Modeling and optimization of a special multistage star switching (SMSSS) system with SEs at unequal port rates

There has been lack of an efficient design and evaluation method for the multistage star switching (MSSS) architecture in which the ports' rates of each switching element (SE) are unequal. Thus, we identify and propose a special MSSS (SMSSS) model for the first time, where all special SEs, known as basic switching modules (BSMs), are connected hierarchically into a tree profile. Unlike the existing investigations, each BSM in this model is characterized by one high-rate port and several low-rate ports. This study focuses on the analysis, design and optimization of the SMSSS model. Moreover, we propose a novel BSM cost model which relates to its flux factor considered rarely in existing studies. Two examples are demonstrated to obtain the optimal structure parameters of the SMSSS system with a minimum overall cost. The comparison of the proposed SMSSS with similar fat tree structures indicates its relative advantages.