In today's society,the Internet has penetrated into all aspects of our lives, of which the wired network and wireless networks are the most familiar. At present the most famous cable network is Ethernet. But with the development of techno oav. wireless networks are aoina deep into our lives WLAN is a promising development field.Although it may not completely replace Ethernet, it is gaining more and more users.The most promising wireless network is Wifi.The following describes the comparison between the two.

    Today, the wireless network is the most widely used, most frequently usedand most convenient network. Howevercompared with the wired network,the wireless network still has many disadvantages:

1) The communication parties need to establish a connection before communication because they communicate via wireless:the wired network is directly connected with cables, without this process.

2) Both parties communication mode is half-duplex; wired networks can be full duplex

3) The probability of error under the network laver during communication is very high so the retransmission probabillity of the frame is very high You need to add a retransmission mechanism to the protocol under the network layer (you can't rely only on the overhead of the above TCP/IP such as delay waiting for retransmission). Howeverthe error probability of a wired network is very small so there is no need to have such a complex mechanism in the network later.

4) Data is carried out in a wireless environmentso packet capture is very easy and there are security risks.

5) Because of the power consumption of receiving and transmitting wireless signals the power consumption is high, which is a test for the battery.

6)Compared with wired networks, the throuahput is low. which is aradualy improvina.The 802.11r protocol can achieve a throughput of 600Mbps.