(What kind of network do small LANs need? Usually, most of their network building needs still rest on the ability to access the Internet, share office equipment resources, share file resources, and run OA (office automation) software to work together; Only a small number of business processes are ported to the Internet to run (this requires the ability to develop their own web background programs). But there are also some computers with sensitive data (such as finance, contract scheme documents, and development strategic plans). These companies refuse to connect them to the network and prefer these computers to become an information island. One reason is that the cost of safety is too high for enterprises to bear; One reason is distrust of security measures.? The configuration inside is quite old, but I hope it can give you an idea,)