使用snmp协议环境并且进行以太网络的拓扑发现,Snmp agreement to use the Ethernet topology discovery

实现局域网拓扑发现，可以发现路由器，交换机，但是基于snmp，要求路由器必须支持此协议-LAN topology discovery can be found in routers, switches, but based on the snmp, request router must support this protocol