represent the nature of the trafficudoffered to the base station subsystem. Circuit voice and packet data were representedudusing Markovian arrivals and exponentially distributed holding times. Voice over IPudwas modelled using a two-state Markov modulated Poisson process. The base stationudsubsystem was modelled as a continuous time controller with eight channels (oneudGSM / GPRS TDMA frame). The radio propagation environment was consideredudby means of a large-scale propagation model, which would merely alter the loadudpresented to the developed simulator package. From the results of the simulations,udit was found that insufficient data resources lead to similar packet delay regardlessudof the packet size. It was found that if capacity on demand is used, then the dataudresources could equal the load. In the case of sufficient data channels, with capacityudon demand, additional channels have a greater effect on average delay than theudprobability of it occurring. Prioritisation of VoIP packets did not significantly alterudthe probability of delay but affected the average packet delay. Packet size had audgreater effect on average delay than the probability of delay. In the case of all eightudchannels being used for VoIP and data, the combined load should not exceed sevenuderlang, indicating that a higher voice load could be supported with VoIP than withudcircuit switched voice.
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