A Dynamic Frame Sizing Algorithm for CICQ Switches with 100% Throughput

A Combined Input and Crosspoint Queueing (CICQ) switch is a switch that has both buffers at the crosspoints of the switch fabric and buffers at the inputs. Inspired by the fixed frame based algorithm for an input-buffered switch and the smooth scheduling algorithm for a CICQ switch, in this paper we propose using a dynamic frame sizing algorithm for a CICQ switch. It is formally shown that such a CICQ switch indeed achieves 100% throughput for certain Poisson-like traffic models. This is done without using the framed Birkhoff-von Neumann decomposition needed. Moreover, such a CICQ switch only requires a two-cell buffer at each crosspoint when there is only unicast traffic. Unlike input-buffered switches, the dynamic frame sizing algorithm also achieves 100% throughput in the setting of multicast traffic. This is done at the cost of increasing the buffer size at each crosspoint.