1, the Ethernet Tester works in the second layer of the OSI (data link layer), so the working principle of the switch is relatively simple, and the router works in the third layer (network layer) of the OSI, which can get more protocol information, the router can Make smarter forwarding decisions.
2. The switch uses the physical address or MAC address to determine the destination address for forwarding data, and the router uses the ID number (ie, IP address) of the different network to determine the address for data forwarding. The MAC address is usually provided by the hardware, distributed by the network card manufacturer, and has been solidified into the network card, which is generally unchangeable, and the IP address is usually automatically assigned by the network administrator or the system.
3. The network segment connected by the Cheap Network Tester still belongs to the same broadcast domain. Broadcast packets will be transmitted on all network segments connected to the switch. In some cases, communication congestion and security holes may occur. Although the switch above the third layer has the VLAN function, the broadcast domain can also be divided, but the sub-broadcast domains cannot communicate with each other, and communication between them still requires a router.
4. The router only forwards the data packets of a specific address, and does not transmit the data packet transmission that does not support the routing protocol and the transmission of the unknown target network data packet, thereby preventing the broadcast storm.
In comparison, the function of the router is stronger than that of the switch, but the speed is relatively slow and expensive. The Layer 3 switch has the ability to forward packets at the line speed and has good control functions of the router, so it can be widely used.