Performance of 3-level scheduling in optical core switch for Data Center interconnection

In this paper a 3-level quality of service (QoS) scheduling is applied to a reference Data Center (DC) optical core switch with wavelength conversion and queueing capability. The scheduling approach is able to manage guaranteed traffic and statistical multiplexed traffic, this last further divided in pure loss traffic and delay tolerant traffic. With respect to previous works mainly focused on aggregation of differentiated traffic on output interfaces and unlimited wavelength conversion capability, a switch which exploit contention resolution in time and wavelength domain for statistical multiplexed traffic is here considered and the limiting effect of contention on scheduling is evaluated. Results obtained by an ad hoc simulator outline show the effect of traffic mix and switch architecture on forwarded traffic. The numerical evaluation are discussed in support of DC core switch design procedure.