对光分组交换中节点共享(SPN)的结构进行了理论分析,推导出SPN系统的丢包率公式,并对系统丢包率与负载、输入光纤端口数和每纤波长数的关系进行了数值计算。结果表明:当共享波长转换器的数目从0开始增加时,首先改善的是低负载的丢包率,当低负载的丢包率接近极限后,开始明显改善中负载的丢包率,最后改善高负载的丢包率。 The structure of node sharing (SPN) in optical packet switching is analyzed theoretically, and the formula of packet loss rate of SPN system is deduced. The relationship between the system packet loss rate and the load, the number of input optical fiber ports and the number of each fiber is numerically Calculate. The results show that when the number of shared wavelength converters increases from 0, the first is to improve the low-rate packet loss rate. When the low-rate packet loss rate approaches the limit, the packet loss rate at medium load starts to improve and finally improves High load loss rate.