In this paper, we present a performance analysis of the slotted ring protocol for a voice/data integrated network environment. At each node we assume two types of packet generation, data and voice, and construct our model to provide dedicated buffers for storing each type of packet. Packet transmission is performed according to the slotted ring protocol with priority given to the voice packets. In particular, we defined an on-off model reflecting real behavior for the generation of voice packets and assumed finite capacities for the packet buffers to allow for the calculation of buffer overflow probabilities. In communication systems which handle voice packets, receiving nodes are normally equipped with buffers for accommodating the delays in packet transmission to prevent degradation of audio quality, although excessive delays can cause packets to expire and be discarded.
In this paper, we provide for the analysis of the rate at which voice packets are discarded at such nodes and discuss in detail the performance of voice packet transmission. The analysis of our model is based on the method of the equilibrium point analysis and we verify the accuracy of our results by comparing them with the results of simulation. Furthermore, as an example of an application of our findings, we examine the effects of changing slot lengths on the performance of a network.