Switched LAN can provide users with shared LAN can not achieve some of the features, including the following aspects:

(1) Isolation of the conflict domain In the shared Ethernet, the use of CSMA / CD algorithm for media access control. If two or more sites simultaneously detect that the channel is idle and the frame is ready to be sent, they will conflict. A group of competing channel accesses a site called a collision domain. Obviously the same competing domain in the conflict domain will lead to conflict and avoidance. And sites with different conflict domains do not compete for public channels, and they do not conflict. In the switched LAN, each switch port corresponds to a collision domain, the port is the end of the conflict domain, because the switch has a switching function, different ports between the site will not conflict. If each port is connected to only one computer site, there is no conflict between any pair of sites. If a port is connected to a shared LAN, there is a conflict between all the ports of the port, but there will be no conflicts between the port's site and the other ports of the switch. As a result, the switch isolates the conflicting domains of each port.

(2) Extended distance The switch can extend the LAN distance. Each switch port can be connected to a different LAN, so each port can reach the maximum distance required by different LAN technologies, regardless of the length of the LAN that connects to other switch ports.

(3) increase the total capacity in the shared LAN, its capacity is shared by all access devices. In a switched LAN, the total capacity of the switched LAN increases as the number of ports of the switch increases due to the dedicated capacity of each port of the switch. So the number of data provided by the switch is much larger than that of the shared LAN.

(4) Data rate flexibility For shared LANs, different LANs use different data rates, but all devices connected to the same shared LAN must use the same data rate. For switched LANs, each port of the switch can use a different data rate, so you can deploy the site at a different data rate, very flexible.