Although routers and switches are both network devices, they have some differences in functions and application scenarios and cannot completely replace each other.
Routers are mainly used to connect different networks to achieve communication and data transmission between networks. It can route data packets to the correct destination network based on network addresses (e.g., IP addresses). The router also provides features such as network isolation, security, and access control.
Switches are mainly used to connect multiple devices in the same network to provide high-speed data exchange between devices. It performs data frames based on MAC addresses to enable communication between devices within the LAN.
In some simple network environments, switches may be sufficient for basic connectivity needs, but routers are indispensable when complex network topologies or when communication needs to be carried across different networks. Of course, in some cases, a Layer 3 switch can be used as a router, such as network segment isolation, DHCP, more precise port definitions, and so on.
For example, in a corporate network, routers are often used to connect different subnets or WANs (wide area networks) to enable communication between different locations. In large LANs, switches can provide more efficient connectivity to internal devices.
As a result, routers and switches play different roles in the network, and their functions complement each other, rather than replace each other. Depending on your network requirements and topology, you may need to use both routers and switches to build a complete and efficient network infrastructure.