Two approaches are available, one is to lift the switch capacity of the single-stage switch, but this alternative is always unsuccessful for the practical implementation limits of the single-stage switch.

• 解决可扩展性有两种基本途经:一种是提升单级交换单元的交换容量,但是由于工程实现的限制,单级交换单元的交换容量不可能很大;