Channel and Receiver Contention in Optical Flow Switching Networks

An increasing number of users perform large transfers over data networks. While, for the most part, these transfers are currently performed over the IP network, a number of studies advocate the use of end-to-end optical circuits to support these resource-consuming jobs. One of the major advantages is the ability to carry a large fraction of the overall network traffic using the relatively lower-cost and lower-power optical equipment, when compared to IP routers. For example, in optical flow network, end-to-end optical circuits can be established by reserving wavelength channels only when needed. Once the circuit is established, the large data set is seamlessly transferred across the network without requiring IP routers to be involved in the data transfer. For a circuit to be successfully established the following conditions must be simultaneously met: a transmitter must be available at the sender, a receiver must be available at the destination, and a wavelength channel must be available across the network to connect the sender to the destination. Data transfer can start only when the conditions above are simultaneously met. As a result, a request can experience a delay before being established. Network throughput and delay are affected by the availability of network channels (channel-contention) and end-user's receiver (receiver-contention). The contribution of this paper is twofold. First, channel throughput and delay are analytically estimated. Second, the analytical results are validated using simulation results. A number of experiments are conducted using the presented analytical models and simulation platform to investigate the effect of channel and receiver contention on throughput and delay.