The structure of the Ethernet switch is that each port is directly connected to the host, and generally work in full-duplex mode. The switch can connect many pairs of ports at the same time so that each pair of communicating hosts can transmit data without conflict as if it were an exclusive communication medium.
1. The role of the Ethernet switch
Ethernet switch applications are the most common, the price is cheaper. Full range of grades. Therefore, the application area is very wide, in large and small local area network can see their trace. Ethernet switches typically have several to several dozen ports. In essence, is a multi-port bridge. In addition, its port rate can be different, the work can also be different, such as can provide 10M, 100M bandwidth, providing half-duplex, full-duplex, adaptive work and so on.
2. How the Ethernet switch works
The Ethernet switch is the data link layer of the machine, Ethernet uses the physical address (MAC address), 48 bits, and 6 bytes. It works as follows: When a broadcast frame is received, it forwards to all ports except the receiving port. When a unicast frame is received, it checks its destination address and corresponds to its own MAC address table. If there is a destination address, it is forwarded. If there is no flooding (broadcast), if there is no host MAC address and frame If the destination MAC address is the same, the host MAC address is automatically added to its MAC address table.
The switch splits the collision domain, and each port is independent of a collision domain. Each port, if there is a large amount of data to send, the port will first receive the waiting to send the data stored in the register, when sent to send again.