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科技发展一日千里,尤其是网络技术更是日新月异。“三层交换”(Layer 3 Switching)在短时间内的迅猛发展就是很好的例证。 今天,一个能保证三层交换的交换器已成为网络的主流,路由器却被摆到了网络的“边缘”上。除非有广域网的需求,一般不用比交换器速度慢、价格高的路由器。但由于某种原因,如便于管理、有效控制广播或要集成不同的网(如FDDI和10Base-T的互连)等,有的网里可能需要允许不同的“子网”(Subnet)或不同的IPX网共存,如果这些局域网间又需要通讯,此时路由器便十分有效了。 路由和交换之间的区别在于:路由是网络七层参考结构的第三层功能,交换则是第二层。拿以太网为例,如果所有节点都是通过集线器互连的话,集线器逻辑上和中继器一样,都是第一层设备,它们在任何一个端口上收到的东西都会不加区分地传出来。交换器则会在操作中不断地收集资料去建立一个地址表,记录每个MAC地址来自哪一个端口,因此在收
The rapid development of science and technology, especially network technology is changing with each passing day. The rapid development of “Layer 3 Switching” in a short period of time is a good example. Today, a switch that guarantees Layer 3 switching has become the mainstream of the network, but routers are placed on the “edge” of the network. Unless there is a WAN demand, generally not slower than the switch, the high price of the router. However, for some reason, such as being easy to manage, controlling broadcasting effectively or integrating different networks (such as FDDI and 10Base-T interconnection), some networks may need to allow different “subnets” or different IPX network coexist, if these LANs need to communicate again, then the router will be very effective. The difference between routing and switching is that routing is the third layer of the network’s seven-layer reference structure, and the second layer is the exchange. Taking Ethernet as an example, if all the nodes are interconnected through hubs, the hubs are logically the same as the repeaters and are the first tier of devices, and they receive anything on any one port without distinction . The switch will continue to collect data in the operation to establish an address table, record each MAC address from which port, so the income