1997年底美国 Cisco 系统公司推出了四种适用于 Cisco 7500和7200系列路由器的高性能集成接口。这种新的“E3/T3上包传输(Packet-Over-E3/T3)”——POET 接口在增加网络管理性和减少机柜空间需求的同时,使服务供应商和企业客户能够增加大量的租用线路连接。通过把 DSU 集成到路由器中,POET 接口支持 At the end of 1997, Cisco Systems of the United States introduced four high-performance integrated interfaces for Cisco 7500 and 7200 series routers. This new “E3 / T3 Packet-Over-E3 / T3” - POET interface enables service providers and enterprise customers to add significant leases while increasing network management and reducing cabinet space requirements Line connection. The POET interface is supported by integrating the DSU into the router