Optical Packet Switching (OPS) is a technology which thanks to its speed of operation may become popular in next-generation networks. Because optical packets are not buffered it is necessary to develop new mechanisms which would allow quality of service management in OPS networks. The paper discusses the architecture of OPS networks of the ring type with nodes enabling optical packet switching, equipped with the mechanism of Quality of Service (QoS) management. The differentiation of the quality of service was achieved by means of the proposed mechanism of priority registers with the timeout mechanism. This enables the network to be used for transporting various classes of data with varying requirements as to the quality of service. Simulation trials have been conducted and an analytical model for this type of network has been proposed.