quagga 源代码，用于在linux上和zebra配合把pc虚拟成以太路由器，方便搭建环境。-quagga source code for linux and zebra on the pc into a virtual tie Ethernet router, easy to set up the environment.

深入理解虚拟局域网（VLAN）的作用，并体会VLAN与子网之间关系 路由器的工作原理及其作用，认识路由器的各种接口-Deep understanding of the role of virtual local area network (VLAN), and understand the relationship between VLAN and subnet The working principle of router and its role in understanding t