Batched circuit switched routing for efficient service of requests

Circuit switching protocols were largely developed in light of ATM virtual circuits and also for the case of all-optical networks. The merging of ATM and IP packet switching technology may banish true circuit switching in the digital domain due to fast switching networks using TDM. Even so, the characteristics of all-optical light paths (an optical circuit switched path) are so desirable that digital WANs using ATM may eventually be completely augmented by optical WANs using a hybrid optoelectronic or complete optical switching fabric. A fundamental problem is servicing a large number of requests while maintaining a low blocking probability where a request is blocked if the path it requires is in use by a circuit. We present a simple routing method, namely batched circuit switching (BCS), that batches requests according to the rate of arrival and service time. Compared to orthodox circuit switching (CS), BCS provides superior request service times due to the observation that many requests may traverse the same circuit (or channel) during the batch time interval, rather than being blocked by preceding requests (as is the case for CS). Thus, BCS exhibits better utilization of the network resources than CS. We demonstrate the requirements for this system to be stable, namely that the batch size must not increase to infinity before being serviced and the relationship between λ (the arrival rate of requests) and μ (the service rate of requests) to ensure stability