Backplane bandwidth, also referred to as switching capacity, is the maximum data throughput between a switch's interface processor and data bus. Imagine it as the total number of lanes on an overpass—more lanes mean more traffic can flow smoothly. I thought switching capacity and backplane capacity are same, but it seems they arent. Since the communication between all ports needs to be completed through the. S16700 series switches consist of two models with four Line Processing Unit (LPU) slots and eight LPU slots respectively. Given that all port communications pass through the.