For the full utilization of the high transmission bandwidth of optical fiber, several optically transparent switching nodes are proposed for use in photonic LANs, MANs or B-ISDN access networks. The node design is simple and adaptable to various networks including rings, buses, and WDM networks. In this paper, we analyze the performance of the optical ring networks which utilize the photonic packet switching nodes. A quantitative performance comparison study is carried out to observe the effect of header speed on the optical ring network performance.

Much has been previously written about the performance of slotted ring networks. However, the results are not appropriate to apply for the new generation slotted rings, like counter-rotating multichannel slotted rings. In this paper, a novel technique for quantitative measurement of average transfer delay of a class of slotted rings is presented. The approach is expanded to compare the average transfer delay of various slotted rings including counter-rotating multichannel slotted ring networks. An extensive simulation study has been carried out to verify the derived analytical results. The analytical results show an excellent agreement with simulation results over a broad range of parameters. The average transfer delay of the counter-rotating slotted ring network is about half that of the conventional multichannel slotted rings. Spatial reuse using the counter-rotating channel configuration also increases the effective ring throughput significantly, compared to conventional simple multichannel ring networks. The results show that the major part of the cell transfer delay comes from the propagation delay from a source to a destination. It is also observed that the network throughput depends upon the aggregated transmission capacity of the network.

The authors introduce a communication subnet architecture, called Hybrid Meshnet, for local area networks (LANs) that is designed to achieve a high degree of network performance and flexibility. These objectives are achieved by utilizing a dual-channel structure. A token ring is used for short or prioritized data transmissions. A complementary mesh network with arbitrary data links is used for relatively high volume and low-priority data transmission. A distributed network control and routing mechanism allocates the communication network nodes. Hybrid Meshnet supports a LAN system in which the communication structure may easily be modified and changed by the insertion or deletion of data links.>

This paper presents a hybrid architecture for local area networks (LANs) which combines the advantages of token ring and mesh networks while remaining relatively simple. Each node may have two communication channels. The first is a token ring and is used for short or prioritized message data transmissions. The other consists of an arbitrary collection of data links, which are used for relatively high volume and low priority data messages. With this architecture, a LAN can be installed in the form of token ring and can be upgraded and “tuned” to its application environment by the insertion of node-to-node data links.